[TR] Backfiring! Help!

[Joe Burlein]

Brian Induni wrote:
> I've seen a faulty coil cause similar symptoms. Best diagnosis procedure is
> to try one thing at a time - start with a NEW (not one off the "spare parts"
> shelf...) coil and recheck the timing. Set the static timing manually - #1 @
> TDC and set the disti to fire at that point. 
OK, how do you properly do that?  With a light, no problem.  Without...
> If backfiring thru the intake,
> then the timing is too far advanced. Don't rely on a strobe! Then check the
> plug wires -if there's cross talk, they could be firing at wrong times. My 2
> shilings...
>
> Brian
> 1967 TR4a
>
>
> ------------------------------
>
> Message: 3
> Date: Mon, 19 Nov 2007 08:42:49 -0500
> From: Joe Burlein <supertr6 at earthlink.net>
> Subject: Re: [TR] Backfiring! Help!
> To: Mitch <ms6453 at optonline.net>, Triumph List
> 	<triumphs at autox.team.net>
> Message-ID: <474192D9.9000808 at earthlink.net>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Mitch wrote:
>   
>> Hi Joe,
>>
>> To get a better idea of the problem more info is needed.
>> Does it backfire under load, if so when hot or cold.
>>     
> Originally under load and when cold, now under idle conditions.
>   
>> Is it back firing through the intake or exhaust?
>>     
> Intake
>   
>> Did you put points in and eliminate the electronic ignition?
>>     
> Not yet, she won't even idle now.  This was going to be the next thing I 
> did as far as troubleshooting before the backfiring at idle happended.
>   
>> What do the plugs look like?
>>     
> Fine, but, they are new.  The old ones had the normal color range.
>   
>> What does your vacuum gauge read.
>>     
> If are speaking of the PSI gauge, then 0.
>   
>> If you have an 02 sensor with a fuel/air mixture what does that read.
>>     
> N/A, sorry.
>   
>> Did this occur after any changes?
>>     
> No.
>   
>> Any other symptoms, hunting  or surging idle,  hard starting, 
>> hesitation, stumbling.
>>     
> The only symptom I had before the backfiring was a cut out at high RPM 
> and hard acceleration.  That was what made me start to question (after 
> checking plugs, timing, car leaks, vacuum leaks) the Pertronix.  I just 
> never got around to swapping it out.
>
> Thanks for the help Mitch.
>
> Joe
>   
>>  
>> -- 
>> Mitch Seff
>> Oceanside, N.Y.
>> 75 TR6 SC
>> http://www.triumphowners.com/384
>>     
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