BesideTheBox

Tested the A/C and oil cooler fans a couple of days ago and it did not surprise me that both fans only worked at high speed. I have the new resistors and their metal heat sink disks.
Will the resistors last longer if I use thermally conductive paste?
Can anyone recommend a paste?
I'm hoping I can find something suitable locally versus online ordering. Any ideas?
I stopped at two auto parts stores and got blank stares when I explained what I wanted.
I've pulled the A/C resistor and I can see that there was some dried out white paste on the bottom of it. I measured its resistance at 266 ohms versus .5 ohms for the new resistors.

gtroth

I think heat sink compound from Radio Shack will do.

Techno Duck

Any decent PC store (have a MicroCenter nearby?) will have it.

certz

I have used Arctic Silver on CPU's. It is readily available either on the net or at your local computer store.

Slow Guy

Just curious but wouldn't this be thermally insulating compound?

BesideTheBox

Radio Shack carries Arctic Silver 5, which I believe is designed to be used between a computer's CPU and a heat sink. So it is designed to conduct heat more than insulate.

Slow Guy

OK, that makes sense. I was thinking the paste would be for insulation between the heat sink and the board itself, where you wouldn't want the heat transferred to the other board components.

I think there are components (power related) that attach to a heat sink directly where insulation would be desired.

Just a brain fart.... carry on.

Paul902

I used thermal compound and a sealing compound on mine. Thread is here

gtroth

Nice work, Paul.
If anyone were interested in a top notch professional solution, delete the heatsink compound and replace it with a cut-to-fit Sil Pad

BesideTheBox

Thank you for the recommendations.

I was all set to buy the Arctic Silver 5 at Radio Shack until I saw the price and the tiny size of the tube. Roughly $11 for a tiny tube that I wasn't sure was big enough to address both resistors. And the twin pack was $19. So I went with a twin pack of Radio Shack's silicone based heat sink material for $6 and one tube was more than enough for the two resistors.

Both resistors were replaced successfully and the relay based tests to verify both fan speeds pass now.

The bolt holding the original A/C ballast resistor in place was seized. When I tried turning it with the 4mm allen wrench, I could feel the bolt flexing. I hate that feeling. Sprayed it with WD-40 and tapped on it and let it sit for a while. Eventually, it came out without breaking. This bolt was replaced with a new stainless one. And I hope the anti-seize helps next time.

If I had to do it again, I would try the job without removing the front bumper cover. Not that removing it is hard to do, but time consuming and after getting it all back together, I think I need to make an adjustment so that it fits tighter at the junction with the front deck lid.