TR4/4A Missing since rebuild with Pertronix

[richie]

A couple years back I had my distributor completely overhauled by Jeff @ Advanced Distributors. After finally driving the car more and more I've began to experience a missing/sputtering when hot issue which I thought to be vapour lock due to ethanol rich gas.

After revising my distributor I am thinking perhaps there are some signs that the rotor is still sitting too high - but I'm not sure that this could cause the sputtering I am experiencing?

Anybody been down this road before? I've already shaved off some material off the bottom of the rotor (as per Jeff's recommendation last year) but the problem keeps coming back, this time without a warm or heat-soaked engine...

Thank you!

 

[richie]

Update, I since went to re-measure things and found my rotor was still sitting between 1/16->1/8" higher than without the Pertronix ring sitting below. I shaved enough material off to make it sit at it's normal height.

I was going to delete this thread but instead I will update this thread if the problem is fixed for future reference! Hopefully this is the fix...

 

[malbaby]

I found that a Pertronix distributor cap that I bought a while ago was poorly made [ not made in USA now], and not a tight fit onto the distributor.
May be it is your distributor cap that is faulty.

 

[NutmegCT]

Update, I since went to re-measure things and found my rotor was still sitting between 1/16->1/8" higher than without the Pertronix ring sitting below. I shaved enough material off to make it sit at it's normal height.

I was going to delete this thread but instead I will update this thread if the problem is fixed for future reference! Hopefully this is the fix...

Yes, please do update and let us know if there's a change. If the poor performance now occurs even when the engine isn't fully warmed up, there's obviously no vapor lock issue. In that previous thread you linked, did you follow up on checking those carb vent ports? (And of course, I always get back to the "replace the points, condenser, and coil" procedure, for sputtering at high rpm, if you've eliminated fuel flow as an issue.)

Inquiring minds want to know!

Tom

 

[Gliderman8]

Have you looked at your coil?

 

[charleyf]

get back to the "replace the points, condenser, and coil" procedure, for sputtering at high rpm, if you've eliminated fuel flow as an issue.)
Tom

I would add that spark plug wires can cause the very same thing problem.
Charley

 

[NutmegCT]

I would add that spark plug wires can cause the very same thing problem.
Charley

Charley - agree with you on that! On my TR3 I had a similar "missing at high speed" issue, and it turned out to be that one wire was just barely contacting the terminal in the rubber boot that fits over the plug. Finding that was quite an adventure, as the problem only occurred at high speed (bouncing over the road, etc.).

Also of course, a cracked wire covering can cause similar problems.

 

[RJS]

I have a pertronix ignition. Works really well. But, a couple of years ago I had a misfire issue when hot and under any load. When cool it was fine. Turned out to be a lower quality ignition rotor which was allowing arching inside the cap. Replaced the rotor with a top quality "red" rotor and all was well.

I see from the photo you already have a red rotor. But, it appears to have some dark patches on it which, to me, indicates arching.

Bob

 

[richie]

Well, since shaving it down to match the height without the pertronix ring, the car is running 100%. I will let you know if something changes with the warmer weather but so far, so good!

 

[richie]

Sorry to bring this thread up back to the top myself, but I thought it would be worth it for the archives.... It's been months since I reduced the sitting height of the rotor and the problem is completely gone!