how hot can the ECM get?

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AwesomeJ10
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how hot can the ECM get?

Post by AwesomeJ10 »

I am swapping in a 7747 ECM into my dually. I REALLY don't want to cut the FW as it's in really good shape and I'm swapping in the vortec 8.1 here in a few months which has a PCM designed for the engine compartment.

I am thinking about putting the ECM into the engine compartment. Will it last 3-4 months? The underhood engine temps are pretty cool.

thoughts?

FSJ Guy
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Re: how hot can the ECM get?

Post by FSJ Guy »

I have heard that they're not supposed to be baked in a paint booth oven, but that was a while ago. If you put it away from the exhaust manifolds and protect it from water and excessive vibration, I suspect it'll be fine for short term. Just carry an extra with the swapped EPROM for quick swaps.

Maybe put it in an ammo box with a CPU fan and filter for good measure?
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Re: how hot can the ECM get?

Post by AwesomeJ10 »

I have two modded 7747's with a ZIF/sf5112 chip. I also have another 7747 that came from a 88 or 89 with a V8.

Planning to drive the truck ~2000 miles next week, so we will see....

will e
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Re: how hot can the ECM get?

Post by will e »

Never thought of that. My Jeeps control module for fuel delivery sits right on top of the engine. ;)

Can you place ecm behind the grill somewhere?
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Re: how hot can the ECM get?

Post by AwesomeJ10 »

will e wrote:Never thought of that. My Jeeps control module for fuel delivery sits right on top of the engine. ;)

Can you place ecm behind the grill somewhere?
haha

but does it actually run? :fsj:
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shimniok
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Re: how hot can the ECM get?

Post by shimniok »

Automotive grade components are probably rated to 257F ***BUT*** don't run it anywhere near that hot. Electrical behavior changes with temp and you might overheat/blow the power transistors that run the injectors, etc.

So... I'd keep it < 160F and call it good. Carry a spare ecm. If it bakes, move it.

And, besides, you can always patch a hole in the firewall. :D
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Re: how hot can the ECM get?

Post by AwesomeJ10 »

So for the record....

I placed the 7747 ECM under the hood, on the fender on a big piece of foam and drove 2500 miles cross country. Outside temps as high as 98 degrees.

The ECM didn't seem to mind and worked great!
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Re: how hot can the ECM get?

Post by shimniok »

Cool! (Pun intended)

sent from my MotoX
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The world's first Robotic Full Size Jeep!

FSJ Guy
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Re: how hot can the ECM get?

Post by FSJ Guy »

Nice to hear! I wonder if the lack of weatherproofing was more of an issue as to why GM put them inside.

In their stock location there is NO airflow and there are a few heatsinks inside.
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Re: how hot can the ECM get?

Post by AwesomeJ10 »

FSJ Guy wrote:Nice to hear! I wonder if the lack of weatherproofing was more of an issue as to why GM put them inside.

In their stock location there is NO airflow and there are a few heatsinks inside.
Good point.
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