Ongoing HEI Ignition module problem
Thread Starter
Racer
Joined: Dec 2000
Posts: 385
Likes: 0
From: Blue Ridge GA
Here are the GM part #s from the Dealer's Guide which should cover the parts you are looking for:
1986-91 Distributor /Ignition (L98)
=========================
1892261 .. TERMINAL BLOCK, (INCL CAPACITOR)
1986260 .. TERMINAL BLOCK, (TO ELEK PKG)
1977207 .. POLE PIECE AND PLATE (2 wires)
1986-91 Distributor /Ignition (L98)
=========================
1892261 .. TERMINAL BLOCK, (INCL CAPACITOR)
1986260 .. TERMINAL BLOCK, (TO ELEK PKG)
1977207 .. POLE PIECE AND PLATE (2 wires)
Unfortunately, I think the problem is with the connector from the main harness to the distributor harnesses referenced above.
Somehow, I had the image that the short harness everyone was talking about went from the end of the harness coming out of the distributor to another connection into the main harness. No such harness.
The problem area is in the connector coming from the main harness. Over the years this piece has become hard and brittle and the ears have broken off plus other issues. So, where can I get a new connector?
Thread Starter
Racer
Joined: Dec 2000
Posts: 385
Likes: 0
From: Blue Ridge GA
Possble answer to your problem is this:
1. Use ONLY the clear Di-Electric gel that comes with the module, NOT white grease , Axle Grease , or anything else , that gel takes away about one third of the heat from the Module. Heat is the biggest problems with HEI Modules.
I've been using the grease that comes with the modules.
2.Purchase only Name brand parts , I prefer Standard or AC Delco on this part , this is one part you should NEVER purchase by price only. the Walmart brand Modules to not have a good quality Circuit Board inside like the good Modules.
I tried that and the expensive name brand ones go out at the same rate as the cheapos. I've been getting the Wells units from Autozone. They replace the shot ones for free.
3.If you do need a harness of any kind , find a parts store that caries Standard Ignition parts , They will have or should have an Illustrated ignition parts book specificaly for ignition parts. Standard or Blue streak has allways had every HEI part and or harness for my repair projects.
4. BEST REPAIR/ I use and recomend the MSD HEI Module conversion kit for two reasons:
1.Replaces factory style modules with a large version made in USA by MSD , but stiil mounts inside the cap for a nice stock look.
2.The MSD module comes with the harness you need and is designed to work with their own products and extends the RPM range way past where your engine will rev. Stock modules are done by around 4500-5000 RPM anyway , their module is good to 8000 plus. Here is a listing at MSD for the whole kit , you can purchase just the Module if you want to.
check it out at:
http://www.msdignition.com/dist_82.htm
let me know how you make out...
DESERT
1. Use ONLY the clear Di-Electric gel that comes with the module, NOT white grease , Axle Grease , or anything else , that gel takes away about one third of the heat from the Module. Heat is the biggest problems with HEI Modules.
I've been using the grease that comes with the modules.
2.Purchase only Name brand parts , I prefer Standard or AC Delco on this part , this is one part you should NEVER purchase by price only. the Walmart brand Modules to not have a good quality Circuit Board inside like the good Modules.
I tried that and the expensive name brand ones go out at the same rate as the cheapos. I've been getting the Wells units from Autozone. They replace the shot ones for free.
3.If you do need a harness of any kind , find a parts store that caries Standard Ignition parts , They will have or should have an Illustrated ignition parts book specificaly for ignition parts. Standard or Blue streak has allways had every HEI part and or harness for my repair projects.
4. BEST REPAIR/ I use and recomend the MSD HEI Module conversion kit for two reasons:
1.Replaces factory style modules with a large version made in USA by MSD , but stiil mounts inside the cap for a nice stock look.
2.The MSD module comes with the harness you need and is designed to work with their own products and extends the RPM range way past where your engine will rev. Stock modules are done by around 4500-5000 RPM anyway , their module is good to 8000 plus. Here is a listing at MSD for the whole kit , you can purchase just the Module if you want to.
check it out at:
http://www.msdignition.com/dist_82.htm
let me know how you make out...
DESERT
Racer
Joined: Sep 2005
Posts: 271
Likes: 0
From: New Freedom PA
Stealthvette I feel your pain
Ok,
Have you tried checking the charging voltage at the distributor , it should not be over 14.5 anywhere in the electrical system , if its too low or higher it can be hard on ignition parts.
Also if you suspect a wiring problem (which I do) based on your description , you will need to obtain an ohmeter and a factory wiring diagram manual. once you have the wiring manual you will have to check everywire in the disrtibutor harness back into the car for a possible intermitent short to ground. it will be a very long process.
If you are the original owner of your Vette chances are no one has hacked up the wiring harness , If your not , the first thing ALWAYS look for is ELECRTICAL TAPE! its a sure sign someone has been in there HACKING or trying to splice something. even probing with a testlight can leave hole in wiring , under the hood that will de-grade wiring internally and over time cause high resistance or a short circuit
Warning this is the type off Diagnosis and Repair that will require alot of patience on your part , if you don't think you are upto the task , take it to someone who does wiring work. But be prepared for alot of $$$$$'s spent. Most shop's will charge time and material which can get very expensive quickly. Good Luck...
