Heated Up

[chockey]

My auxiliary fan is not working, new fuse and connections are tight. What is the best way to trouble shoot this problem? Disconnect the connection and put a volt meter in line, when the temp reaches 215 the heat switch should close and voltage be at the connector. Also where is the heat switch and how would I check that?

Chuck:confused

 

[DDLS3]

Chocky

The aux fan is only energised when the A/C is turned on. If you prefer to have it run at other times you will need to install a bypass switch. The temp sensor in mounted in the passenger side cylinder head betwee the back two cylinders. The aux fan relay is located all the way to the front of the engine compartment also on the passenger side. Turn on the a/c with the engine running and locate the 12 volt source on the relay, then locate the wire from the temp switch and put a jumper across. The relay should pull in and fan should run at this point.

 

[Dave L.]

Without the AC on the original temp switch does not close until 238 degrees...way to hot for my liking...I replaced mine with one that closes at 205.

Dave

 

[chockey]

Thanks for your replies and this brings up more questions. My manual says that the fan will start at 214 deg and shut off at 192 but the temp has been getting really high 240+/- so I put the heater on to drive down the temp. If in fact the fan doesn't turn on til 238 then I have something else to worry about, the water pump in new fall 2002 and the radiator is full, I must have a circulation problem as the temp never started rising til last week.

I will try forcing the fan to run and maybe its bad and look into replacing the temp switch.

With a little work the money pit will drive again.

Thanks Chuck

 

[Dave L.]

Chuck - Also check your lower rad hose and make sure it has one of those springs in it to keep it from collapsing. For sh*ts and giggles I'd put a new thermostat in also. My cooling fan has only ever come on one time without the AC on that I know of. My car on even the hottest days barely reaches 200.

Dave

 

[Nut]

Dave.... how much for the 205 temp switch? Mine runs WAY too hot for my liking too and I have never heard mine come on either. And I was told by a Vette mechanic that you don't want to bypass the circuit with the switch. Your thoughts?

Thanks............ Bob

 

[Dave L.]

Bob - I think I got that replacement sender from Mid-America. I'll check my reciepts tonight and give you the part#.
I can't really see how that would hurt the system. However my thinking is if your running so hot that you need to run the electric fan more than normal conditions dictate,maybe there is another problem?

Dave

 

[DDLS3]

Bob,

I ran a parralell loop so my fan can run when the a/c is on or run continously if I switch it on. I ran my fan steady when I drove from Maine to BG with no problems. Just causes the t-stat to be a little more active. The way I read the wiring diagram the aux fan is only in play when the a/c relay is picked up.

 

[Dave L.]

Bob - Mid-America (1-800-500-8388) has that sender kit. Ask for part# 601-972 $19.95. Activates fan at 205.

Dave

 

[chockey]

Dave
When I put a new water pump on last Sept. I put on all new hoses, upper, lower & heater but I never thought to change the thermostst which is probably OOOOLD.

This is an easy fix.

Thanks
Chuck

 

[DDLS3]

It is very possible that the t-stat is not opening completely. That is a very good place to start and may solve the problem.