Jef Free

87 22re itasca motor home that at low speeds, traffic jams, standstill etc temp starts to climb. I thought I finally figured it out today and removed the auxiliary fan thinking that it was a detriment rather than an asset by blocking Sue flow. No go tonighta relatively cool night with light rain and after sitting idling for just minutes temp wants to climb. System has been flushed, new radiator and thermostat no kinked or leaking hoses and compression and radiator test so no blown head gasket. I cannot figure this out. He’l help
thanks

az4x4runner

If it's only getting hot when you are parked it sounds like the fan clutch is going out. Enough air passes through the radiator when you are driving to keep it cool, but at idle the clutch should stiffen up (slip less) causing the fan to spin faster and draw more air in through the grill.

Jimkola

Agree with suspect fan clutch.
You can recharge the clutch with silicone, but a new Aisin clutch is pretty cheap, easier to just replace.

Robert m

iTrader: (2)

What thermostat did you use? Is it a single or dual stage? If only a single, try a dual stage. 22re engines can have issues that cause overheating at idle caused by the thermostat. Search for "temperature overshoot" on here or Google and you will find info about it

87-4runner

Few people clean their radiator... I'd give it a good cleaning at the car wash also.
radiator cap should be in good shape as well for the cooling system to work properly.

millball

Lay hands on a decent IR temperature gun, and determine what 'hot' actually is.

You don't mention any boil-over coolant loss.

highonpottery

iTrader: (1)

When you replaced the thermostat and radiator, did you make sure the jiggler valve thingy on the thermostat was in the correct position? (I believe within 30 degrees of vertical)
I'd also look into the fan clutch, they're only like $50

rattlecanpaint

I had to cut the jiggler thingy out of my son's truck to get the damn thing to bleed all the air out of it. Also 30 degrees of vertical? Tstat is in there horizontal. (Which is part of the reason they are hard to bleed)

Also, you from Newcastle Colorado?

2ToyGuy

I've never had a bit of trouble bleeding the air out of my 87's. I put the jiggler pointing directly to the firewall.
I park the truck on a incline, or hill, whatever, make sure the radiator is dead full, and the recovery tank is up to the line. I put the radiator cap on, but only to the first tension, turn, twist, however you say it. There are two twists to tighten the cap completely. If it's only to the first twist, it allows the coolant to flow out, and get sucked back in with equal ease, but it doesn't allow the coolant to overflow as the truck heats up. It directs that overflow into the recovery tank.
Start it up, and let it run for 20-30 minutes. MORE than enough to allow the thermostat to open completely, with the heater set to full hot. Once it's hotted up, I shut it off, and fully tighten down the radiator cap. USE GLOVES, it hot!! I let it cool off for a couple hours, make sure the radiator and recovery tank are both properly filled, and away it goes. If there's a LOT of trapped air, repeat the procedure.

That's all I've ever needed to do. There IS a substance called Water Wetter, that really reduces the surface tension of the water in the cooling system, and can really help bleed off any air, but I've ever needed it.

Anyway, I wish you all the best...
Pat☺

Jef Free

Thank you all.
i only have the single stage thermostats and I have never been informed about the little juggler thing but it sounds easy enough to jiggle.
the fan clutch I am not sure how to test and when you say the temporary fix is dilution do you n mean to spray it with silicon.
The radiator is brand new so no cleaning nessacary.
I do not know what a IR gun is but all ears. Does that determine exactly where it’s hottest. No I am not from new castle Colorado I am from Nubiro.
On a hunch I removed the auxiliary fan thinking it was a detriment rafter than an asset to the engine and have not given an adaquate test to have any scientific results but we will see. I also had to remove the bottom plastic skid plate to easier access my crank bolt for valve adjustment and decided to leave that off for a day or two to see if that would increase airflow.
Thanks again all of you

az4x4runner

Checking the fan clutch is pretty easy but there isn't really a spec to go by, just feel and an understanding of what it is expected to do in different conditions. It should have some resistance if spun by hand when cold/engine off (maybe ~1/4 turn), otherwise it is allowing too much slippage. It should run at high speed when you cold start the truck (it'll be much louder and blow a lot of air at you if you have the hood open), then slow down in 30-60 seconds I would guess. When you are idling at a stop light the air around the clutch will heat up from lack of air flow and the clutch will slip less, this results in more air noise from the fan when accelerating away from the stop. Check out this thread: https://www.yotatech.com/forums/f116...clutch-283631/

IR thermometer example: https://www.harborfreight.com/121-in...ter-63985.html

Jimkola

Some(not all) 22RE's had an annoying habit of getting too high on the temp gauge before the thermostat opened and the temp dropped down to what would be considered normal(half, or a tad under). Toyota called this temperature overshoot and designed a modified dual stage thermostat for these vehicles with the concern. This affected Celicas, Trucks, and 4Runners. I'm talking about vehicles virtually new at the time, maybe a year old. Toyota never told us what caused the issue. It was pretty much limited to 83-early 1985 vehicles. Those manufactured after that were fine.
So, if you start your vehicle cold and the temp climbs to 3/4 before the thermostat opens and drops it back down to roughly half way than a dual stage could be in order. Regardless, If you have a non factory thermostat I'd recommend a Toyota brand.

