From jimray at hartcom.net Wed May 4 13:25:37 2022 From: jimray at hartcom.net (jimray at hartcom.net) Date: Wed, 4 May 2022 15:25:37 -0400 Subject: [Mgs] Coughing, spitting, and dying In-Reply-To: <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> Message-ID: To all of you who responded to my cry for help, THANK YOU so much for your suggestions. As it turns out, the root cause of the problem was timing. The stock distributor had been upgraded several years ago to a Pertronix electronic module which had worked itself loose inside the distributor causing the timing to become erratic. Tugging on the leads to the coil would cause the engine to increase its RPMs and run smoothly. Pushing them back into the distributor reintroduced the backfire and coughing. Thanks again for everyone?s help. Jim From: Mgs On Behalf Of John DiFede Sent: Sunday, April 24, 2022 7:28 AM To: Robert Rutherford Cc: MGB-V8 at autox.team.net; MG Digest Subject: Re: [Mgs] Coughing, spitting, and dying Sounds like a fuel problem. The Edelbrock 1404 is a simple carburetor to work on as it is a copy of the Carter AFB carb used since the 60?s. Is your choke set properly when cold and hot? The AFB used a mechanical fuel pump- make sure that facet pump you?re using has the correct fuel pressure for the AFB. Also check your vacuum. Is the vacuum reading steady or is the gauge needle fluctuating back and forth? You may have a vacuum leak affecting fuel mixture. When the engine is cold and the choke is on you have a rich mixture allowing the engine to run poorly. Once the choke opens the mixture goes lean due to the vacuum leak possibly leading to your motor stalling. Sent from my iPhone On Apr 23, 2022, at 11:10 PM, Robert Rutherford > wrote: ? Coughs, spits, dies - sounds like Covid to me. On Apr 21, 2022, at 12:34 PM, Max Heim > wrote: [?EXTERNAL] Sounds more like a carb/fuel issue to me. Can?t see how it would be electrical. Sent from my iPad On Apr 21, 2022, at 11:58 AM, jimray at hartcom.net wrote: ? Have an 80 MGB V8 conversion that has developed a problem I can?t get my hands around. When cold it coughs and sputters when first starting up and when warm will not run at idle without stalling after several minutes. Thinking it might be an electrical issue, I replaced the plugs, plug wires, distributor cap, coil, and battery. It has a PerTronix Ignitor module installed which I did not replace. The battery shows 12.7 volts on my meter. The alternator is producing 14.6 volts at ~1500 RPMs and 14.3 under load. Fuel is fed to an Edelbrock 1404 carburetor via a Facet electric pump with new filters in the line at the pump and just before the carburetor. I use 93 octane non-ethanol gas. I appreciate any thoughts or suggestions you may have. Jim Ray _______________________________________________ Mgs at autox.team.net Donate: http://www.team.net/donate.html Suggested annual donation $12.75 Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive Unsubscribe: http://autox.team.net/mailman/options/mgs/mvheim at sonic.net _______________________________________________ Mgs at autox.team.net Donate: http://www.team.net/donate.html Suggested annual donation $12.75 Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive Unsubscribe: http://autox.team.net/mailman/options/mgs/rrutherf at ucalgary.ca _______________________________________________ Mgs at autox.team.net Donate: http://www.team.net/donate.html Suggested annual donation $12.75 Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive Unsubscribe: http://autox.team.net/mailman/options/mgs/difejo1 at gmail.com -------------- next part -------------- An HTML attachment was scrubbed... URL: From h.duinhoven at planet.nl Sat May 7 23:50:18 2022 From: h.duinhoven at planet.nl (h.duinhoven at planet.nl) Date: Sun, 8 May 2022 07:50:18 +0200 Subject: [Mgs] Coughing, spitting, and dying In-Reply-To: References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> Message-ID: <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> Always good to learn of someone?s experiences? Hans Van: Mgs Namens jimray at hartcom.net Verzonden: Wednesday, 4 May 2022 21:26 Aan: 'John DiFede' ; 'Robert Rutherford' CC: MGB-V8 at autox.team.net; 'MG Digest' Onderwerp: Re: [Mgs] Coughing, spitting, and dying To all of you who responded to my cry for help, THANK YOU so much for your suggestions. As it turns out, the root cause of the problem was timing. The stock distributor had been upgraded several years ago to a Pertronix electronic module which had worked itself loose inside the distributor causing the timing to become erratic. Tugging on the leads to the coil would cause the engine to increase its RPMs and run smoothly. Pushing them back into the distributor reintroduced the backfire and coughing. Thanks again for everyone?s help. Jim From: Mgs > On Behalf Of John DiFede Sent: Sunday, April 24, 2022 7:28 AM To: Robert Rutherford > Cc: MGB-V8 at autox.team.net ; MG Digest > Subject: Re: [Mgs] Coughing, spitting, and dying Sounds like a fuel problem. The Edelbrock 1404 is a simple carburetor to work on as it is a copy of the Carter AFB carb used since the 60?s. Is your choke set properly when cold and hot? The AFB used a mechanical fuel pump- make sure that facet pump you?re using has the correct fuel pressure for the AFB. Also check your vacuum. Is the vacuum reading steady or is the gauge needle fluctuating back and forth? You may have a vacuum leak affecting fuel mixture. When the engine is cold and the choke is on you have a rich mixture allowing the engine to run poorly. Once the choke opens the mixture goes lean due to the vacuum leak possibly leading to your motor stalling. Sent from my iPhone On Apr 23, 2022, at 11:10 PM, Robert Rutherford > wrote: ? Coughs, spits, dies - sounds like Covid to me. On Apr 21, 2022, at 12:34 PM, Max Heim > wrote: [?EXTERNAL] Sounds more like a carb/fuel issue to me. Can?t see how it would be electrical. Sent from my iPad On Apr 21, 2022, at 11:58 AM, jimray at hartcom.net wrote: ? Have an 80 MGB V8 conversion that has developed a problem I can?t get my hands around. When cold it coughs and sputters when first starting up and when warm will not run at idle without stalling after several minutes. Thinking it might be an electrical issue, I replaced the plugs, plug wires, distributor cap, coil, and battery. It has a PerTronix Ignitor module installed which I did not