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To thermal paste or not by fierofool
Started on: 08-19-2024 02:41 PM
Replies: 11 (233 views)
Last post by: Dennis LaGrua on 08-28-2024 07:19 PM
fierofool
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Report this Post08-19-2024 02:41 PM Click Here to See the Profile for fierofoolClick Here to visit fierofool's HomePageSend a Private Message to fierofoolEdit/Delete MessageReply w/QuoteDirect Link to This Post
For those who are running DIS ignition systems, whether stock to your engine, or a conversion like the 7730, do you use thermal paste (heat sink grease) on the ignition control module?

I have two identical coil pack units with modules, one from a Beretta and the other from a Camaro. neither have thermal paste on them. Was this normal from the factory or just oversight on the vehicle owner's part? Does your 3800 conversion module have thermal paste?

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Dennis LaGrua
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Report this Post08-20-2024 03:11 AM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
For the large DIS ignition module that sits under the three ignition coils, thermal grease is not used. The module must have a solid ground connection to a clean mounting plate. Also the mounting plate MUST have a solid ground. There should be a ground strap there.
For the Fiero ignition module that is in the distributor; that must use thermal grease under it as well as the module in the 4.9L swaps.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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cartercarbaficionado
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Report this Post08-20-2024 05:19 AM Click Here to See the Profile for cartercarbaficionadoSend a Private Message to cartercarbaficionadoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by fierofool:

For those who are running DIS ignition systems, whether stock to your engine, or a conversion like the 7730, do you use thermal paste (heat sink grease) on the ignition control module?

I have two identical coil pack units with modules, one from a Beretta and the other from a Camaro. neither have thermal paste on them. Was this normal from the factory or just oversight on the vehicle owner's part? Does your 3800 conversion module have thermal paste?


no thermal grease on any of them. you could use it but I would say use dialetric grease instead of thermal paste since its a lot easier to clean up and is very unlikely to contain bits of metal or gallium

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Dennis LaGrua
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Report this Post08-20-2024 10:34 AM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by cartercarbaficionado:

no thermal grease on any of them. you could use it but I would say use dialetric grease instead of thermal paste since its a lot easier to clean up and is very unlikely to contain bits of metal or gallium


Dielectric grease is electrical insulation. The DIS module gets a ground connection from the mounting plate. The plate and the module must be kept clean. Only the small inside distributors ignition modules need thermal grease on the underside.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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cartercarbaficionado
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Report this Post08-20-2024 10:46 AM Click Here to See the Profile for cartercarbaficionadoSend a Private Message to cartercarbaficionadoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:


Dielectric grease is electrical insulation. The DIS module gets a ground connection from the mounting plate. The plate and the module must be kept clean. Only the small inside distributors ignition modules need thermal grease on the underside.


correct you are. most of the gm coils I deal with actually ground through the screws themselves into the plate instead of the epoxy bottom (only had a set of performance ones with metal cooling plates on the bottom from zzp but they are garbage) lq1 and 3800s get very weird compared to early gms.
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1985 Fiero GT
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Report this Post08-20-2024 02:04 PM Click Here to See the Profile for 1985 Fiero GTSend a Private Message to 1985 Fiero GTEdit/Delete MessageReply w/QuoteDirect Link to This Post
Somewhat unrelated, but where is the ogre? He hasn't posted in well over a week that I can tell, he would normally jump right into a thread like this.
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Report this Post08-20-2024 02:58 PM Click Here to See the Profile for Yellow-88Send a Private Message to Yellow-88Edit/Delete MessageReply w/QuoteDirect Link to This Post
Dielectric grease is not the same as thermal compound or heat sink compound. That's a compound with very high thermal conductivity. The idea is to eliminate any refraction between the two metal surfaces. It's use is to help move heat from the ICM to the base of the distributer were it is radiated to the air. That's not easy to do given the temperature where is is located. Be aware that crap on the underside of the distributer base is insulation keeping heat from moving. As far as I know, the screws are the ground path.

