sherminator866

94 22re 135k 4x4. the truck runs great and always runs less than 1/8 temp. if i go up a really steep hill and have to run in first or push second, or if i just let it idle for 15 mins or so, it will get really hot almost to the red. once i start driving again it cools right back down to where it always sits. coolant is fine, i just replaced it when i took the lower hose off for alt replacement. head gasket is newer also. first why is it running so cold while driving (everything ive ever had rode at halfway always), and why does it only get super hot at idle or under a big load? tstat, waterpump?

thanks guys

4x4climber

bad fan clutch... Does the fan ever "catch" and spin faster at higher rpms or when it gets warm?

pruney81

I'm willing to bet it's the fan clutch as well, they seem to often be the most overlooked component of our cooling systems when problems arise.

Hilux808

This does sound like a bad fan clutch. At idle the fan is not spinning fast enough to pull enough air through the radiator for sufficient cooling. If the fan clutch was locked like it should be you wouldn't have this problem at idle. When you drive the incoming air is enough to keep the engine cool. This is also assuming that everything else in your cooling system is working properly, no clogged or plugged radiator, nothing in front of the radiator to prevent air from cooling it, proper coolant/water ratio, all hoses being in good condition and not collapsing, etc.

I just changed my fan clutch yesterday on my 22RE, I would highly recommend that you get a factory OEM Aisin-Sekei Fan Clutch. It will cost more then aftermarket but it's much better quality and it will outlast any aftermarket fan clutch. Look on ebay for cheaper then dealer prices. Got mine for about $90 shipped instead of the $130+ from the dealer. This is the Aisin part #16210-38060.

sherminator866

yea, i never would have guessed that. sounds like it could be the problem. any way to test it to see if it is bad or going bad? also how big of a deal to change one out? i fix everything myself anyways, just seeing what to look forward to.

WHAHAHAJR

Not too bad. A lot easier if you pull the radiator. 4 nuts for fan clutch to water pump and 4 bolts from fan to fan clutch.
Mine seamed to be working correctly but I was having the same symptoms as you so I replaced it anyways. Now when it kicks in you can really tell big difference in air flow.

Hilux808

The hardest part is getting to the 4 nuts that hold the clutch on the belt pulley and trying to work around the belts. You would have more room if you pulled the radiator out but it's not required. I leave the fan on the clutch. Once you have it out just install your fan on the new clutch and bolt it back on the pulley, that's it.

WHAHAHAJR

Pull the radiator. A little more work but saves time in the long run.

snobdds

You don't need to pull the radiator. Just get the shroud out of the way and the fan and your there. 10 minutes - tops...

Buck87

^^^ Concur

1990yota-pickup

its a easy job, no matter how you cut the pie...

WHAHAHAJR

Did not think about just pulling shroud. I only pulled the bottom section of the shroud and after fighting with the lil fan clutch nuts which seemed like forever I pulled the radiator. Oh well when I did it I went ahead and flushed radiator and cleaned fins at the same time.

Bazookaxxx

I just take a piece of rubber hose cut and hose clamp it between the fan and the clutch. Runs full tilt all the time. Or just buy a new clutch. :-p

Buck87

If the rubber hose/hose clamp trick fixes the over heating problem then you definitely need a new fan clutch.

sherminator866

thanks alot guys for the info, im going to flush the system and probably change this out this weekend. even if it doesnt fix it, if its not that hard i might as well.

4x4climber

haha.. if it dont fix it.... it will. your fan clutch is the problem. read up on how a fan clutch works. SUPER easy fix. easier then changing out your 710. u need to take off the shroud and have a box end/open end 10mm wrench. from first bolt to last it should take 30 minutes to switch them... if you are slow. good luck with it. let us know how it goes when you are done.

steps
1. remove top radiator hose from radiator (IF necessary to remove shroud). leave it on the motor.
2.remove the fan shroud.
3. remove 4 10mm bolts. REMEMBER the fan has larger and smaller openings between the blades. they are not the same. work thru the larger seperated areas.
4. put the new one on.. put shroud on. put hose on. yer done.

good luck fixin yer truck man.

Buck87

For out on the trail the rubber hose/hose clamp idea sounds good to get you home. It should be in the using things not as they were intended thread.

sherminator866

So do u guys think my tstat is maybe stuck open? I'm just curious why the truck always runs very cool like 1/8. I'm thinking that's why. What temp do you guys run for tstat?

angrybob

Something you may want to consider (coincidentally from today):

https://www.yotatech.com/forums/f116...h-tech-239448/

This way you know it will be right and there won't be any surprises.

ZUK

iTrader: (1)

Yes shirm--- You have 2 issues....the thermostat is either stuck open ....or simply is not there. Did you recently buy this Toyota? Previous owner probably tried to solve the overheating issue this way. I have experience with removing my thermostat on my 85 model.....took forever to get to 1/8.

issue #2 is your radiator is clogged. I(f this overheating occurs at speeds of about 45 mph or more then there's a 99% chance it's the radiator. A flush will do NOTHING to fix it. A new one is the solution. So many radiators seem to be clogging...and it is almost always the LAST thing that is replaced. I know...it happened to me but not before the headgasket saw too much stress and had to be replaced.