replace. The battery shows 12.7 volts on my meter. The alternator is producing 14.6 volts at ~1500 RPMs and 14.3 under load. Fuel is fed to an Edelbrock 1404 carburetor via a Facet electric pump with new filters in the line at the pump and just before the carburetor. I use 93 octane non-ethanol gas. I appreciate any thoughts or suggestions you may have. Jim Ray _______________________________________________ Mgs at autox.team.net Donate: http://www.team.net/donate.html Suggested annual donation $12.75 Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive Unsubscribe: http://autox.team.net/mailman/options/mgs/mvheim at sonic.net _______________________________________________ Mgs at autox.team.net Donate: http://www.team.net/donate.html Suggested annual donation $12.75 Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive Unsubscribe: http://autox.team.net/mailman/options/mgs/rrutherf at ucalgary.ca _______________________________________________ Mgs at autox.team.net Donate: http://www.team.net/donate.html Suggested annual donation $12.75 Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive Unsubscribe: http://autox.team.net/mailman/options/mgs/difejo1 at gmail.com -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus -------------- next part -------------- An HTML attachment was scrubbed... URL: From steve at shoyer.com Tue May 24 18:52:48 2022 From: steve at shoyer.com (Steve Shoyer) Date: Tue, 24 May 2022 20:52:48 -0400 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> Message-ID: <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> Hi - the radio in my 1980 MGB had been flaky for a while.? It would work with the key in the accessory position but not in the run position.? I could wiggle the key backwards and the radio would come on, but if I wiggled too far the engine would turn off.? I assumed that the ignition switch wasn't positioned properly but as long as I could get it to work I forgot about it by the time I got home. Until the radio wouldn't work at all.? No power was going to it. I tried to trace the white-green circuit and found that the white-green wire was melted about 2" from the ignition switch harness connector and the insulation had bonded the white-green to the other wires in the bundle.? The other wires didn't seem to be damaged, and I was able to peel the wires apart without any problem.? I repaired the burned section of white-green and tried it again, this time resulting smoke coming from the steering column.? The white-green wire had melted along most of its length. I had a spare ignition switch (not sure of its history, but maybe it came from a parts car) and swapped it in.? Strangely, it had a splice on the white-green wire near the connector.? It also started smoking. I tried to check the old spare switch (before it melted) to see how the switch worked but I didn't learn anything.? I also tried to see if there was voltage on any of the wires in the connector that mates with the ignition switch, thinking that power comes into the switch on the brown wire and is distributed to the other wires depending on the switch's position.? I grounded the black lead of my multimeter to the chassis and started looking for DC voltage on the other wires.? At first I didn't see anything, but when I touched one of the wires (I think white-red) the starter kicked in.? I stopped there. Any ideas as to what might be causing the wire to melt?? I didn't see any obvious problems with the wiring harness in the engine compartment, but it's very possible that I missed something. Also, when replacing the ignition switch, should I get an aftermarket switch or the Lucas switch?? The Lucas switch is about twice the cost of aftermarket so I'm leaning toward the aftermarket switch, especially if it might just burn up as soon as it's installed. Another odd thing is that the car ran fine when the radio wasn't working at all.? I didn't get smoke from the wiring, although by then the white-green wire was burned away before it left the ignition switch harness. Thanks. --Steve (1980 MGB) From paulhunt73 at virginmedia.com Fri May 27 01:55:14 2022 From: paulhunt73 at virginmedia.com (PaulHunt73) Date: Fri, 27 May 2022 08:55:14 +0100 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> Message-ID: The wire is smoking because whatever it's feeding is shorted to earth, so you will have to follow that wire to the radio.? If you have a fuse in the wire going into the radio then it's not the radio itself or that would have blown.? Assuming there IS a fuse in there and not a nail or something.? If no fuse then it could be the radio so disconnect it and try again, and if it still smokes the short is between that point and the visible melting of the white/green. It's not the switch that is faulty in this respect, although having been feeding a short-circuit the contacts in the switch may have been damaged.? It does sound as if the switch is iffy as well, maybe because of the short having been present in the past. So you need to find and fix the short before changing the switch or you are likely to damage that switch as well.? That wire should only go from the switch to the centre console for the radio ending at a bullet connector, it doesn't go via the engine compartment. PaulH. On 25/05/2022 01:52, Steve Shoyer wrote: > Hi - the radio in my 1980 MGB had been flaky for a while.? It would > work with the key in the accessory position but not in the run > position.? I could wiggle the key backwards and the radio would come > on, but if I wiggled too far the engine would turn off.? I assumed > that the ignition switch wasn't positioned properly but as long as I > could get it to work I forgot about it by the time I got home. > > Until the radio wouldn't work at all.? No power was going to it. I > tried to trace the white-green circuit and found that the white-green > wire was melted about 2" from the ignition switch harness connector > and the insulation had bonded the white-green to the other wires in > the bundle.? The other wires didn't seem to be damaged, and I was able > to peel the wires apart without any problem.? I repaired the burned > section of white-green and tried it again, this time resulting smoke > coming from the steering column.? The white-green wire had melted > along most of its length. > > I had a spare ignition switch (not sure of its history, but maybe it > came from a parts