Hi all

I have been seeing higher than normal temps in my vert and so I gave it a run to get the temp up and I took a look. I found the fan was not running at all even well above the temp that it normally kicks on.

I didn't have time to troubleshoot it tonight ( was replacing the shocks) but I figured the first thing I'd check was for power in the wiring. Then if I got it, I'd just replace the fan motor.

So my question is to the people out there who have had their fan stop; "Was it he motor, or was it the relay that died?

I just figured I'd ask here and see if there was a 'more likely' point of failure.

[edit: sig added. I have an '86 vert]

 

Motor became open circuit due to worn out brushes. After all its a D.C. motor and brushes don't last forever. Jump 12v to the motor and see if it will run. When hot enough for the fan motor to run, measure the voltage to the motor, should be 12v and it should be able to light a 12v lamp. Or, ground the green/wh wire on the relay (87 wire colors, you don't say what year vette you have) which will force the relay to close and fan to run. You can hear the relay click, ign must be on BTW.

 

Mine was motor, which also took out the fusible link
Here are the diagnostics if you don't already have it: http://members.shaw.ca/corvette86/Co...%20Control.pdf

 

I can't get the page to show for some reason. Could you post it or email?

 

oops.
sig added to post

 

oops.
sig added to post

 

When my main fan quit working it was due to a melted connection in the connector just behind the two fusable links, luckily I had wired the booster fan to come on with the main fan so coolant temps stayed under 200deg F.

If your failed fan is due to a problem in the connector (just follow the two Orn fusable links from the battery Pos. terminal) I can give you a link to purchase a new connector set.

 

Thanks to all who answered.

Sounds like I need to check the fusable link. So where is the fusable link located on the car?

 

Right in front of battery towards relay
You can follow the big wire back from relay

 

You need adobe acrobat reader, its free at their website and many other freeware sites.

 

Well, I have a bit more info.
I unpluged the fan connector while my car was up on jacks (finnaly finishing the shocks) at a friends house. I figured I could troubleshoot it later (in my driveway) once the connector was pulled (from the bottom).
Well, on the way home it was particularly hot and the temp rose to 190 fairly quickly. However, the car did NOT start acting up like it had been doing. It had been choking and generally carrying-on every time the temp got above 180 (where the fan is set to come on).

I haven't put a tester to the connector yet, but it seems the circumstantial evidence points to a burnt motor shorting out the circuit and confusing the computer. So it looks like it will be worth my time to buy a new fan motor. - Even if the problem IS somewhere else, the car has over 170K miles, so it wouldn't hurt to replace it anyway.

I'll let you know when there is progress.


BTW: the fuseable links look good

 

Mine was the cooling fan relay in front of the battery mounted on the fender well by the master cylinder. Took it apart after installing the new one, and it was melted internally.

 

Wow.
Thanks for the info.

When you took it appart, did you have to destroy the housing? Or do you think I could take mine appart to check it out and reassemble it?

 

On mine, everything was fine but the hub on the motor shaft that holds the fan blade spun off so the motor shaft was just spinning away inside the fan blade without actually turning the blade - I had to replace the motor anyway since there was no way to get the blade off of there without cutting the motor shaft once this happened...

 

I destroyed the housing on my old one yes, as it was glued together, maybe from the factory I don't know. I cut it open with some wire cutter pliers. Looked like melted mozerella cheese only brown in color. I just went outside to the Vette right now and unplugged my new relay and removed it from the car. Once it's off the car, the housing had two snap tabs holding both halves together with no clue. It came apart easy and I was able to see the insides. Troubleshoot yours before you take it apart. If you end up having to replace it, tear it open and look inside.

Here's how to troubleshoot your inoperative fan in a nutshell. (This is for a car with one fan, might be similar with two fans.) The troubleshooting link given above is also an excellent source, but you must have Adobe Reader installed in your computer to view it as previously mentioned.

Note: By inserting a paperclip between terminals A and B of the ALDL and turning the key to the "on" position with the engine off, the fans should come on. Verity what you saw by doing this. In your case, the fans should not come on here. If that's the case, let's move on. Turn the key off.

1. Unplug the connector from the fan relay.

2. Insert a paper clip or wire between the A and B terminals of the ALDL connector (the two upper right hand ones) located above your right knee under the dash.

3. Turn the key to the "On" position with the engine not running.

4. Connect a wire between the two outer terminals of the fan relay connector.

If the fan comes on and it did not come on while the car was running hot, the relay is bad.

If the fan does not come on, it's not the relay.
Apply battery voltage directly to the fan motor. If the fan now turns on, the wiring to the fan motor has a break. Trace it with an ohm meter.

If the fan still does not come on, the fan motor is bad.


My car is an 86 Vert just like yours.

 

Sweet write-up.

thanks.

 

So what did you find? You have not told us anything in a while.

 

oops! :o
I finally got it fixed late at night and went right to bed... forgot to post..

It was the motor itself.

There is a vette-specific salvage yard around me so I went and got a used one for $20.00.

So, other than the time to troubleshoot, it was a cheap fix.