Overheat (?) problem. How to tell if fan clutch is bad?

I have an '89 Toyota Cressida and the temp guage has started indicating a hot condition. It'll run way up to hot and then dip. Sometimes does it at speed but usually more at low speed/idle. In that respect it acts like you'd normally expect in an overheat situation, however I put in a brand new radiator less than a month ago. When it started doing this I replaced the thermostat, still does it. The engine has about 30k miles on a complete rebuild. Water pump seems tight, belts are snug. If I keep the engine RPMs at around 2500 when standing still, it's usually okay.

The belts are snug, but would a fan clutch cause this kind of condition? How can you tell if the fan clutch is bad? There seems to be a fair amount of air moved at a low speed, but I notice I don't feel particularly more blow back from the fan when I rev the engine.

Other than a bad temp sensor or the guage itself, if the car is actually overheating, what else could cause it?

Thanks for all input

Reply to
Doc
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Hi, My '89 Corolla behaved like this for a while-- when I was in low-speed traffic and/or idling, the temp gauge would nearly max out before the fan would kick in and lower the temp. My mechanic changed the "fan switch" and it solved the problem. Is your car's fan kicking in at the temperature it's supposed to?

Doc wrote:

Reply to
johnyang97

Reply to
dahpater

7M-GE Engine...NOTORIOUS for blowing through Fan Clutches.

You can buy one on E-Bay for $20-25 Buy It Now...the SAME fan clutch I paid $80 for at AutoZone.

And believe me, when you replace it, you'll KNOW it's working! Sounds like a B-17 taking off!

If you can spin the fan with the clutch COLD then it is probably bad. There should be some resistance cold, little resistance when somewhat warm, and more resistance again when hot. What I did was I drove my Supra until it started overheating, stopped the car and shut the engine off. (Since this is not an electric fan there's not much danger of losing a finger...). I spun the fan and it spun freely. I was well over what was normal for the engine, so there should have been some resistance.

When I explained my overheating problem in a Supra forum, they all said to check the fan clutch.

Good Luck.

Reply to
Hachiroku $B%O%A%m%/(B

Got one at Autozone for $39, lifetime warranty. Advance wanted

90-something and they had to order it.

Definitely seems to be moving more air. Remains to be seen if it cures the problem.

When I gave it a quick snap, it went maybe 1/2 - 3/4 turn. The new one is clearly much stiffer.

The car seems to be running okay, hopefully no damage was done running hot.

Reply to
Doc

WHAT?!?!?!?! $39!!!!! Man, my poop-chute hurts!

DURALAST_NEW BWP-690 LLT $74.99

For the Cressida: TORQFLO Thermal 922653 LLT $39.99

Now I know not to mention the word "Supra" when ordering parts!!

But, it may have something to do with the Cressida having a real grille openeing, while the Supra has a little slit and the opening at the bottom of the air dam. The fan must need to suck more air and probably has a stiffer clutch.

Damn! You move fast! When the heck did you do this?

Well, that's not too bad. Mine just kept spinning. Let us know what happens...

Reply to
Hachiroku $B%O%A%m%/(B

Got one at Autozone for $39, lifetime warranty. Advance wanted

90-something and they had to order it.

It concerned me a little that he said it may happen at highway speed but more often at idle.

For many engines, you need little or no fan at highway speeds. At idle, the fan clutch, or electrical fan control system, needs to be working because there wont be any significant airflow past the radiator to do the cooling otherwise.

So I suggest that the OP test the clutch,or fans, before he starts throwing more parts at the car. We would assume he doesnt have an air dome in the engine, or a gasket or crack in the block or head that is sometimes opening....but a little diagnosis might save time and money down the road.

Reply to
hls

Man, after I replaced the clutch, the first time it came on at highway speeds it freaked me out! Like I said, it sounded like a B-17 taking off!

Yes, on the Supra it often kicks in at highway speeds, esp in warmer weather. The car was overheating more at highway speeds than at other times. I could drive for about 2 hours at lower speeds before it started getting hot, but only 45 minutes or so at 65-70 before the needle started reaching for the red.

Reply to
Hachiroku $B%O%A%m%/(B

As a folllow-up, the new fan clutch seems to have cured the problem.

Reply to
Doc

That is good news.

But, I have one question...how the HELL did you wind up paying $39?!?!?!

I went to AZ (Shoot...I went to AZ EVERY DAY for about TEN DAYS!!!) and asked them for a price on a fan clutch for a Cressida...$86, same as for the Supra.

The only thing I can figure is that they had a DuraLast (their brand), a Beck-Arnley (even MORE) and on that was shown as N/A. You must have gotten that, and probably the last one at that!

Reply to
Hachiroku $B%O%A%m%/(B

AMC...catch "12 o'clock High" some time.

GREAT war movie (if you like War movies...I happen to be a WWII Buff, esp Pearl Harbor and the Air War over Europe). If you can get through it without falling asleep...it's 2:15 long!

One thing you have to remember...none of the war scenes were staged. They were filmed by the Air Force and the Luftwaffe during actual combat. There's one scene where the photographer has JUST focused in on a '17, and it's gone. And it was REALLY gone.

Quite a sobering thought while you're watching the movie...

That, and the airport 2 miles from my house had a B-17 there for years...

Reply to
Hachiroku $B%O%A%m%/(B

Perhaps the pricing structure varies depending on where you are? I'm in Florida.

Reply to
Doc

Mass...which is almost as warm as Fla this year!

Reply to
Hachiroku $B%O%A%m%/(B

And if that's the case, I'm sending YOU requests for parts, cause if it is, paying the shipping is STILL cheaper!

Reply to
Hachiroku $B%O%A%m%/(B

My 89 is doing the same thing. The fan hardly spins when cold. There are also two small electric fans. Should they kick on? Where is the temp switch?

Reply to
GreenishGray

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