[Fot] Help needed, TR250 engine rebuild oil pressure problems

EDWARD BARNARD edwardbarnard at prodigy.net
Sun Sep 15 21:40:59 MDT 2013 

Group:
I will throw my 2 cents in. Had the same problem with a customers engine. He had someone build an engine which then showed your symptoms. The builder rebuilt it again, only to have the same symptoms again. This is when he came to me. I thought cam bearings (lack of) for sure and tore the motor down. Took it to the shop to be vatted and have bearings installed, only to have the machinest call and tell me that there was a crack in the block through the oil passage on one of the crank mains.  A replacement block solved the issue. The pump created enough pressure at rpm, but not at idle. The oil just pumps back into the sump. Similar to having the pressure relief valve stuck open just a little, like if something is stuck in the valve. Check the valve first...look into the passage for anything preventing it from closing all the way. Hard to get down there with the engine in the car.
Keep us informed.
-Ed-
 

________________________________
 From: DuaneBailey <dbailey_wmi at yahoo.com>
To: Duncan Charlton <duncan.charlton54 at gmail.com> 
Cc: "fot at autox.team.net" <fot at autox.team.net> 
Sent: Sunday, September 15, 2013 7:54 PM
Subject: Re: [Fot] Help needed, TR250 engine rebuild oil pressure problems
  


I assume you didn't bore the block & install cam bearings. Your problem is excessive clearence beween the cam & block & that is bleeding off all your oil pressure. I will not rebuild a race or street 6 cyl engine without boring the block & installing cam bearings. The bearings for a mk2/3 Spit work perfectly.

Sent from my iPad

On Sep 15, 2013, at 3:56 PM, Duncan Charlton <duncan.charlton54 at gmail.com> wrote:


I'm not sure that's worst case -- the bearings, either crank or cam bearings, could have too much clearance and that would require a full teardown, ye that doesn't seem likely if the engine rebuilder followed long-established practices.  One other item that hasn't been mentioned yet -- are you using an oil cooler with a thermostatic valve?  If it was installed improperly perhaps there's a way it could rob pressure from the system when the oil heats up and the valve opens.
>
>
>Duncan
>(Texas)
>
>
>
>
>On Sep 15, 2013, at 10:13 AM, robertten1 at aol.com wrote:
>
>
>>
>>
>>
>>-----Original Message-----
>>From: robertten1 <robertten1 at aol.com>
>>To: tr4racing <tr4racing at googlemail.com>
>>Sent: Sun, Sep 15, 2013 11:11 am
>>Subject: Re: [Fot] Help needed, TR250 engine rebuild oil pressure problems
>>
>>
>>Did you replace the Oil Pressure Releif Valve and its Spring ?  I would first hook up a mechanical test pressure guage at the Oil Pressure Switch in the block and see what readings you get.  Worse case ... the Pump could be at fault.  Lastly are you running the cannister filter or a spin on oil filter? 
>>
>>Best o Luck 
>>Bob T
>>
>>
>> 
>>-----Original Message-----
>>From: MadMarx <tr4racing at googlemail.com>
>>To: 'Andrew Packard' <apackard68 at att.net>; '6 Digest' <6pack at autox.team.net>; fot <fot at autox.team.net>
>>Sent: Sun, Sep 15, 2013 5:53 am
>>Subject: Re: [Fot] Help needed, TR250 engine rebuild oil pressure problems
>>
>>
>>Could there any trouble with the pressure relive valve?
I'm not familiar with the 6 pot engines. Chris -----Ursprüngliche Nachricht-----
Von: fot-bounces at autox.team.net [mailto:fot-bounces at autox.team.net] Im
Auftrag von Andrew Packard
Gesendet: Sonntag, 15. September 2013 02:56
An: 6 Digest; fot at autox.team.net Betreff: [Fot] Help needed, TR250 engine rebuild oil pressure problems Hello Triumph problem solvers. I nearly have my TR250 ready for Triumphest/VTR after an engine rebuild.
I'm trying to solve a problem now with maintaining consistent oil pressure.
When I first ran the car after the rebuild, the 20 minutes at 2000 rpm
start, I had Castrol 5W30 and ZDDP additive.  After the engine really got up
to temperature, I had trouble with maintaining oil pressure, dropping way
down close to zero at idle.  A mechanic friend of mine checked it out with
me and with the rocker cover off, we saw little flow at the rockers at idle.
I had an external oiling line on my shelf so I added that and saw very good
flow at start up when oil pressure was about 65 and settled down to just
under 50 as it started to get warm, but continued to drop to the same near
zero level once it was at temperature.   Today I changed the oil to 20W50 Castrol with Lucas ZDDP break-in additive.
Same symptoms.  I drove the car about four miles near my house and at
temperature, I was running at 20-25 psi when driving, dropping to near zero
at stop signs.  When I arrived home, I removed the quite hot valve cover oil
fill cap and started the car.  Very little oil was dancing around, if any,
at idle.  I revved the car a bit and saw sufficient oil flowing and
splattering in there.   Now I don't know what to do.  I have the braided oil pressure line from TSI.
I don't think my gauge is bad with oil flow symptoms consistent with the
pressure readings.  Could the oil pressure regulator be an issue?  Mine is
relatively new from BPNW.  I do have a second one I could swap in.  The oil
pump was new with the rebuild.   Any advice or guidance is appreciated.   Andy Packard
CD6746L
President - Triumph Travelers
Autocross Chair - 2013 Triumphest/VTR _______________________________________________ fot at autox.team.net http://www.fot-racing.com Donate: http://www.team.net/donate.html Archive: http://www.team.net/archive Forums: http://www.team.net/forums Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/tr4racing@googlemail.com _______________________________________________ fot at autox.team.net http://www.fot-racing.com Donate: http://www.team.net/donate.html Archive: http://www.team.net/archive Forums: http://www.team.net/forums Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/robertten1@aol.com     _______________________________________________
>>fot at autox.team.net
>>
>>http://www.fot-racing.com/
>>
>>Donate: http://www.team.net/donate.html
>>Archive: http://www.team.net/archive
>>Forums: http://www.team.net/forums
>>Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/duncan.charlton54@gmail.com
>>
>>
>>
>
_______________________________________________
>fot at autox.team.net
>
>http://www.fot-racing.com/
>
>Donate: http://www.team.net/donate.html
>Archive: http://www.team.net/archive
>Forums: http://www.team.net/forums
>Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/dbailey_wmi@yahoo.com
>
>
>
_______________________________________________
fot at autox.team.net

http://www.fot-racing.com/

Donate: http://www.team.net/donate.html
Archive: http://www.team.net/archive
Forums: http://www.team.net/forums
Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/edwardbarnard@prodigy.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/fot/attachments/20130915/0b6ef87b/attachment-0001.htm>

More information about the Fot mailing list