Desert
Have you tried checking the charging voltage at the distributor , it should not be over 14.5 anywhere in the electrical system , if its too low or higher it can be hard on ignition parts.
Also if you suspect a wiring problem (which I do) based on your description , you will need to obtain an ohmeter and a factory wiring diagram manual. once you have the wiring manual you will have to check everywire in the disrtibutor harness back into the car for a possible intermitent short to ground. it will be a very long process.
If you are the original owner of your Vette chances are no one has hacked up the wiring harness , If your not , the first thing ALWAYS look for is ELECRTICAL TAPE! its a sure sign someone has been in there HACKING or trying to splice something. even probing with a testlight can leave hole in wiring , under the hood that will de-grade wiring internally and over time cause high resistance or a short circuit
Warning this is the type off Diagnosis and Repair that will require alot of patience on your part , if you don't think you are upto the task , take it to someone who does wiring work. But be prepared for alot of $$$$$'s spent. Most shop's will charge time and material which can get very expensive quickly. Good Luck...
Desert
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
harness
I sympathize with you. I have a 383 TPI that is sitting on my run stand, and I am trying to get an 89 harness to conform into a package to slide into my 57 chevy pickup.
The harness goes through a firewall connector that is filled with a heat sensitive goo that remelts, every time you run your car and get it hot, and conforms to the wires in that connector cavity.
I hair-dryered the gooo off the wires, and it looks pretty bad in that 4 inch area. But I have the exact wiring you are trying to fix in my hand when I am working with the harness. The distributor connector I was told can be obtained at a car quest, but I haven't got far enough along to start changing out all the bad connectors yet.
but I know exactly what you are talking about.
If you get the connector, the connector in the distributor is difficult to work with because it is extremely brittle and the one I have cracked into little pieces. I used silicone sealer to make a pseudo-connector for the distributor, and trimmed it with a razor blade.
It fits, but is pretty flexible.
Basically,my run stand is a frame with no car around it. so it's easy to set it up and run any small block chevy. So when problems like this come up, it's easy to mess with.
Chris
The harness goes through a firewall connector that is filled with a heat sensitive goo that remelts, every time you run your car and get it hot, and conforms to the wires in that connector cavity.
I hair-dryered the gooo off the wires, and it looks pretty bad in that 4 inch area. But I have the exact wiring you are trying to fix in my hand when I am working with the harness. The distributor connector I was told can be obtained at a car quest, but I haven't got far enough along to start changing out all the bad connectors yet.
but I know exactly what you are talking about.
If you get the connector, the connector in the distributor is difficult to work with because it is extremely brittle and the one I have cracked into little pieces. I used silicone sealer to make a pseudo-connector for the distributor, and trimmed it with a razor blade.
It fits, but is pretty flexible.
Basically,my run stand is a frame with no car around it. so it's easy to set it up and run any small block chevy. So when problems like this come up, it's easy to mess with.
Chris
Le Mans Master
Joined: Feb 2005
Posts: 6,457
Likes: 563
From: Clearwater Florida
Possble answer to your problem is this:
1. Use ONLY the clear Di-Electric gel that comes with the module, NOT white grease , Axle Grease , or anything else , that gel takes away about one third of the heat from the Module. Heat is the biggest problems with HEI Modules.
2.Purchase only Name brand parts , I prefer Standard or AC Delco on this part , this is one part you should NEVER purchase by price only. the Walmart brand Modules to not have a good quality Circuit Board inside like the good Modules.
3.If you do need a harness of any kind , find a parts store that caries Standard Ignition parts , They will have or should have an Illustrated ignition parts book specificaly for ignition parts. Standard or Blue streak has allways had every HEI part and or harness for my repair projects.
4. BEST REPAIR/ I use and recomend the MSD HEI Module conversion kit for two reasons:
1.Replaces factory style modules with a large version made in USA by MSD , but stiil mounts inside the cap for a nice stock look.
2.The MSD module comes with the harness you need and is designed to work with their own products and extends the RPM range way past where your engine will rev. Stock modules are done by around 4500-5000 RPM anyway , their module is good to 8000 plus. Here is a listing at MSD for the whole kit , you can purchase just the Module if you want to.
check it out at:
http://www.msdignition.com/dist_82.htm
let me know how you make out...
DESERT
1. Use ONLY the clear Di-Electric gel that comes with the module, NOT white grease , Axle Grease , or anything else , that gel takes away about one third of the heat from the Module. Heat is the biggest problems with HEI Modules.
2.Purchase only Name brand parts , I prefer Standard or AC Delco on this part , this is one part you should NEVER purchase by price only. the Walmart brand Modules to not have a good quality Circuit Board inside like the good Modules.
3.If you do need a harness of any kind , find a parts store that caries Standard Ignition parts , They will have or should have an Illustrated ignition parts book specificaly for ignition parts. Standard or Blue streak has allways had every HEI part and or harness for my repair projects.
