85 Running Hot
Thread Starter
8th Gear
Joined: Nov 2001
Posts: 8
Likes: 0
From: Larkspur CO
85 Running Hot
My 85 is starting to run hot as the weather get hotter. The temp will sometimes get up to about 250 degrees and then quickly drop back down to about 220 and then climb back up and then drop again. I put a new thermostat in about 1.5 years ago.
Does this sound like a bad thermostat or bad ECM or something else?
Thanks!
Does this sound like a bad thermostat or bad ECM or something else?
Thanks!
Team Owner
Joined: Sep 2001
Posts: 62,143
Likes: 1,729
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Re: 85 Running Hot (dlsmith)
Well its designed to run rather hot. But there may be a problem if its getting up to 250.
First thing, clean the front of your radiator. In between the rad and the condensor, there will be a ton of trash. Just removing that will lower temps 10-15F if its really clogged. Flush and refill the radiator.
The main fan comes on at 228F, I would make sure its doing so, and then buy a fan switch from Ecklers or MidAmerica and wire that to the main fan so that it will come on sooner. The only other way is to get someone here to reprogram the chip's fan settings.
I would at least change the thermostat to a 180, I run a 160 in my 86. Whether you use 160 or 180 depends on how much you drive her in winter. I run mine in winter quite a bit, but winters here are rather mild. The stock stat is 195, which i think is too high. Just from installing a lower temp stat, the average running temperature should drop 10F. Mine dropped a little more because of the 160. I'm sure someone else will chime in and say that the 195 is the only one you should run, I leave it up to you to decide.
First thing, clean the front of your radiator. In between the rad and the condensor, there will be a ton of trash. Just removing that will lower temps 10-15F if its really clogged. Flush and refill the radiator.
The main fan comes on at 228F, I would make sure its doing so, and then buy a fan switch from Ecklers or MidAmerica and wire that to the main fan so that it will come on sooner. The only other way is to get someone here to reprogram the chip's fan settings.
I would at least change the thermostat to a 180, I run a 160 in my 86. Whether you use 160 or 180 depends on how much you drive her in winter. I run mine in winter quite a bit, but winters here are rather mild. The stock stat is 195, which i think is too high. Just from installing a lower temp stat, the average running temperature should drop 10F. Mine dropped a little more because of the 160. I'm sure someone else will chime in and say that the 195 is the only one you should run, I leave it up to you to decide.
Le Mans Master
Joined: Jul 2002
Posts: 5,818
Likes: 2
From: Alive and well in Burlington NC
Re: 85 Running Hot (vader86)
:iagree: with Vader. I run a 160 and a used Ed Wright chip (thanks 91 project) to turn the fans on earlier. I don't see much over 185. Of course the first steps would be to flush the rad and clean out the trash and see where you are.