car) and swapped it in.? Strangely, it had a splice > on the white-green wire near the connector.? It also started smoking. > > I tried to check the old spare switch (before it melted) to see how > the switch worked but I didn't learn anything.? I also tried to see if > there was voltage on any of the wires in the connector that mates with > the ignition switch, thinking that power comes into the switch on the > brown wire and is distributed to the other wires depending on the > switch's position.? I grounded the black lead of my multimeter to the > chassis and started looking for DC voltage on the other wires.? At > first I didn't see anything, but when I touched one of the wires (I > think white-red) the starter kicked in.? I stopped there. > > Any ideas as to what might be causing the wire to melt?? I didn't see > any obvious problems with the wiring harness in the engine > compartment, but it's very possible that I missed something. Also, > when replacing the ignition switch, should I get an aftermarket switch > or the Lucas switch?? The Lucas switch is about twice the cost of > aftermarket so I'm leaning toward the aftermarket switch, especially > if it might just burn up as soon as it's installed. > > Another odd thing is that the car ran fine when the radio wasn't > working at all.? I didn't get smoke from the wiring, although by then > the white-green wire was burned away before it left the ignition > switch harness. > > Thanks. > > --Steve (1980 MGB) > > _______________________________________________ > > Mgs at autox.team.net > Donate: http://www.team.net/donate.html > Suggested annual donation? $12.75 > > Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive > > Unsubscribe: > http://autox.team.net/mailman/options/mgs/paulhunt73 at virginmedia.com From leon at zaks.com Fri May 27 09:09:00 2022 From: leon at zaks.com (leon at zaks.com) Date: Fri, 27 May 2022 11:09:00 -0400 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> Message-ID: Steve - I fully agree with PaulH. Though the switch may now be compromised but it's highly unlikely it was the cause. The cause is a short circuit in the green/white (G/W) wire. Though there is no fuse indicated in the wiring diagrams for the car there may be one in the lead from the radio to the bullet connector of the G/W wire. If there is a fuse and it is not blown then the short is between the fuse and the ignition switch. The G/W does not go through the firewall. There are some mildly sharp edges in the steering wheel supports that the wires run near - could be rubbing caused it or more likely someone working on the radio pulled it a bit much. Also - having had a few ignition switches apart the way it is built it would be very hard for it to be misaligned. What can happen is where the shaft from the key mechanism can wear the plastic of the actual switch and cause it to not connect properly - the "If I wiggle it it works" or "If I wiggle it it doesn't work" syndrome. I would replace the switch - after you find the problem. Last week I just purchased an aftermarket switch for my b - BPNorthwest has it for under $20, part number BHA5292. Here's my comments on what connects to what and why - I'm doing this to help anyone trouble shooting and ignition switch and also to reinforce it in my head. Brown (Br) wire is the 12v feed and is always hot. Slate is the anti-run on - power only when the key is off. G/W is accessory and running. The radio is connected to G/W so you can turn the radio on without the car running. White (W) is to the fuel pump (inertia switch first), overdrive, ignition system (with ignition relay on later models) and it feeds the Green wire going to most instruments, turn signals and the like. Red/white (R/W) is the power to the starter relay, seat belt module, hand brake, alternator warning lamp. On some models this wire doesn't go directly to the starter relay - it goes to the seat belt module so you can't start the car without buckling your seat belt :) Purple is the connection to the horn - it works opposite of the other wires - in the end of the connector coming from under the dash it is always 12v. The purple wire from the connect on the switch should go to ground when the horn is pressed. Here's a table of what should connect when on the switch. Position 1 is off, then progressively 2 is accessory, 3 is running, 4 is starting. You can test the switch by disconnecting the plug under the dash - connect one side of a meter or powered continuity tester to the brown wire and checking each of the other wires. Where there is an X you should get a connection. If not, the switch is bad. If you get a connection on a spot that does not have an X the switch is bad. Position???? S? G/W ?? W???? R/W?? Br? ? Purple ------------------------------------------------------------------------- 1??????????? |? X |??????? |????? |??????? |??? X? |?????????? | 2??????????? |???? |?? X?? |????? |??????? |??? X? |?????????? | 3??????????? |???? |?? X?? |? X? |??????? |??? X? |?????????? | 4??????????? |???? |??????? |? X? |?? X?? |??? X? |?????????? | leon ... https://leonsmgb.com On 5/27/22 3:55 AM, PaulHunt73 wrote: > The wire is smoking because whatever it's feeding is shorted to earth, > so you will have to follow that wire to the radio.? If you have a fuse > in the wire going into the radio then it's not the radio itself or > that would have blown.? Assuming there IS a fuse in there and not a > nail or something.? If no fuse then it could be the radio so > disconnect it and try again, and if it still smokes the short is > between that point and the visible melting of the white/green. > > It's not the switch that is faulty in this respect, although having > been feeding a short-circuit the contacts in the switch may have been > damaged.? It does sound as if the switch is iffy as well, maybe > because of the short having been present in the past. So you need to > find and fix the short before changing the switch or you are likely to > damage that switch as well.? That wire should only go from the switch > to the centre console for the radio ending at a bullet connector, it > doesn't go via the engine compartment. > > PaulH. > > > On 25/05/2022 01:52, Steve Shoyer wrote: >> Hi - the radio in my 1980 MGB had been flaky for a while.? It would >> work with the key in the accessory position but not in the run >> position.? I could wiggle the