85 cooling fan runs continously
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Pro
Joined: Oct 2005
Posts: 541
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From: Freeport FL
85 cooling fan runs continously
After adjusting my valves about 5 times....now I have noticed that for some reason the coolong fan is running anytime the engine is running. Not with key on/engine stopped, but only with engine running. Possibility that I cut or broke something while taking the valve covers in and out? Location of fan relay and test procedures?
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
My 85 did this when the pasenger side head coolant sensor wire got melted and grounded on the block,
this sensor is for tte auxillary fan in front of the radiator
do you have 2 fans or one?
this sensor is for tte auxillary fan in front of the radiator
do you have 2 fans or one?
Thread Starter
Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
Yes, that is exactly what the problem was...
I only have the main fan (PO added a aux fan, but it was a bubba job so I just took it out). However, IIRC in my application this second switch will turn on the main fan, should the computer for some reason not turn it on at 180* (or whatever temp, I dont have a stock chip or stock motor, mine turns on at 180*). This sounds almost stupidly redundant, but I did a lot of research on the subject when I first got the car and was pondering the bubba job.
The wire to this secondary switch has been broken and and I never bothered to fix it, because of its redundant nature. I just had it tied up...until of course I knocked it loose putting the valve covers in and out.
I only have the main fan (PO added a aux fan, but it was a bubba job so I just took it out). However, IIRC in my application this second switch will turn on the main fan, should the computer for some reason not turn it on at 180* (or whatever temp, I dont have a stock chip or stock motor, mine turns on at 180*). This sounds almost stupidly redundant, but I did a lot of research on the subject when I first got the car and was pondering the bubba job.
The wire to this secondary switch has been broken and and I never bothered to fix it, because of its redundant nature. I just had it tied up...until of course I knocked it loose putting the valve covers in and out.
Race Director
Joined: Sep 2000
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From: The Top of Utah
You are correct on the way the fan operates on your car. It is that way, ONLY on the 1985 models, ONLY without the auxiliary fan. Later cars without the aux fan just don't have the fan switch. I would guess that while adjusting the valves, you moved that green wire that goes to the fan switch around and it has become grounded. However, if that is the case, the fan should run with the ignition "On", regardless of whether the engine is running or not. Maybe that, too, was bubba-ed (bubbaized?).
RACE ON!!!
RACE ON!!!
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
The main fan is controlled by the ECM, the front fan is controlled by the sensor that is in the passenger side head.
You could control the front fan with a "flip switch" to ground but not the front fan unless you bypass the ECM
You could control the front fan with a "flip switch" to ground but not the front fan unless you bypass the ECM
