hot at idle

[tnporsche]

Temp runs at first mark or a little above at all speeds with ac off.

With ac on, it runs from 1st mark to half way to 2nd mark.

If stuck in traffic with ac on, it will get to edge of red, in about 5 min.

I think both fans run, but they both come on at the same time with ac sw on.

Water level has been ok and the same for last 5k miles ( fyi Daily driver for last 5k miles after belt change)

Should the fans run separately?

What recommendations to keep its cool, while I stay cool in traffic?

[toolboy62]

I had the same issue although not as severe with my '44 when I first got it; shop recommended simply replacing the radiator. Sure enough, no problems. Apparently at "a certain age" flow just gets restricted enough due to build up of corrosion etc. that it doesnt' transfer heat as effectively anymore.

The temp gauge will still creep up when idling for long periods simply because there's no airflow through the rad, but when the fan kicks on it brings it right back down. For the record I have never had the tray under the engine; I don't know whether that helps or hurts.

nate

[erics944]

I have the same issue, temp is fine while at speed, but stopped in traffic, I can watch it go up. I hope its not the radiator.

[tnporsche]

I guess its rad time. It has 150k or more on it. (unknown because when I got it the odometer was broken. fixed that first)

I have a 2000 jeep cherokee and it did the same thing. I hope the 944 rad is not as much as the jeep. It was 400.00

What about the fans, on same time?

[Techno Duck]

Both fans are supposed to run at the same time. They should kick on at low speed with the a/c button. They will run at low speed at a preset temperature and eventually kick on at high speed at a higher preset number.

Make sure the system is bled correctly.

[tnporsche]

Hmmm I think something might be up with the fans because they only come with ac on, no other time no matter what temp.

I just did some checking and found this on ebay item 260043019657 its 400.00 just like the jeep. LOL I am going to autozone in the morning and see what they have.

[Techno Duck]

Pull the 3 pin connector off the fan switch and jump the pins together, if the fans still dont turn on your relay is bad. Otherwise its likely you have a bad fan switch. I would be willing to bet the later is your problem. The fans will still run when the a/c is on regardless of whether or not the fan switch is working.

http://www.clarks-garage.com/shop-manual/cool-01.htm#laterelaytest

I would not jump the gun and replace the radiator yet.

[tnporsche]

Thanks Jon I'll check that.

If the relay is bad would it still work with ac on?

[Techno Duck]

Thats a good question, i have no idea! I would think if the relay were bad then the fans would not work at all (or they would never turn off).

If neither high or low speed fans do not come on ever, i would be more inclined to think its the fan switch. The relay is one unit, but if you open the unit up its basically a 2 in 1 relay. I would find it hard to believe both sides of the relay failed at the same time.

And i corrected my previous post, the LOW speed fans turn on with the a/c.

Hope it is not the relay, that bugger is expensive.

[todd84944]

Sounds like the temp switch on the rad. is bad as Jon suggested. You don't need to pay 400.00 for a new rad. Find a good used one. that does not leak. I doubt it is the rad anyway. I'm in Nashville. Contact me if you ever need any used parts or help with your car.
toddandcharity@bellsouth.net

[toolboy62]

I agree check the thermoswitch first. I was just ASSuming that you were hearing the fans kick on, I am so used to my old VW's that that's the first thing I check :/

nate

[tnporsche]

Thanks, I am reading the clarks thing and I'll go try those tests.

[tnporsche]

Thanks Todd, You are close. I may take you up on the help some day.

BTY I am breaking ground in few weeks on my dream shop. Its going to be a 18h x 24 x 40 metal building with a full car lift. Open to any Pelican buds.

[erics944]

Every car is different, I changed my thermoswitch and still have the problem. When I do my belts in a couple weeks I plan on jumping the fan connection to test that.

[magilla gorilla]

My t stat has got a mind of its own too.. sometimes it sits just past the first mark..but most times its right at the 3rd mark..and when the air is warm outside, it hovers right below the red at idle..doesen,t look too good, does it??

[Razorback1980]

I would check for air in the system first. That could be one cause as Jon suggested. I don't think it's the thermostat as it wouldn't stay cool at all if it were stuck shut or partially shut. Check out the for sale site here, someone was selling a brand new aluminum one with a larger capacity. If they had been made for an automatic, I would have bought one. I don't agree with buying a used radiator...some things can be used but not all....you may end up with the same problem.

[Eldorado]

i'd suggest air as well..
mine did what you suggest... until i got the air out.

one thing about the thermostat (i think) is that it cant judge the temp of air - only liquid.. I heard that somewhere but forgot where..

[bazar01]

Have you checked the fan rotation?
I've seen 944 with one fan running in opposite direction.
It ran close to red because one fan was pushing air to the front instead of pulling air from front.

[tnporsche]

Ok I did the fan tests using
http://www.clarks-garage.com/shop-m...m#laterelaytest
Low speed comes on with key off (is that normal?)
High speed does come on with jumper (but I dont think I have ever heard them run that fast)
Low speed does come on with ac

THe two resitors at the firewall are for the fans right?
Should I be able to force the high or low speed to come on by jumpering there? (I tried it and it did nothing, key on)

rotation looks good on both, one was hitting the guard. I readjusted it so it does not hit.

I'll check air in the system now