key backwards and the radio would come >> on, but if I wiggled too far the engine would turn off.? I assumed >> that the ignition switch wasn't positioned properly but as long as I >> could get it to work I forgot about it by the time I got home. >> >> Until the radio wouldn't work at all.? No power was going to it. I >> tried to trace the white-green circuit and found that the white-green >> wire was melted about 2" from the ignition switch harness connector >> and the insulation had bonded the white-green to the other wires in >> the bundle.? The other wires didn't seem to be damaged, and I was >> able to peel the wires apart without any problem.? I repaired the >> burned section of white-green and tried it again, this time resulting >> smoke coming from the steering column.? The white-green wire had >> melted along most of its length. >> >> I had a spare ignition switch (not sure of its history, but maybe it >> came from a parts car) and swapped it in.? Strangely, it had a splice >> on the white-green wire near the connector.? It also started smoking. >> >> I tried to check the old spare switch (before it melted) to see how >> the switch worked but I didn't learn anything.? I also tried to see >> if there was voltage on any of the wires in the connector that mates >> with the ignition switch, thinking that power comes into the switch >> on the brown wire and is distributed to the other wires depending on >> the switch's position.? I grounded the black lead of my multimeter to >> the chassis and started looking for DC voltage on the other wires.? >> At first I didn't see anything, but when I touched one of the wires >> (I think white-red) the starter kicked in.? I stopped there. >> >> Any ideas as to what might be causing the wire to melt?? I didn't see >> any obvious problems with the wiring harness in the engine >> compartment, but it's very possible that I missed something. Also, >> when replacing the ignition switch, should I get an aftermarket >> switch or the Lucas switch?? The Lucas switch is about twice the cost >> of aftermarket so I'm leaning toward the aftermarket switch, >> especially if it might just burn up as soon as it's installed. >> >> Another odd thing is that the car ran fine when the radio wasn't >> working at all.? I didn't get smoke from the wiring, although by then >> the white-green wire was burned away before it left the ignition >> switch harness. >> >> Thanks. >> >> --Steve (1980 MGB) >> >> _______________________________________________ >> >> Mgs at autox.team.net >> Donate: http://www.team.net/donate.html >> Suggested annual donation? $12.75 >> >> Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive >> >> Unsubscribe: >> http://autox.team.net/mailman/options/mgs/paulhunt73 at virginmedia.com > _______________________________________________ > > Mgs at autox.team.net > Donate: http://www.team.net/donate.html > Suggested annual donation? $12.75 > > Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive > > Unsubscribe: http://autox.team.net/mailman/options/mgs/leon at zaks.com -------------- next part -------------- A non-text attachment was scrubbed... Name: leon.vcf Type: text/vcard Size: 4 bytes Desc: not available URL: From paulhunt73 at virginmedia.com Fri May 27 09:41:22 2022 From: paulhunt73 at virginmedia.com (PaulHunt73) Date: Fri, 27 May 2022 16:41:22 +0100 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> Message-ID: <3fb16c40-ff3b-c4de-69a8-cb413999343f@virginmedia.com> Some amendments: White/red (not red/white, that is instrument illumination) from the ignition switch is for the starter.? The alternator warning lamp has a white wire from the ignition switch. Purple/pink on the ignition switch, not purple, for the 'key in, door open' warning and is at earth/ground when the key is in. Purple is the fused always hot supply from the fusebox to horns, courtesy lights, headlamp flasher etc. but not associated with the ignition switch. PaulH. On 27/05/2022 16:09, leon at zaks.com wrote: > Steve - I fully agree with PaulH. Though the switch may now be > compromised but it's highly unlikely it was the cause. The cause is a > short circuit in the green/white (G/W) wire. Though there is no fuse > indicated in the wiring diagrams for the car there may be one in the > lead from the radio to the bullet connector of the G/W wire. If there > is a fuse and it is not blown then the short is between the fuse and > the ignition switch. The G/W does not go through the firewall. > > There are some mildly sharp edges in the steering wheel supports that > the wires run near - could be rubbing caused it or more likely someone > working on the radio pulled it a bit much. > > Also - having had a few ignition switches apart the way it is built it > would be very hard for it to be misaligned. What can happen is where > the shaft from the key mechanism can wear the plastic of the actual > switch and cause it to not connect properly - the "If I wiggle it it > works" or "If I wiggle it it doesn't work" syndrome. > > I would replace the switch - after you find the problem. Last week I > just purchased an aftermarket switch for my b - BPNorthwest has it for > under $20, part number BHA5292. > > Here's my comments on what connects to what and why - I'm doing this > to help anyone trouble shooting and ignition switch and also to > reinforce it in my head. > > Brown (Br) wire is the 12v feed and is always hot. > > Slate is the anti-run on - power only when the key is off. > > G/W is accessory and running. The radio is connected to G/W so you can > turn the radio on without the car running. > > White (W) is to the fuel pump (inertia switch first), overdrive, > ignition system (with ignition relay on later models) and it feeds the > Green wire going to most instruments, turn signals and the like. > > Red/white (R/W) is the power to the starter relay, seat belt module, > hand brake, alternator warning lamp. On some models this wire doesn't > go directly to the starter relay - it goes to the seat belt module so > you can't start the car without buckling your seat belt :) > > Purple is the connection to the horn - it works opposite of the other > wires - in the end of the connector coming from under the dash it is > always 12v. The purple wire from the connect on the switch should go > to ground when the horn is pressed. > > Here's a table of what should connect when on the