4. BEST REPAIR/ I use and recomend the MSD HEI Module conversion kit for two reasons:
1.Replaces factory style modules with a large version made in USA by MSD , but stiil mounts inside the cap for a nice stock look.
2.The MSD module comes with the harness you need and is designed to work with their own products and extends the RPM range way past where your engine will rev. Stock modules are done by around 4500-5000 RPM anyway , their module is good to 8000 plus. Here is a listing at MSD for the whole kit , you can purchase just the Module if you want to.
check it out at:
http://www.msdignition.com/dist_82.htm
let me know how you make out...
DESERT
Thread Starter
Racer
Joined: Dec 2000
Posts: 385
Likes: 0
From: Blue Ridge GA
I sympathize with you. I have a 383 TPI that is sitting on my run stand, and I am trying to get an 89 harness to conform into a package to slide into my 57 chevy pickup.
The harness goes through a firewall connector that is filled with a heat sensitive goo that remelts, every time you run your car and get it hot, and conforms to the wires in that connector cavity.
I hair-dryered the gooo off the wires, and it looks pretty bad in that 4 inch area. But I have the exact wiring you are trying to fix in my hand when I am working with the harness. The distributor connector I was told can be obtained at a car quest, but I haven't got far enough along to start changing out all the bad connectors yet.
but I know exactly what you are talking about.
If you get the connector, the connector in the distributor is difficult to work with because it is extremely brittle and the one I have cracked into little pieces. I used silicone sealer to make a pseudo-connector for the distributor, and trimmed it with a razor blade.
It fits, but is pretty flexible.
Basically,my run stand is a frame with no car around it. so it's easy to set it up and run any small block chevy. So when problems like this come up, it's easy to mess with.
Chris
The harness goes through a firewall connector that is filled with a heat sensitive goo that remelts, every time you run your car and get it hot, and conforms to the wires in that connector cavity.
I hair-dryered the gooo off the wires, and it looks pretty bad in that 4 inch area. But I have the exact wiring you are trying to fix in my hand when I am working with the harness. The distributor connector I was told can be obtained at a car quest, but I haven't got far enough along to start changing out all the bad connectors yet.
but I know exactly what you are talking about.
If you get the connector, the connector in the distributor is difficult to work with because it is extremely brittle and the one I have cracked into little pieces. I used silicone sealer to make a pseudo-connector for the distributor, and trimmed it with a razor blade.
It fits, but is pretty flexible.
Basically,my run stand is a frame with no car around it. so it's easy to set it up and run any small block chevy. So when problems like this come up, it's easy to mess with.
Chris
I'm thinking about doing 4 individual male/female connectors to do away with the factory connectors if I can't find a replacement connector and see if that solves the problem. I DO need to check the voltage to the distributor, though. Maybe next week when work slows down to a manageble pace.
Thread Starter
Racer
Joined: Dec 2000
Posts: 385
Likes: 0
From: Blue Ridge GA
Thread Starter
Racer
Joined: Dec 2000
Posts: 385
Likes: 0
From: Blue Ridge GA
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Racer
Joined: Sep 2005
Posts: 271
Likes: 0
From: New Freedom PA
Which Distributor do you have???? ACCEL?
My 86 has eaten ignition modules about every 6 months since I've owned the car (7 years). I carry a spare and have gotten to the place I can swap them out in about 15 minutes. It's a real pain when it happens and it is raining out.
It always happens after I've driven somewhere, shut it off and then try to restart, the motor just turns over but it won't start. Swap the IM and everything is happy again.
I've tried expensive ones and cheap ones and they all go out in about 6 months. Someone on this forum told me it was the pickup coil, so I swapped out to a new Accel distributor and they still blow out. I do have an MSD 6 AL and remote coil, other than that, the ignition system is stock.
I've heard that somebody builds an IM with a circuit breaker on it. If these things work I'd like to try one. Does anyone have any experience with them?
It always happens after I've driven somewhere, shut it off and then try to restart, the motor just turns over but it won't start. Swap the IM and everything is happy again.
I've tried expensive ones and cheap ones and they all go out in about 6 months. Someone on this forum told me it was the pickup coil, so I swapped out to a new Accel distributor and they still blow out. I do have an MSD 6 AL and remote coil, other than that, the ignition system is stock.
I've heard that somebody builds an IM with a circuit breaker on it. If these things work I'd like to try one. Does anyone have any experience with them?
I assumed from your first post you had replaced the factory style distributor with an Accel HEI aftermarket type , yes the MSD four pin module set-up will NOT work with a 5 pin module set-up.
Sorry for the confusion ,Just trying to help....
DESERT
Thread Starter
Racer
Joined: Dec 2000
Posts: 385
Likes: 0
From: Blue Ridge GA
No, I still have the original style HEI although it is an Accel unit. It uses the stock type ignition module. I've supplemented the system with the MSD 6A and remote coil with the associated conversion parts.
Last edited by Stealthvette; Feb 13, 2007 at 05:14 PM.
