Defective fan clutch?

[MisterTurbineTwister]

Weather or not you need a fan clutch at high speeds, your fan clutch is designed to lock up at higher temperatures to cool the engine at full capacity. I would quit solving around the problem and replace it. I had a bad clutch on my car, only it went out the other way. The rear bearing seal went out and it was always locked up. Talk about a noisy ride! I thought I was going to explode something at 3000RPM!

You could be experiencing a multitude of problems. Think about what a blown head gasket does to an engine. I replaced my HG about 8 months ago and I ended up replacing the fan clutch shortly after.

The oil and antifreze in a BHG situation are unified into a wonderful mixture of rust colored paste. Besides having the two fluids mix inside your oil pan, turbo and radiator, most engines overheat when a BHG takes place. This does all kinds of unseen damage to anything heat sensitive (including the lockup in the fan clutch and the radiator core).

I was fortunate enough to have the head gasket blown in my neighbors driveway before I bought it from him right after it did, so my car was never driven or even run enough to overheat with the BHG, so I didn't have to replace my radiator.

I did have to replace the radiator in my '89 Cressida (7M-GE), though which was driven on the BHG before I bought it and replaced it about a year ago, along with the fan clutch. I bought a good tight used clutch for the cressida and I have had no problems with the $15 spent on it.

Don't underestimate the cause of the problem. A cooling system is the simplest and usually the least expensive system to work on in a car. You should eliminate the problem with a new clutch and your new radiator.

 

[CSquared]

Just to update... i switched radiators and it made no difference. Mine was surpisingly clean... The previous owner supposidley replaced it within the last 2 years anyway.

I am now officially lost...

Just to add in some additional info... It seems like it's been happening ever since i replaced my heater control valve...

 

[MisterTurbineTwister]

Your heater valve should have nothing to do with the overheating problem with one exception. If your heater core leaks, you lose antifreeze. If your exchange valve was always closed on a car that has a bad heater core, the new replacement opens a door to lose fluid.

If your car does not lose fluid, this is not the problem. It sounds like you need a fan clutch or possibly a new shroud (if yours is broken or missing partially.) The only other thing that could be causing an overheating problem is having a crud filled block or head.

I'm not too familiar with the cooling passages in these engines, but I know that some engines have smaller passages in the head or heads (where most of the heat is created) and it doesn't take much to block passages. Aluminum heads can see some corrosion, but usually you don't see much blockage in aluminum parts because build up is usually rust related.

You can call some local oil change shops to have it cleaned for about $35, but start with the fan clutch. If that fails, have the system cleaned (not with a garden hose, have a shop run the 250 degree acid and detergent through it.)

 

[CSquared]

Actually when we did the headgasket in january i pretty much rebuilt the top half of the engine. Head was removed... cleaned... resurfaced. So that doesnt seem likely.

The fucking fan clutch by the way is about 250 bucks from toyota :icon_frow

The guy told me that when i called... I seriously wanted to reach through the phone line and strangle him.

Crooks.

oh... also no i am not losing any fluid...

Thanks for your help throughout my trials and tribulations

 

[IJ.]

Delco make one that's heaps cheaper than Toyota!

 

[CSquared]

yeah there are knockoff ones for like 60 bucks... a friend of mine was ranting and raving to me though about how toyota parts are awesome and he knew a guy who used a knockoff part that snapped and tore ass into his radiator and upper hose.(he works for toyota)

I mean generally i dont fall for stuff like that... but he suceeded in turning me off on knockoff brands.

Actually though i have a set of DSM fans on the way. Not sure whether or not im going to use them yet.

 

[IJ.]

If it was some cheap nonamemadeinTaiwanwhitecardboardboxPoS I might agree, I'm running one on my Supra and it's fine!

Everything I've read about the Electrics indicates they don't cope at low speed stop start driving in traffic so I'll stick with the engine fan.

 

[GrimJack]

Find out what the price is on the Tundra clutch for the fan - it activates at a lower temp and might be a bit cheaper.

Also, try calling Jay Marks and see what price they give you on it. It's cheaper for me to order from there and pay the shipping than it is to get gouged by my local Toyota dealer.

