Sunday on the way home from Eureka Springs our 79 died on interstate 44 just outside St. Louis. It missed fired several times then died just like some turned off the iginition key. This is the second time in one year the iginition module shot craps. Has anyone else had this problem?

 

What brand of ignition module are you using? Are you putting the dielectric grease where it needs to be put when you make the swap?

BTW: In my case, the answer is "no".

 

To answer your questions I'd have to answer I don't know. The first one failed on our trip to Vettes on the rockies last year. The distributor was in the car when we bought it and the guy that worked on said it looked like an Accel unit (it has no markings). We bought a rebuilt NAPA unit to slip in which is the one that failed on Sunday, 14 months after the first one. But the car had only been driven back from Colorado and a few short jaunts around town before the trip to Eureka Springs this year. I guess I'll do some checking on whose module to buy and rebuild the old unit and keep it around as a drop in spare. I have never had a iginition module fail before in any car so if anyone has any expirence in this area I'd love to hear it.

 

I should have said this before: Buy an AC Delco module. Buy two -- keep one as a spare. Some people believe aftermarket modules are prone to failure than AC Delco units.

What are you rebuilding? The entire distributor? I've never heard of a rebuilt ignition module, nor would I want one. New ones are cheap enough...

 

They will tend to fail over a period of time but this is usually many years. Two things cause the module to fail early and these are:

No dielectric grease was used to conduct heat from the module to the distributor

The rotor not only conducts energy to the plug wires but it also shields the module from errant sparks. The rotor will begin to fail and some sparks will travel through it to the advance weights and to the module underneath. Signs of what looks like rust (orange particles) on the advance weights mechanism is a sure sign of this occuring.

A couple of comments from my own experience:

I've never had a module fail completely. They tend to fail by running rough or causing a severe bog from part to full throttle when then reach engine temp after a start.

The only time the distirbutor failed completely is when the pickup under the advance weights failed. When this goes the car will not run. Since it goes arond the distributor shaft and is below the advance weights you have to pull the distibutor, tap out the gear pin and slide the center shaft out of the distributor. When putting back together you just have to make sure the new pickup is adjusted to center so none of the teeth hit the ones on the shaft (keep an even air gap all around).

So I do the following:

Always replace the rotor every 12 months and you must use a good quality part or they will fail sooner. The HEI high voltage stresses this part.

I always have a spare module and rotor in the rear storage compartment.

For long trips I have been known to throw a spare distibutor in the back. This applies to the vette and my old IH Scout with a 350 chevy conversion.

Tools to carry are flat blade for distributor cap, phillips for rotor screws, change module screws to phillips if they are torx (saves on extra tool).

You can also carry a spare pickup module if you carry a drift to knock out the gear pin, a small hammer (does take much to knock out pin) and 9/16 wrench for distributor hold down.

The above will always get you bcak on the road no mater where you are.

Dave

 

also look at the wire's that connect to the module

 

A corection in terms Yes I will install a new module. Is anyone aware of one being better than another? More heat resistant or better quality? I will go with the Delco unit unless someone has good input.

 

Dave L82 ...so i guess you are saying that after i do the upgrade kit on the HEI i should keep all the old parts in the car???

 

If the old parts are suspect I'd throw them away and buy a spare module and pickup coil module (one with the trigger teeth around the dist shaft).

Dave

 

Not enough of the supplied grease, or not cleaning all of the old grease off before applying new will cause premature failure everytime reguardless of whose brand module you use. The grease acts as a heat sink for the module. Too much heat=cooked electronics.