I've found that to be a problem with some of the cheaper aftermarket modules, especially if you're running a lot of initial advance, if i'm not mistaken it's the white wire that performs this function.

 

I will get several battery readings before, after even during. The truck is factory stock so it has a factory modual.

 

Here are the battery measurements taken with a Fluke DVM

Before- 13.03
During crank- 10.00
After crank- 13.0
Running- 14.7 idle to 15.7 charging

 

what i was asking was if the duraspark box was a ford oem box or an aftermarket stock replacement from autozone or orielly or some place like that not like an msd.

 

As far as I know it is the original Ford OEM modual. Ann has owned it since 81 and doesn't remember anyone changing it.

 

How about the starter? Not much else left here..........

 

Hey 49, I've run into this problem before and found different answers. First off you need to make sure you have a good ground from the battery to motor, motor to body and battery to body. After you check that i would check the timing chain, stretch over time it gets worse. I would also check the starter draw when its dragging only after you make sure your grounds are good. If all that checks out replace the starter with a late model starter from a 460 gear reduction much easier on the starter system. Hope this helps chuck

 

Chuck

I have checked and added grounds to everything. Moved the direct ground to the starter bolt. I don't feel there is a problem with the timing chain as mark doesn't move around and the truck runs great. The problem seems to be heat related as it never happens when the engine is cold only after good and warmed up. I am not famillar with the starter you spoke of. What year and model starter would I look for to go on my 75?

Bob

 

Hi Bob, Bob you won't see the timing mark bounce around all the time was just one other thing to ck with age and mileage. That starter # which i get from a carquest store is 3226n it is off a 1995 Ford E350 w/460 automatic this starter is smaller and way more powerful than the old style and direct bolt in. That should solve your starter problems if everything else is right. Hope this helps, Chuck

 

Chuck

Thanks for the info. I will give it a try.

Bob