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Dennis LaGrua
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Report this Post08-20-2024 03:56 PM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Yellow-88:

Dielectric grease is not the same as thermal compound or heat sink compound. That's a compound with very high thermal conductivity. The idea is to eliminate any refraction between the two metal surfaces. It's use is to help move heat from the ICM to the base of the distributer were it is radiated to the air. That's not easy to do given the temperature where is is located. Be aware that crap on the underside of the distributor base is insulation keeping heat from moving. As far as I know, the screws are the ground path.

All true statement on the 2.8L and its good to explain the difference. Its just not applicable as this post was about the 3800SC DEI coil pack module for which no compound is required. You just install that ICM clean and torque the coils down w a 5.5mm socket,.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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fierofool
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Report this Post08-20-2024 04:31 PM Click Here to See the Profile for fierofoolClick Here to visit fierofool's HomePageSend a Private Message to fierofoolEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thank you all. Dennis, this is actually for a 3.4 with 7730 conversion but same principles as the 3800. I'm not sure, but they may even use the same ICM.

I have been running a module with heat sink compound on it for 3 or 4 years. It gave up last Saturday. Unfortunately, I didn't have my spare with me and required a 25 mile tow home. No towing insurance. When I removed the spare coil pack and module from my cabinet, I find that it also had thermal paste on it. I don't know if it came from the Beretta or the Camaro, as I acquired both maybe 8 or 10 years ago when I first began preparing for the 7730 conversion.

So, I installed it with a slight smear of compound. Guess I'll need to remove it.
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Dennis LaGrua
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Report this Post08-21-2024 10:04 AM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by fierofool:

Thank you all. Dennis, this is actually for a 3.4 with 7730 conversion but same principles as the 3800. I'm not sure, but they may even use the same ICM.

I have been running a module with heat sink compound on it for 3 or 4 years. It gave up last Saturday. Unfortunately, I didn't have my spare with me and required a 25 mile tow home. No towing insurance. When I removed the spare coil pack and module from my cabinet, I find that it also had thermal paste on it. I don't know if it came from the Beretta or the Camaro, as I acquired both maybe 8 or 10 years ago when I first began preparing for the 7730 conversion.

So, I installed it with a slight smear of compound. Guess I'll need to remove it.


In reviewing all of the repair manuals concerning replacing DIS coil pack modules; we could not find any reference to using thermal or dielectric grease under it. This is contrary to what is recommended for the small distributor mounted modules. When I once removed a module from a new 3800SC engine back in the day, , the mounting plate was clean. We found that when exposed to weather over time the mounting plate exhibits corrosion and then a miss sets in. Then a cleaning is in order. I know of several other folks that experienced misfires due to this corrosion. The fix was simply cleaning with a soft wire brush. Also found that its very important to have a solid ground connection to the mounting plate. This is critical. There is often a ground strap there.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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fierofool
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Report this Post08-21-2024 11:43 AM Click Here to See the Profile for fierofoolClick Here to visit fierofool's HomePageSend a Private Message to fierofoolEdit/Delete MessageReply w/QuoteDirect Link to This Post
Neither of the assemblies had ground straps when I removed them from the original engines. Of course, each had a factory mount securely bolted to the engine that would suffice for a ground. My current setup is mounted where the coil and distributor of the 2.8 would be located. A solid base bolted to the engine. The assembly also sits directly in front of the cooling tube that was stock on the 87 V6's. Just as an extra element of security, I'm planning to add a braided ground strap.
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Dennis LaGrua
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Report this Post08-28-2024 07:19 PM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by fierofool:

Neither of the assemblies had ground straps when I removed them from the original engines. Of course, each had a factory mount securely bolted to the engine that would suffice for a ground. My current setup is mounted where the coil and distributor of the 2.8 would be located. A solid base bolted to the engine. The assembly also sits directly in front of the cooling tube that was stock on the 87 V6's. Just as an extra element of security, I'm planning to add a braided ground strap.


My 3800SC engine is a series III and stock, it came with a ground strap from the block to the coilpack mounting bracket. GM may have added the strap on the 04-08 3800 engines.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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