switch. > Position 1 is off, then progressively 2 is accessory, 3 is running, 4 > is starting. > > You can test the switch by disconnecting the plug under the dash - > connect one side of a meter or powered continuity tester to the brown > wire and checking each of the other wires. Where there is an X you > should get a connection. If not, the switch is bad. If you get a > connection on a spot that does not have an X the switch is bad. > > Position???? S? G/W ?? W???? R/W?? Br? ? Purple > ------------------------------------------------------------------------- > 1??????????? |? X |??????? |????? |??????? |??? X? |?????????? | > 2??????????? |???? |?? X?? |????? |??????? |??? X? |?????????? | > 3??????????? |???? |?? X?? |? X? |??????? |??? X? |?????????? | > 4??????????? |???? |??????? |? X? |?? X?? |??? X? |?????????? | > > leon ... > https://leonsmgb.com > From leon at zaks.com Fri May 27 09:59:07 2022 From: leon at zaks.com (leon at zaks.com) Date: Fri, 27 May 2022 11:59:07 -0400 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: <3fb16c40-ff3b-c4de-69a8-cb413999343f@virginmedia.com> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> <3fb16c40-ff3b-c4de-69a8-cb413999343f@virginmedia.com> Message-ID: <86023c78-43cc-d8f7-83af-05ebba3f0f5b@zaks.com> agreed. On 5/27/22 11:41 AM, PaulHunt73 wrote: > Some amendments: > > White/red (not red/white, that is instrument illumination) from the > ignition switch is for the starter.? The alternator warning lamp has a > white wire from the ignition switch. > > Purple/pink on the ignition switch, not purple, for the 'key in, door > open' warning and is at earth/ground when the key is in. Purple is the > fused always hot supply from the fusebox to horns, courtesy lights, > headlamp flasher etc. but not associated with the ignition switch. > > PaulH. > > On 27/05/2022 16:09, leon at zaks.com wrote: >> Steve - I fully agree with PaulH. Though the switch may now be >> compromised but it's highly unlikely it was the cause. The cause is a >> short circuit in the green/white (G/W) wire. Though there is no fuse >> indicated in the wiring diagrams for the car there may be one in the >> lead from the radio to the bullet connector of the G/W wire. If there >> is a fuse and it is not blown then the short is between the fuse and >> the ignition switch. The G/W does not go through the firewall. >> >> There are some mildly sharp edges in the steering wheel supports that >> the wires run near - could be rubbing caused it or more likely >> someone working on the radio pulled it a bit much. >> >> Also - having had a few ignition switches apart the way it is built >> it would be very hard for it to be misaligned. What can happen is >> where the shaft from the key mechanism can wear the plastic of the >> actual switch and cause it to not connect properly - the "If I wiggle >> it it works" or "If I wiggle it it doesn't work" syndrome. >> >> I would replace the switch - after you find the problem. Last week I >> just purchased an aftermarket switch for my b - BPNorthwest has it >> for under $20, part number BHA5292. >> >> Here's my comments on what connects to what and why - I'm doing this >> to help anyone trouble shooting and ignition switch and also to >> reinforce it in my head. >> >> Brown (Br) wire is the 12v feed and is always hot. >> >> Slate is the anti-run on - power only when the key is off. >> >> G/W is accessory and running. The radio is connected to G/W so you >> can turn the radio on without the car running. >> >> White (W) is to the fuel pump (inertia switch first), overdrive, >> ignition system (with ignition relay on later models) and it feeds >> the Green wire going to most instruments, turn signals and the like. >> >> Red/white (R/W) is the power to the starter relay, seat belt module, >> hand brake, alternator warning lamp. On some models this wire doesn't >> go directly to the starter relay - it goes to the seat belt module so >> you can't start the car without buckling your seat belt :) >> >> Purple is the connection to the horn - it works opposite of the other >> wires - in the end of the connector coming from under the dash it is >> always 12v. The purple wire from the connect on the switch should go >> to ground when the horn is pressed. >> >> Here's a table of what should connect when on the switch. >> Position 1 is off, then progressively 2 is accessory, 3 is running, 4 >> is starting. >> >> You can test the switch by disconnecting the plug under the dash - >> connect one side of a meter or powered continuity tester to the brown >> wire and checking each of the other wires. Where there is an X you >> should get a connection. If not, the switch is bad. If you get a >> connection on a spot that does not have an X the switch is bad. >> >> Position???? S? G/W ?? W???? R/W?? Br? ? Purple >> ------------------------------------------------------------------------- >> >> 1??????????? |? X |??????? |????? |??????? |??? X? |?????????? | >> 2??????????? |???? |?? X?? |????? |??????? |??? X? |?????????? | >> 3??????????? |???? |?? X?? |? X? |??????? |??? X? |?????????? | >> 4??????????? |???? |??????? |? X? |?? X?? |??? X? |?????????? | >> >> leon ... >> https://leonsmgb.com >> > _______________________________________________ > > Mgs at autox.team.net > Donate: http://www.team.net/donate.html > Suggested annual donation? $12.75 > > Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive > > Unsubscribe: http://autox.team.net/mailman/options/mgs/leon at zaks.com -------------- next part -------------- A non-text attachment was scrubbed... Name: leon.vcf Type: text/vcard Size: 4 bytes Desc: not available URL: From h.duinhoven at planet.nl Sat May 28 02:43:13 2022 From: h.duinhoven at planet.nl (h.duinhoven at planet.nl) Date: Sat, 28 May 2022 10:43:13 +0200 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> Message-ID: <003101d8726e$f821e6d0$e865b470$@planet.nl> Hi Steve, The burnt wire only is a feed to the radio - see this part of the diagram. It seems, that the radio itself is making a short to ground. Pity two ignition switches have been damaged by this. The problem with MGB?s is that many parts of the wiring are poorly protected against short circuits. Another radio is easy to find I think. If you want to preserve the radio because of originality, it should be repaired. Hope this helps. Cheers, Hans 71 BGT -----Oorspronkelijk bericht----- Van: Mgs