I have an annoying problem. I recently replaced my old head with brand new one, new head bolts, new toyota factory head gasket and the Crawler cam from EB. Now it seems to get hot then cool down and them get hot ect ect. every time I drive it. I checked and re re re checked the timing and the timing gear marks and every thing checks out. It runs fine, just wants to heat up. Also I've noticed no noticeable increase in low end torque with that cam shaft either, which is depressing. I had it into the Toyota dealer here in town assuming they could figure it out, and its already back there, cause they didn't fix it the first time.

I'm at my wits end after putting over a grand into it and it not running right. Please help so I don't have to sell and part out a totally decent solid axle '85 SR5 Runner. I love the truck but I've had it!

Probably don't have all the air out of the cooling system.

Jack/block truck or park on an incline. Turn heater ON (not fan, but the valve).

Remove radiator cap; run truck for about 20 minutes. Once the t'stat opens, you should see coolant circulating, and the air burping out of it. Check the coolant level when finished to make sure it's topped off.

Also, if it overheated before this work, and you didn't replace the t'stat, you might've whacked it.

I did that already, but I didn't have the front end inclined, and I may not have ran it long enough, but I didn't see any more bubbles and I could see the water flowing with the cap off.

Another question though, How come I don't notice any more torque with the EB crawler cam? EB said I would def notice a difference and I did it so I could more easily pull a trailer out west.

What kind of thermostat does it have in it?
- http://www.4crawler.com/4x4/CheapTricks/index.shtml#Thermostat

I just have a O'Reily parts store special? How much does that thermostat cost from the dealer?

I appreciate the responses. I will look into the bleeding of the system again, and the new T-stat.

But is there anything you can advise on the issuse with my Crawler camshaft?

With the radiator cap off, do the bubbles ever quit?

My engnblder.com RV cam is the bomb.

Lots of low end and 105mph top end.

Could you catalytic converter be plugged? Just a thought.

Is it actually over heating or could the gauge be bad?

Does it heat up in the highway, or just in traffic?

Was the HG replaced because of failure, did the over heating cause it to fail?

Definitely replace the t-stat w/an oem stock one, should cost under $15. Check the hoses(for squishiness), the water pump(for seepage) or replace if you don't know the age, check/replace the rad cap, it could be starting to fail. What is the age of the radiator?, it may need replacing or rebuilt.

What other mods do you have to your truck, i.e., exgaust tires, gears, etc.,? if you are running larger tires on stock gears, or have an open/too large exhaust, a cam wont make all that much of a difference.

The overheating issue shouldn't be too difficult to sort out. What dod the dealership do the first time you had it in?

X2
pull that cheap one out of there before you toast your new motor.
funny how people spend so much on the motor then put in a cheap thermostat.
I did the same thing <img src="/forums/images/graemlins/zombie.gif" alt="" /> Toyota thermostat made the really bad temp over shoot go away.

The fact that you had to replace your head brings up the question as to whether or not you had a over heating problem before that caused you to have to redo the top end.

Things that can comonly cause overheating

Slow/ old thermostat- get one from Toyota and check it in a pan of hot water before installing and compare it to your old one. Watch how it opens and closes. A slow thermo stat can cause a motor to overheat especially on a cold morning - the little engine heats up before the thermostat can react , building up excess pressure and often blowing a head gasket.

Also , an inherent glitch in these motors is that when the heater valve is open it seems to cause a regular spike in the temp the engine runs at. When ever I see my temp gauge spike the first thing I do is shut off the heater valve un till the engine levels off at a normal operating temp.

Fan clutch , is yours good? Even a cool running 22r will cycle the fan clutch every so often. If it isn't working it will run hot / overheat.

Radiator in good condition? Water flows thru it top to bottom easily?

Coolant recovery in good condition? If it works correctly, it will purge any air that is trapped in your engine and purge it. Engine heats up , pushes air out , purges thru and out of the recovery tank , and then sucks liquid back in to replace it when it cools. Check the level every morning when the engine is cold. When you first refill your cooling system you'll re-add liquid a couple of times if there was any air left in there. If it continually requires more coolant you have a leak or bad head gasket.

Carbed or F.I. ?

If carbed , make sure your vacuum advance is working properly.

Ok here goes:

Ralph: Yeah the bubbles did quit after a bit and I can see the water flowing by. The exaust is pretty rag tag, If I remember right the catalytic converter is gone. I installed the RV cam exactly like the stock one was in, and I really can't notice much difference and that bums me out.

Snowtoy: I thought the gauge was bad, but It started heating up the other night, and I pulled over quick and killed the motor, and in the dark the exaust manifold was glowing, so I don't think its the gauge or sending unit.

The old head gasket failed yes and my old head was too shaven to be planed again so I bought a new one. It was overheating because the number 2 cylinder was pumping exaust gases into the cooling system.

The following only have approximately 80 miles on them: new oil pump, water pump, radiator, head, head gasket, cam.

I have 33's on the truck and just a muffler barely hanging there. The head replacement was the beginning of the fixing up of the truck so exaust was coming soon. But other than that its bone stock.

The first time into the dealership they replaced the temperature control sensor on the front to the left of the head. That did not rememdy the problem, so I took it back, and after a week THEY don't know exactly whats wrong. They're still trying to diagnose it.

I will get the stock toyota thermostat, but I can't believe that that dealership didn't suggest that already <img src="/forums/images/graemlins/zombie.gif" alt="" />

Cholltero: The fan seems good I checked it while the truck was running. Radiator is new as well as water pump and I flushed it beforehand. The truck is fuel injected.

I was frustrated to find out that toyota couldn't figure out the problem. Now I want to go get my truck back and get the thermostat for it. But the cam thing still has me bugged. I've been told that that cam may have it running hot, but I don't buy it.

I really appreciate the responses, I'm just frustrated.