 

[MKIIINA]

haha actually he is a certified toyota mechanic and it was his head mechanic guy that suggested that method of testing.....

we had a local guy who was a certified toyota tech do his own rebuild. he also was able to snap an arp and a few tranny bolts and the new rebuild started knocking after 1500 miles.... reason? improper bearing specs


so far my faith in toyota trained techs is just above buying hair care products from sher..... this just helped....imagine if that fan had been weakened before and with the added stress of the hose decided to shatter...... i have seen a clutch fan grab a screwdriver and throw it with enough force to leave a nice dent in the underside of an opened hood..... lets have him put down his tools...step away from the car and sit on his hands :thumbsdow

 

[CSquared]

haha actually i've had the fan shoot a 12mm socket at my head. A friend of mine accidently dropped it while we were standing over the engine bay. I got out of the way in time though.

 

[Ckanderson]

lol i tried to talk to him and get a discount... I started explaining "problems i am having with my wife"... and he left the room.

So maybe i wasnt talking to a computer? :icon_conf

I feel like an ass now... thanks.

:lol: :momaru:

 

[bluemax]

Try your water pump. I read an engineering article on faulty water pumps.
A water pump can cause cavitation in the water and generate heat. The faster the pump turns the more cavitation there is. Cavitation is caused by faulty impeller fins. I don't think you can really tell if the pump impellers are faulty or not. But it was recommended that you get only original new manufacturer replacement pumps. Remanufactured pumps can also cause problems.
Just a thought.

 

[MisterTurbineTwister]

Checking the water pump is a good suggestion. Most of the time where you see water pumps fail is if the cooling system has been neglected and run with too much water. Usually in older cars or in vehicles that have sat untouched with fluid in them for 8 or more years.

If the antifreeze was disgusting when you changed it the first time or if the car was sitting for a long time (years) before you changed it, the bearing could have lost it's seal (usually the case) and it locks up or has a lot of play from the bearings coming unseated.

Usually when a water pump fails, it will let you know by moving the pulley and usually make horrible noises or feel loose.

If your head was tanked when you rebuilt it, the block still could have quite a bit of rust build up in it. This tends to be a bigger problem towards the back of the engine, especially on an inline six engine compared to a V configuration engine or horizontally opposed inline 4 cyl. You would be amazed at how much mud you can pull out of the back of a 15+ year old engine if you take the freeze plugs out.

A realy nice way to check your engines cooling efficiency is to use one of those infa-red read out thermometer lazers. You just point the red dot at whatever you want to check and it will tell you a dead accurate readout down to the 10th of a degree in that exact pinpoint area.

They cost about $100 (on sale at Harbor Freight for $69 http://www.harborfreight.com ) and are awesome to have for a turbo car! You'll get lots of information from the areas of your engine bay and it realy helps keep things cool. We found a 470 degree difference in the exhaust housing of the turbo and the heat shield on my '88 7MGTE!

They realy help to find dead spots in your cooling system and detect rust buildup in your engine block. You can also use them for making a more efficient IC system and tell you where to and where not to run your IC pipes and what to make them out of.

Just on a side note, but interesting enough, we found a 1.5 degree difference between the black and white 2 tone paint on the same door panel, inside a garage when it was 72.2 degrees ambient air temperature. This was out of sunlight, in a garage with the doors and windows shut with the colors right next to eachother down to a color against color breaking line.

 

[CSquared]

Well i put the fan clutch on order so i am picking that up tomorrow. Also while under the hood i am going to kill some coolant and add more water as per suggestions from a few guys on supraforums.(right now im running about a 85% coolant 15% water mix and they said that was too much coolant)

Does it make any difference that the car wont do it on cold nights? Like on the way to school during the day if it is warm my car will start to pull that crap but then on the way back when the sun is set i can beat on it all i want without the temp gauge reacting.

Honeslty im not sure how long the waterpump was dormant but most of the components in the engine are from one of those "30,000 mile JDM" engines. The coolant was pretty clean when we did the HG. No oil got into my coolant lines it was only the other way around.

 

[GrimJack]

85:15 is way too heavy on the antifreeze end of things. That might fix you up right there.

 

[CSquared]

85:15 is way too heavy on the antifreeze end of things. That might fix you up right there.

man i hope it's something as stupid as that... That'll be the first thing i do tomorrow then.

 

[IJ.]

Is that 85/15 Coolant concentrate/water or premixed coolant/water?

 

[CSquared]

No it's not the premixed stuff... it's concentrate with water.

 

[IJ.]

Cool no wonder you're having problems !!
50/50 is about as rich as you want to go!

 

[CSquared]

Cool no wonder you're having problems !!
50/50 is about as rich as you want to go!

meaning i want the coolant to be the lower %?

Honestly i had the same conversation on sf... Usually i do buy the premixed stuff so i guess that's why i never had any problems before.

If this does work... i am officially an f'n idiot.