Namens Steve Shoyer Verzonden: Wednesday, 25 May 2022 02:53 Aan: mgs at autox.team.net Onderwerp: [Mgs] 80B, melted white-green wire from ignition switch Hi - the radio in my 1980 MGB had been flaky for a while. It would work with the key in the accessory position but not in the run position. I could wiggle the key backwards and the radio would come on, but if I wiggled too far the engine would turn off. I assumed that the ignition switch wasn't positioned properly but as long as I could get it to work I forgot about it by the time I got home. Until the radio wouldn't work at all. No power was going to it. I tried to trace the white-green circuit and found that the white-green wire was melted about 2" from the ignition switch harness connector and the insulation had bonded the white-green to the other wires in the bundle. The other wires didn't seem to be damaged, and I was able to peel the wires apart without any problem. I repaired the burned section of white-green and tried it again, this time resulting smoke coming from the steering column. The white-green wire had melted along most of its length. I had a spare ignition switch (not sure of its history, but maybe it came from a parts car) and swapped it in. Strangely, it had a splice on the white-green wire near the connector. It also started smoking. I tried to check the old spare switch (before it melted) to see how the switch worked but I didn't learn anything. I also tried to see if there was voltage on any of the wires in the connector that mates with the ignition switch, thinking that power comes into the switch on the brown wire and is distributed to the other wires depending on the switch's position. I grounded the black lead of my multimeter to the chassis and started looking for DC voltage on the other wires. At first I didn't see anything, but when I touched one of the wires (I think white-red) the starter kicked in. I stopped there. Any ideas as to what might be causing the wire to melt? I didn't see any obvious problems with the wiring harness in the engine compartment, but it's very possible that I missed something. Also, when replacing the ignition switch, should I get an aftermarket switch or the Lucas switch? The Lucas switch is about twice the cost of aftermarket so I'm leaning toward the aftermarket switch, especially if it might just burn up as soon as it's installed. Another odd thing is that the car ran fine when the radio wasn't working at all. I didn't get smoke from the wiring, although by then the white-green wire was burned away before it left the ignition switch harness. Thanks. --Steve (1980 MGB) _______________________________________________ Mgs at autox.team.net Donate: http://www.team.net/donate.html Suggested annual donation $12.75 Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive Unsubscribe: http://autox.team.net/mailman/options/mgs/h.duinhoven at planet.nl -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: image001.png Type: image/png Size: 54740 bytes Desc: not available URL: From dave at ranteer.com Sat May 28 14:20:20 2022 From: dave at ranteer.com (dave northrup) Date: Sat, 28 May 2022 20:20:20 +0000 Subject: [Mgs] 1972 MG MGB Roadster on BaT Message-ID: <9a4c9f654b8b4cc786b3be563207199f@ranteer.com> https://bringatrailer.com/listing/1972-mg-mgb-41/ my adult son is selling his car; we are working on an MGA. Its as nice as it looks -------------- next part -------------- An HTML attachment was scrubbed... URL: From steve at shoyer.com Tue May 31 02:08:55 2022 From: steve at shoyer.com (Steve Shoyer) Date: Tue, 31 May 2022 04:08:55 -0400 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> Message-ID: <306eddaa-9a8f-cc3f-eb9b-de95980ea17d@shoyer.com> Thanks to everyone who replied to my question.? I think I understand what probably happened.? I think the bullet connection between the white-green feed to the radio and the radio's wiring harness (which had an inline fuse) must have loosened and allowed the bare connector to short to ground, possibly on the heater control cable. When I removed the radio, there was no longer continuity between the white-green connector coming from the ignition switch and ground.? I replaced the ignition switch with a new aftermarket one, and I also replaced the radio.? The one that I had been using seemed fine, but it had a CD player so it was about 6" deep.? I picked up a new one without a CD player (a Jensen unit with Bluetooth for $36) that's less than 2" deep, so there's a lot more room behind the radio and it should be less likely to cause strain on the wiring.? This radio uses the same style of wiring harness as my old one so it was an easy swap.? Nothing melted when I tried the new switch and radio, so I think I'm good now.? I might try to use a zip-tie to hold the radio wiring in place and reduce the possibility of pulling the power connection apart.? I put in a 5A fuse for the switched power rather than the 10A fuse that came with the radio, hoping that it would blow quickly if there was a short somewhere in the circuit that I didn't see. --Steve (1980 MGB) From paulhunt73 at virginmedia.com Tue May 31 04:13:27 2022 From: paulhunt73 at virginmedia.com (PaulHunt73) Date: Tue, 31 May 2022 11:13:27 +0100 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: <306eddaa-9a8f-cc3f-eb9b-de95980ea17d@shoyer.com> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> <306eddaa-9a8f-cc3f-eb9b-de95980ea17d@shoyer.com> Message-ID: 5A or 10A, or even the original 17A, would protect the cars wiring in the event of a short but it needs to be as close to the supply i.e. at the ignition switch to do that.? Fuses in the wires that go into the radio are there to prevent very thin internal wires from actually burning in the event of an internal short, they won't protect the cars wiring if the short is on the supply side of that fuse.? So if the same fault should happen again, you will get the same result. PaulH. On 31/05/2022 09:08, Steve Shoyer wrote: > I put in a 5A fuse for the switched power rather than the 10A fuse > that came with the radio, hoping that it would blow quickly if there > was a short somewhere in the circuit that I didn't see. > From mgbobh at gmail.com Tue May 31 05:44:25 2022 From: mgbobh at gmail.com (Robert's New iPad) Date: Tue, 31 May 2022 07:44:25 -0400 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> <306eddaa-9a8f-cc3f-eb9b-de95980ea17d@shoyer.com> Message-ID: <98139F1B-6D55-41F0-8E34-8DF2C993B6DE@gmail.com> In the Jan/Feb 2022 issue of MG Driver, David Wright, of Southern British Car Club, wrote a useful article about fuses. He noted that the fuse rating standards were changed in 1980, from the rating being the ?blow? current to the rating now being ?operating current. It is an interesting article, with graphs and all, with the takeaway being that we owners of pre 1980 cars must be especially careful that the modern fuses we buy are not stronger than we realise. His conclusion is that the modern AGC 15 and 3AGC 15 are the available equivalent of the Lucas 35 amp fuses; the modern SFE 20 or AGC 20 the equivalent of Lucas 50 amp fuses. All MGB drivers have installed an inline fuse into both fuel pump and overdrive wires, haven?t we? Bob > On May 31, 2022, at 6:13 AM, PaulHunt73 wrote: > > 5A or 10A, or even the original 17A, would protect the cars wiring in the event of a short but it needs to be as close to the supply i.e. at the ignition switch to do that. Fuses in the wires that go into the radio are there to prevent very thin internal wires from actually burning in the event of an internal short, they won't protect the cars wiring if the short is on the supply side of that fuse. So if the same fault should happen again, you will get the same result. > > PaulH. > >> On 31/05/2022 09:08, Steve Shoyer wrote: >> I put in a 5A fuse for the switched power rather than the 10A fuse that came with the radio, hoping that it would blow quickly if there was a short somewhere in the circuit that I didn't see. >> > _______________________________________________ > > Mgs at autox.team.net > Donate: http://www.team.net/donate.html > Suggested annual donation $12.75 > > Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive > > Unsubscribe: http://autox.team.net/mailman/options/mgs/mgbobh at gmail.com From paulhunt73 at virginmedia.com Tue May 31 06:01:25 2022 From: paulhunt73 at virginmedia.com (PaulHunt73) Date: Tue, 31 May 2022 13:01:25 +0100 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: <98139F1B-6D55-41F0-8E34-8DF2C993B6DE@gmail.com> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> <306eddaa-9a8f-cc3f-eb9b-de95980ea17d@shoyer.com> <98139F1B-6D55-41F0-8E34-8DF2C993B6DE@gmail.com> Message-ID: <394e33ea-d01d-6822-680e-02caa4b860ab@virginmedia.com> The original 17/35 fuses are still available in the UK, often (but not always) showing both figures.? You do have to be careful to get the correct one where only one figure is shown, I have some examples where it is the higher figure i.e. the 'blow' figure and not the 'continuous' that is shown. "All MGB drivers have installed an inline fuse into both fuel pump and overdrive wires, haven?t we?" Ha ha, I doubt it!? I have both by the heater shelf on my V8, which proved very useful when I had a sunk carb float.? I cross-connected the two and used the overdrive switch to turn the fuel pump on and off as needed. PaulH. On 31/05/2022 12:44, Robert's New iPad wrote: > In the Jan/Feb 2022 issue of MG Driver, David Wright, of Southern British Car Club, wrote a useful article about fuses. > He noted that the fuse rating standards were changed in 1980, from the rating being the ?blow? current to the rating now being ?operating current. It is an interesting article, with graphs and all, with the takeaway being that we owners of pre 1980 cars must be especially careful that the modern fuses we buy are not stronger than we realise. > His conclusion is that the modern AGC 15 and 3AGC 15 are the available equivalent of the Lucas 35 amp fuses; the modern SFE 20 or AGC 20 the equivalent of Lucas 50 amp fuses. > All MGB drivers have installed an inline fuse into both fuel pump and overdrive wires, haven?t we? > Bob > > From mgbobh at gmail.com Tue May 31 06:07:57 2022 From: mgbobh at gmail.com (Robert's New iPad) Date: Tue, 31 May 2022 08:07:57 -0400 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: <394e33ea-d01d-6822-680e-02caa4b860ab@virginmedia.com> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> <306eddaa-9a8f-cc3f-eb9b-de95980ea17d@shoyer.com> <98139F1B-6D55-41F0-8E34-8DF2C993B6DE@gmail.com> <394e33ea-d01d-6822-680e-02caa4b860ab@virginmedia.com> Message-ID: That cross-connection is a clever idea. It would have been useful for a friend, just a week or two ago, whose front HIF float sank. I will suggest that to him, and look to see how easily that might be accomplished in my car. > On May 31, 2022, at 8:01 AM, PaulHunt73 wrote: > > The original 17/35 fuses are still available in the UK, often (but not always) showing both figures. You do have to be careful to get the correct one where only one figure is shown, I have some examples where it is the higher figure i.e. the 'blow' figure and not the 'continuous' that is shown. > > "All MGB drivers have installed an inline fuse into both fuel pump and overdrive wires, haven?t we?" > > Ha ha, I doubt it! I have both by the heater shelf on my V8, which proved very useful when I had a sunk carb float. I cross-connected the two and used the overdrive switch to turn the fuel pump on and off as needed. > > PaulH. > >> On 31/05/2022 12:44, Robert's New iPad wrote: >> In the Jan/Feb 2022 issue of MG Driver, David Wright, of Southern British Car Club, wrote a useful article about fuses. >> He noted that the fuse rating standards were changed in 1980, from the rating being the ?blow? current to the rating now being ?operating current. It is an interesting article, with graphs and all, with the takeaway being that we owners of pre 1980 cars must be especially careful that the modern fuses we buy are not stronger than we realise. >> His conclusion is that the modern AGC 15 and 3AGC 15 are the available equivalent of the Lucas 35 amp fuses; the modern SFE 20 or AGC 20 the equivalent of Lucas 50 amp fuses. >> All MGB drivers have installed an inline fuse into both fuel pump and overdrive wires, haven?t we? >> Bob >> >> From paulhunt73 at virginmedia.com Tue May 31 07:10:12 2022 From: paulhunt73 at virginmedia.com (PaulHunt73) Date: Tue, 31 May 2022 14:10:12 +0100 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> <306eddaa-9a8f-cc3f-eb9b-de95980ea17d@shoyer.com> <98139F1B-6D55-41F0-8E34-8DF2C993B6DE@gmail.com> <394e33ea-d01d-6822-680e-02caa4b860ab@virginmedia.com> Message-ID: <2ef4f9de-000b-cc89-8f48-96074390e026@virginmedia.com> That was the