The fan clutch typically engages at idle or low speeds when airflow is poor. If your vehicle is idling and the temp is climbing up that's when it should engage. When the engine's coolant is under a certain temp the fan clutch sorta free wheels. It's spinning, but you can actually stop it with your hand.

A infra-red Temp gun are pretty cheap and gives you confirmation that your dash gauge info is accurate. or not.

Our approach bitd after verifying gauge reading was:
1) block test
2) Pressure test and check for external leaks
3)pull thermostat and test. Put a new Toyota brand thermostat in regardless. We often saw thermostats go wonky once removed from system for any reason.
4)pull radiator and send to radiator shop for flow test. A radiator in good external condition could often by rodded out. Dying art these days, I'm sure.
99% of the time it was fixed by step 4. A few times a new waterpump was needed, but those were isolated cases with extenuating circumstances.
Was the radiator replaced trying to fix this issue, or was the radiator replaced for another reason, and then started running hot?

Jef Free

thanks all
can anyone tell me what kind of silicon grease and where to get and it is that a pretty self explanatory process to repack the fan clutch

Jef Free

also some resistance when cold and it spins for 5 seconds or so when turned off. I can get my hand in front of it by ac and I cannot feel any air being moved??

Jef Free

there is air being moved when cold I just noticed

2ToyGuy

It's not a grease, and you don't "repack" the fan clutch. You need a liquid silicon. I'm pretty sure you need less than 1/2 pint, total. It's about as thick as Karo Corn syrup, when the syrup is cold. Looks a lot like it too.
I'm not good enough to tell you a step-by-step. I've seen a thread someplace, and I can't find the bloody thing now, but from what I saw, you split the clutch in half, on a level surface. I believe both halves are identical, so it doesn't matter which side is down. Having said that, I seem to recall the side that was down was the fan side. There are small, circular, reservoirs around the outside of the clutch. I'm not sure how many. Maybe 4, maybe 6, I'm just not sure. You need to put the silicon in a small plastic bottle with a top like is on a tube of RTV caulking. Those kinds of bottles can be had at McMaster-Carr, or Grainger. Squirt silicon into each reservoir until it's at the top of the half. It's awfully thick, and doesn't flow very quickly, so be ready to sqeeeeeeeze your bottle. Put the other half back on, tighten it down a reasonable amount, to prevent leakage, and away you go. A bead of RTV around the rim of the clutch before it's re-attached can help seal it up.

That spins for 5 seconds, is that cold, or with the engine warmed up completely? Either way, I believe 5 seconds is too long. No way should the fan spin that long after it's warmed up, either.
You should be able to hold your hand behind the fan and feel it moving air, cold or hot. Hotter it gets, the more air it moves. You can also hear a "whooooosh"ing sound when it's good n warm. Kind of a deep roaring sound. It should make the sound on a cold start, for a few seconds, too, maybe 30-40 or so, then it will quiet down, until it warms up.
A test I saw on a Timmy the Tool Man video for if it's good is to fold up some newspaper into a relatively thick strip, and hold it against the side going downward, the driver's side. When it's cold, you should be able to slow down the fan a good deal, when it's warm, not at all.

Really, for the price, getting a new fan clutch is the way to go, IMHO, for what it's worth. Just my opinion, though. They're not that expensive, and they're easy to R&R.
Have fun!
Pat☺

Jimkola

The Toyota silicone is 08816-10001. Iirc one tube typically was enough to rejuvenate a weak fan clutch. Just don’t overfill. But it’s 30-40% the cost of a whole new Aisin clutch. So a new clutch may be the easiest way to go.

2ToyGuy

I found the instructions I mentioned! Great site, it really is. Lots of great information. You might want to check it out. https://www.4crawler.com/4x4/Docs/FanClutch.pdf

Hope that's some help.
I would just replace it with a new one, myself, and have a few times, but heck, your truck, your decision.

Have fun!
Pat☺

Jef Free

thanks
replaced fan clutch and all is well. Should have asked for help months ago and saved a lot of grief.
Is it a worthwhile investment to replace exhaust manifold with a header .
would it give me additional hp and perhaps better gas mileage.
If so where and what kind should I purchase
thanks

87-4runner

Header is a nice upgrade... to get the most though you'll need to get a full flow cat or no cat if you can and larger exhaust pipe... it's all about moving the exhaust out without restriction.
maybe a slight increase in mpg if you can keep your foot out of it.