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Replacing ICM --- Which Compound?? by Notorio
Started on: 04-02-2015 08:43 PM
Replies: 14 (1651 views)
Last post by: css9450 on 04-03-2015 11:59 AM
Notorio
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Report this Post04-02-2015 08:43 PM Click Here to See the Profile for NotorioSend a Private Message to NotorioEdit/Delete MessageReply w/QuoteDirect Link to This Post
Just got a new ICM from O'Reilly's ... $40 and Made in USA by BWD Automotive (i.e. Borg Warner and someone else). First electronic part I have gotten in ages that was NOT made in China!!

Instructions say to apply a 'liberal coating of enclosed dimethylpolysiloxane compound to the module's metal mounting plate to prevent damaging heat build up.' This looks like your average PDMS paste, clear, nothing else added. I have always heard one should apply 'heat sink compound' (usually a white particulate paste). Theoretically, it would seem that the heat conducted up through the distributor should be insulated from the ICM, not conducted to it by a good thermal transfer medium like heat sink compound. What say you?

John
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Spoon
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Report this Post04-02-2015 08:57 PM Click Here to See the Profile for SpoonSend a Private Message to SpoonEdit/Delete MessageReply w/QuoteDirect Link to This Post
This might help..

https://www.fiero.nl/cgi-bin...0763&style=printable

Spoon

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Gall757
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Report this Post04-02-2015 09:09 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
1. ALWAYS use heat-sink compound, which is NEVER clear....some ICMs are sold with clear di-electric grease, which is the wrong stuff. Heat sink compound can be found at computer stores. It is usually white and sometimes silver.....the paste is transferring heat from the ICM to the metal plate below.

2. BWD automotive is not connected with Borg Warner....but a brand of Standard Motor Products...An auto parts supplier in New York. If they supplied di-electric grease (or PDMS) with their ICM, I would wonder if they knew what they are doing....

3. Make sure to use clean screws that fit right when you install your new ICM.....they are the ground for the module.

[This message has been edited by Gall757 (edited 04-02-2015).]

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Patrick
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Report this Post04-02-2015 09:40 PM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Notorio:

Theoretically, it would seem that the heat conducted up through the distributor should be insulated from the ICM, not conducted to it by a good thermal transfer medium like heat sink compound. What say you?


I say you've got it completely backwards if you believe "the heat conducted up through the distributor" is hotter than the ICM.
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fierofool
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Report this Post04-02-2015 09:55 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
 
quote
Originally posted by Patrick:

I say you've got it completely backwards if you believe "the heat conducted up through the distributor" is hotter than the ICM.


Correct-o! There is a lot of heat generated inside the distributor and not much air movement. There is more air moving outside and around the distributor to keep the base cool and draw the heat from inside. Even though there are small round vents on the bottom of the distributor, I believe they do little in helping air to flow through the inside because there's no mechanism inside to pump the air. Radio Shack has a good white heat sink grease and some folks here use the silver compound.

BWD might make some parts in the USA, but most are made outside the US and packaged in the BWD box. Sorenson and Welles do the same thing.
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Notorio
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Report this Post04-03-2015 12:06 AM Click Here to See the Profile for NotorioSend a Private Message to NotorioEdit/Delete MessageReply w/QuoteDirect Link to This Post
Hmmmn, I am not convinced. Let's see what we've got here:

#1. BWD doesn't know what they are doing b/c they didn't enclose 'heat sink compound.' I've worked with a lot of Electrical Engineers over the years and they seem to be pretty clued in. Could they be making this large of a mistake? Perhaps I should try to call/email them tomorrow and see if I can get a definitive answer. (Yes, I believe in miracles.)

#2. ICM is hotter than the distributor base. OK, this does seem reasonable, given all the electrical switching that it is doing. But isn't that at low voltage? I was not able to find any data on line to indicate the typical temperatures of either of these components. Anyone out there ever measured these (or can now) with a thermocouple? I guess after replacing this tomorrow I can warm the engine up to operating temp and then do a 'finger test' (Yes, with the engine OFF.)

John
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theogre
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Report this Post04-03-2015 12:38 AM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreEdit/Delete MessageReply w/QuoteDirect Link to This Post
many come w/ plane "dielectric"/"silicon" grease. Is cheap but does work ok to remove heat.

Any Heatsink grease are much better to remove heat.
Most White compound 3-4 times better then plane silicon, ~20 times or more better then nothing to fill in the gaps.
RS has white compound RS wants $6 for ~0.5oz but RS is gone or will be soon in most places.
Home Depot has 3oz tube for $8.88 only online
others google: heat sink compound

If you have extra CPU silver etc greases fine but don't bother buying it. ICM will need 2x more then most CPU.
Many "silver" products are aluminum power, not silver. Often They cost allot more but shows little for that money for most uses.

