Motor rebuilt for the second time ..............New AOD is in and working great.
Trying to break this thing in & now I am having problems with my ignition.

I have had a Pertronix in it for a few years now & it has always worked great.

My issue is...when the motor gets to operating temp....it cuts out under load.
It isnt a fuel issue.

I have replaced the coil...checked all the grounds....the guy who put my motor in even got me a new Pertronix because he thinks they had yanked one of the wires on the sending unit....causing it to rub against the distibutor cam.

I replaced that today & still it spits & sputters under load.
It is starting to pi#@ me off.
As I cant seem to stop spending money on it lately......I havent been able to drive it down the block without another money eating issue arising.

 

Check your timing, also make sure the plug wires are in the correct firing order. That will cause it to idle ok, but spit and backfire. Does it start ok? or seem to bind as it starts? Start with the basics... Bring it up to #1 on the damper and see where the rotor points to. Also, did you put a new chain and gears in? Did you get the 2 dimples to line up correctly? If they're off, the timing will be off. It sounds like a timing issue to me.

Barry

 

Pull the vac adv line from the carb or manifold and suck on it..does it correctly ?sounds like that to me or vacuum related. But alas your the one with the hands on status. Also mine did something similar with the Xri module from Crane.. it was bound at the entry hole on the dizzy enough to hinder the vac advance working correctly. It would pop out the pipe like a shotgun..I was reving the engine by hand an noticed the the wire going in stop moving when it would cut out or pop. Removed the cap and pushed wire through coiled it around the rotor so there was plent slack and no kinks. Runs like a champ now.

 

We have the firing order correct as it was running fine after putting the tranny in.
I actually drove it with the old C6 for a few weeks without incident.

Then we put the AOD in it & about 3 days later it started misbehaving.
(Makes me think we have pulled a wire OR stressed a wire from the cab to the motor.)
It only occurs after the motor gets to a proper operating temp & you have driven it a few miles.....It then stutters under a medium load.....NEVER sitting still. (keeps pointing at an electrical issue..stressed wire?...hmmm...)

We found the worn wire on the Pertronix sending unit from rubbing on the rotor & replaced that & put a flamethrower coil in it.

I havent checked the vacuum but that is a great idea. (That would be such a coincidence if it was the vacuum hose......but I will definitely check.)


I had to jack the cab off the frame to get my AOD in as we had already had the motor in. (That is why I am suspecting a stressed wire.)......

It is just very frustrating as this is my daily driver.......good thing thing I live in Sunny SoCal.........
I will just HAVE to ride my Thruxton while figuring this out.

 

It is not vacuum as I am pulling a good vacuum from the base of the carb.

One odd thing is, at idle when I turn my heater on the truck dies.

oops. I think jacking the cab up caused a couple problems.
If it isnt one thing.......it is another.

 

O.K....after searching around I found the fuse was blown for the Heater.
The Positive wire to the heater was also damaged.

A little more investigation revealed the Neutral safety switch wire (pos) from my Lokar had fused with the wire connecting to my heater. (Both most likely due to the cab being moved.)
It was causing a voltage drop on my electrical system which would kill the motor under load.

Rewired all of these.......no issues so far after a 30 mile drive.
Thanks for responding.
I dont use this site alot...but when I do I am usually pleased with the results.
Plus it gives me a place to vent when Gremlins rear their ugly heads.


I will give an update on my new Dominator Jr. AOD tranny after I put some more miles on it.