Jump to content
Forums Gone... but not forgotten!
Pontiac of the Month

Steve Morris' 1967 GTO

2021 April
of the Month

  • Welcome!

    Welcome to Forever Pontiac, where we keep the memory of Pontiac alive with great discussion, maintenance tips, restoration/modification progression "blogs" and help from professional & DIY mechanics. Also, wonderful competitions that occur regularly. Please register for an absolutely free account to join in!

Recommended Posts

I have 1965 GTO, the motor is a 1969 400, it has an after market HEI Distributor. The car was running fine. Over the last few months I installed an vintage air system. some gages under the dash and a few other goodies, like aluminum pulleys. Got it ready to start the car started but wouldn't run, got to the point were it wouldn't even try to start,  checked things out found had no spark.  Ordered a new MSD cap, rotor, and ignition module.  Put it in and again it tried to start put wouldn't stay running, then again I lost spark.  Not wanting to wait for another MSD module I went to O Reilly's and bought a Accel Ignition module. Put it in it started right up, ran fine.  Went out Today after setting for about a week tried to start it NO SPARK.   I really hate electrical problems.  Any one got ant ideas as to what the problem could be

Link to post
Share on other sites

Tired of these Ads? Register Today!

Here is a pretty good HEI diagnosis article that might help.

https://www.chevyhardcore.com/news/hei-distributor-troubleshooting-with-performance-distributors/

 

Here is YouTube video on the same subject.

 

 

Edited by Frosty
Link to post
Share on other sites

Thanks that Video pretty basic, I know to check all of what he is showing. My problem is more complicated than that. I all ready have all new parts. But something is burning out the ignition modules, Need to find out what 

Link to post
Share on other sites

Like you Neal, I also scratch my head when it comes to electrics. All I could think of was if you have some sort of fusible link or circuit breaker that's either blowing or tripping? Is the ignition module internally fused? Any sort of rust, dirt or compromised surface on any connection will create resistance that can lead to all sorts of problems. Someone recently posted that where the distributor base abuts the block, that's actually an earth. Is that all good?

I'm a bit of a sook. I'll have a go trying to fix something but if it keeps beating me, I don't keep smashing my head against the wall - I take it to a professional!

  • Like 1
Link to post
Share on other sites

This may sound crazy....Are all the metal ends on the spark plug wire ends pushed all the way down and tightly fit the contacts on the distributor cap and the plugs....???

It's possible for the rubber boots to be bottomed out but the wire ends not be directly contacting the plugs/distributor cap...Causing the spark to have to jump a gap between the wire ends and the plugs/distributor cap contacts...car would run OK...Because the spark would be insulated inside the rubber boot and not short against anything metal...But If the spark has to jump a gap between the wire ends and the contacts...It will cause the ignition module to internally overheat and prematurely fail...Because of the extra energy needed to jump any gaps that may be created by the wires not tightly connected to the plugs/distributor.....

  • Like 1
Link to post
Share on other sites

Most modules go bad because of heat. I will suggest some more obscure items:

1. AC voltage spikes from your alternator, try looking across the diode assembly to see if your current or voltage is spiking.

2. Possible ground issue? Although by now you probably have looked at that

3. I read on a rare occasion, as the distributor ages and wears, the bushing in the distributor shaft goes bad and starts to cause excessive heat. The heat travels up the housing to the bottom plate of the distributor and cooks the module.

4. If you HEI distributor still has a condenser, try replacing it, it maybe bad.

Edited by Frosty
Link to post
Share on other sites

Contact the manufacturer, they have prob solving tech's ready to try N help.  I switched out my Mallory duel point to their light trigger module.  $115.00 for each module. Went through them like candy.  Mallory suggested a plug in module on the outside of the distributor. (forget the name, but like a resetable fuse)  Didn't help anyways.  They ended up refunding my money for the module and sent back all the burned out light triggers which they replaced with new.  Never did anything else to the car and problem has not been a factor since.  Bad batch of light triggers???  

  • Confused 1
Link to post
Share on other sites
18 hours ago, Frosty said:

. AC voltage spikes from your alternator, try looking across the diode assembly to see if your current or voltage is spiking.

This was my thought ! check your alternator to ensure your not sending out too many volts🙄

Link to post
Share on other sites

Thanks every one. I ordered new parts, be here tomorrow. Going out of town for the weekend. wouldn't be working on it again till next week 

Link to post
Share on other sites
  • 2 weeks later...

Finally got back to working on the GTO.  It seems that I may have a bigger problem.  Put in the new module and wiring harness,  Got the car started. but it does not want to run right,  set the timing at 10 degrees. Noticed the timing is fluctuating all over the place. I know this can be caused by the timing chain being stretched. but it was running fine before.  Do you think this could be the distributer. It is an after market billet distributor I don't know who made it, it was in the car when I bought it or another reason for the timing to fluctuate, thanks

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Tired of these Ads? Purchase Enhanced Membership today to remove them!
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.