most convenient position for connecting the OD fuse on the 75 V8 without cutting wires, and fortuitous.? On the 73 with dash OD switch I had fitted the fuse at the switch, so cross-connecting the fuses isn't directly possible.? However for most years the same effect can be obtained by swapping over the white and yellow wires at the bullet connectors in the engine bay, including where fuses have not been fitted in either circuit.? On later North American models with OD on 4th gear only it would involve white and white/brown wires. PaulH. On 31/05/2022 13:07, Robert's New iPad wrote: > That cross-connection is a clever idea. It would have been useful for a friend, just a week or two ago, whose front HIF float sank. I will suggest that to him, and look to see how easily that might be accomplished in my car. > > From h.duinhoven at planet.nl Tue May 31 13:47:09 2022 From: h.duinhoven at planet.nl (h.duinhoven at planet.nl) Date: Tue, 31 May 2022 21:47:09 +0200 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: <306eddaa-9a8f-cc3f-eb9b-de95980ea17d@shoyer.com> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> <306eddaa-9a8f-cc3f-eb9b-de95980ea17d@shoyer.com> Message-ID: <002201d87527$3749fe00$a5ddfa00$@planet.nl> Oh that darn heater cable again - it made a short in my GT as well after it went lose from its control position! -----Oorspronkelijk bericht----- Van: Mgs Namens Steve Shoyer Verzonden: Tuesday, 31 May 2022 10:09 Aan: mgs at autox.team.net Onderwerp: Re: [Mgs] 80B, melted white-green wire from ignition switch Thanks to everyone who replied to my question. I think I understand what probably happened. I think the bullet connection between the white-green feed to the radio and the radio's wiring harness (which had an inline fuse) must have loosened and allowed the bare connector to short to ground, possibly on the heater control cable. When I removed the radio, there was no longer continuity between the white-green connector coming from the ignition switch and ground. I replaced the ignition switch with a new aftermarket one, and I also replaced the radio. The one that I had been using seemed fine, but it had a CD player so it was about 6" deep. I picked up a new one without a CD player (a Jensen unit with Bluetooth for $36) that's less than 2" deep, so there's a lot more room behind the radio and it should be less likely to cause strain on the wiring. This radio uses the same style of wiring harness as my old one so it was an easy swap. Nothing melted when I tried the new switch and radio, so I think I'm good now. I might try to use a zip-tie to hold the radio wiring in place and reduce the possibility of pulling the power connection apart. I put in a 5A fuse for the switched power rather than the 10A fuse that came with the radio, hoping that it would blow quickly if there was a short somewhere in the circuit that I didn't see. --Steve (1980 MGB) _______________________________________________ Mgs at autox.team.net Donate: http://www.team.net/donate.html Suggested annual donation $12.75 Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive Unsubscribe: http://autox.team.net/mailman/options/mgs/h.duinhoven at planet.nl -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus From mgbobh at gmail.com Tue May 31 14:06:30 2022 From: mgbobh at gmail.com (Robert's New iPad) Date: Tue, 31 May 2022 16:06:30 -0400 Subject: [Mgs] 80B, melted white-green wire from ignition switch In-Reply-To: <002201d87527$3749fe00$a5ddfa00$@planet.nl> References: <661B54CB-60CC-439C-B7B4-F86C83CFBE5C@ucalgary.ca> <85DFECF2-AEE7-4C47-B8BC-530346060E71@gmail.com> <001a01d8629f$7fb54d60$7f1fe820$@planet.nl> <40e6593a-e23f-523c-82a8-9737a051d61e@shoyer.com> <306eddaa-9a8f-cc3f-eb9b-de95980ea17d@shoyer.com> <002201d87527$3749fe00$a5ddfa00$@planet.nl> Message-ID: Fried heater cable is usually because the earth strap(s) from engine to body are not conducting properly. I have two on my GT, and check their fasteners a couple of times each year. Bob > On May 31, 2022, at 3:47 PM, wrote: > > Oh that darn heater cable again - it made a short in my GT as well after it went lose from its control position! > > -----Oorspronkelijk bericht----- > Van: Mgs Namens Steve Shoyer > Verzonden: Tuesday, 31 May 2022 10:09 > Aan: mgs at autox.team.net > Onderwerp: Re: [Mgs] 80B, melted white-green wire from ignition switch > > Thanks to everyone who replied to my question. I think I understand what probably happened. I think the bullet connection between the white-green feed to the radio and the radio's wiring harness (which had an inline fuse) must have loosened and allowed the bare connector to short to ground, possibly on the heater control cable. When I removed the radio, there was no longer continuity between the white-green connector coming from the ignition switch and ground. I replaced the ignition switch with a new aftermarket one, and I also replaced the radio. The one that I had been using seemed fine, but it had a CD player so it was about 6" deep. I picked up a new one without a CD player (a Jensen unit with Bluetooth for $36) that's less than 2" deep, so there's a lot more room behind the radio and it should be less likely to cause strain on the wiring. This radio uses the same style of wiring harness as my old one so it was an easy swap. Nothing melted when I tried the new switch and > radio, so I think I'm good now. I might try to use a zip-tie to hold the radio wiring in place and reduce the possibility of pulling the power connection apart. I put in a 5A fuse for the switched power rather than the 10A fuse that came with the radio, hoping that it would blow quickly if there was a short somewhere in the circuit that I didn't see. > > --Steve (1980 MGB) > > _______________________________________________ > > Mgs at autox.team.net > Donate: http://www.team.net/donate.html > Suggested annual donation $12.75 > > Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive > > Unsubscribe: http://autox.team.net/mailman/options/mgs/h.duinhoven at planet.nl > > > -- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus > > _______________________________________________ > > Mgs at autox.team.net > Donate: http://www.team.net/donate.html > Suggested annual donation $12.75 > > Archive: http://www.team.net/pipermail/mgs http://autox.team.net/archive > > Unsubscribe: http://autox.team.net/mailman/options/mgs/mgbobh at gmail.com