Yes! Make Sure screws are clean etc. Screw(s) are only ground for HEI ICM. IF you have black oxide screws then replace them.
"Ground" wire is Not a "real" ground. See my Cave, Ground "Myth" notes
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Patrick
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Report this Post04-03-2015 01:32 AM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Notorio:

Hmmmn, I am not convinced.

That's your problem.

 
quote
Originally posted by Notorio:

#1. BWD doesn't know what they are doing b/c they didn't enclose 'heat sink compound.' I've worked with a lot of Electrical Engineers over the years and they seem to be pretty clued in. Could they be making this large of a mistake?


It doesn't matter how "clued in" the engineers are, it's the bean counters who run the show. Dielectric grease is cheaper than the proper heat sink compound. Most customers don't know the difference (or care), and when the ICM burns out shortly thereafter... voila, another sale to be made!

 
quote
Originally posted by Notorio:

#2. ICM is hotter than the distributor base. OK, this does seem reasonable, given all the electrical switching that it is doing. But isn't that at low voltage? I was not able to find any data on line to indicate the typical temperatures of either of these components. Anyone out there ever measured these (or can now) with a thermocouple? I guess after replacing this tomorrow I can warm the engine up to operating temp and then do a 'finger test' (Yes, with the engine OFF.)


It was discussed here - Installed heat sink on distributor under ignition module

But by all means... do the finger test! See if you can somehow hold the ICM while the engine's running. Report back how long you held onto the ICM before frostbite set in. Curious minds will want to know.
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mitchjl22
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Report this Post04-03-2015 04:28 AM Click Here to See the Profile for mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post
Thermal Paste or Thermal compound is what is on the side of the ones we sell at bestbuy.

http://www.bestbuy.com/site...478854&skuId=9609458

Oh yeah and watch this.
https://youtu.be/N038D6DbHQ8

[This message has been edited by mitchjl22 (edited 04-03-2015).]

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Patrick
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Report this Post04-03-2015 04:47 AM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by mitchjl22:

Oh yeah and watch this.
https://youtu.be/N038D6DbHQ8


OMG... It took the guy five minutes and thirty seconds to state one minute's worth of info. But yeah, he's correct.

[This message has been edited by Patrick (edited 04-03-2015).]

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Gall757
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Report this Post04-03-2015 10:14 AM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
The ICM is the most replaced part on the Fiero V6 by far. Many of them fail within days of being installed. This forum evaluates for the consumer, with a fairly large sample size, where the parts companies evaluate for the parts companies. It used to be that whatever was good for GM, was good for the country....but I think we can lay that one to rest. They don't always have your best interests at heart. The OEM suppliers are in tougher shape, trying to provide something good while being hammered on price by the car company buyers....I can only imagine what happens at purchase negotiations with AUTOZONE et. al. The BWD rep probably stumbled out of O'Reilly's front office saying.....'Thank you Lord...I only had to cheapen up on the goop and not the whole ICM!'

[This message has been edited by Gall757 (edited 04-03-2015).]

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Report this Post04-03-2015 10:53 AM Click Here to See the Profile for darbysanSend a Private Message to darbysanEdit/Delete MessageReply w/QuoteDirect Link to This Post
I've taken my ICM to Autozone to have it tested many times. I have them run the test at least 3 times, so that heat builds up ( they usually fail under a heat load). When they hand them back to me, even when they are good, they are too hot to handle. Do like suggested here and use Heat Sink Compound. Your ICM will love you for it

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FIEROPHREK
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Report this Post04-03-2015 11:16 AM Click Here to See the Profile for FIEROPHREKSend a Private Message to FIEROPHREKEdit/Delete MessageReply w/QuoteDirect Link to This Post
Has anyone ever applied a small heat sink under the base of their distributor? I was thinking of doing this to help shed heat from the underside of the dizzy.

Kind of like these:


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[This message has been edited by FIEROPHREK (edited 04-03-2015).]

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fierosound
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Report this Post04-03-2015 11:58 AM Click Here to See the Profile for fierosoundClick Here to visit fierosound's HomePageSend a Private Message to fierosoundEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by FIEROPHREK:

Has anyone ever applied a small heat sink under the base of their distributor?



Yup. https://www.fiero.nl/forum/A...110502-2-095917.html
It probably also helps to have the trunk blower system blowing air at the distributor area.


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css9450
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Report this Post04-03-2015 11:59 AM Click Here to See the Profile for css9450Send a Private Message to css9450Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by FIEROPHREK:

Has anyone ever applied a small heat sink under the base of their distributor? I was thinking of doing this to help shed heat from the underside of the dizzy.



Absolutely! Patrick posted the link just a few posts above.

EDIT: And Fierosound!

[This message has been edited by css9450 (edited 04-03-2015).]

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