22re overheating

yotared

yotared

Member
Joined
Apr 13, 2008
Location
Vale NC (15 miles South of Hickory)
My 93 Toyota with a 22re 5 speed keeps overheating. It has a new water pump and thermostat. The radiator, engine block and heater core were flushed out. It ran good for about 50 miles then the heat went cold and it started to run hot when I slowed to turn or when stopped. I have no idea where the water is going. Its not in the oil and no white smoke out of the tail pipe. Nothing is dripping on the driveway. Someone told me some of the baffles may be stopped up in the radiator. There was a lot of trash and gunk when I flushed the system out. But the radiator is only 5 or so years old. I am at a loss at what to do. Do any of you think I should have the radiator cooked and cleaned out?
 
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Did you purge all of the air out of the coolant system? If not, it may not have been full from the start. Park the truck on an incline nose up. Fill the radiator and let the engine run till it gets to normal operating temp with the heat on. Once the t stat opens and coolant starts flowing, just keep topping it off till it wont take anymore.
 
^^^^^^
Good call, if I remember correctly you need to leave the radiator cap off while doing this. Please correct me if I am wrong or just being dumb.
 
I always left it off while it was running. Keep topping it off as it gets sucked down. When it dosent want anymore, it wont take it.
 
^ Good advice, also check thermostat. I went through two bad vato zone units before I got a good one at the dealership.
 
Well I purged all the air out like was said and it still overheated. A friend of mine that thinks the radiator is stopped up checked the temperature of the radiator and it was 70 degrees difference from the top to the bottom of the radiator. He thinks it stopped up at the bottom, what do you guys think?
 
upper hose should be hot once thermostat opens, if your fan ( and fan clutch ) are working properly, the lower hose will be cool too touch when sitting at idle.

is there any pressure on the system at any time when the cap is on and tight ? freeze plugs are hard to see below intake or exhaust manifold, there is a plate on the rear of the head that the gasket fails,there is also a freeze plug on rear of block.

under intake is a tube that is sealed by an O ring, that fails as well.

fill then pressurize the cooling system, and watch the pressure gauge, does it drop ? it should hold and maintain minimum 13psi, if it doesn't hold pressure, it's not going to hold coolant either, so it should show you where you're leaking as well. this will also pressurize all the hoses ( turn heater on hot ) and heater core as well. don't exceed 20 psi or you could create problems you didn't have
 
Blkvoodoo said:
upper hose should be hot once thermostat opens, if your fan ( and fan clutch ) are working properly, the lower hose will be cool too touch when sitting at idle.

is there any pressure on the system at any time when the cap is on and tight ? freeze plugs are hard to see below intake or exhaust manifold, there is a plate on the rear of the head that the gasket fails,there is also a freeze plug on rear of block.

under intake is a tube that is sealed by an O ring, that fails as well.

fill then pressurize the cooling system, and watch the pressure gauge, does it drop ? it should hold and maintain minimum 13psi, if it doesn't hold pressure, it's not going to hold coolant either, so it should show you where you're leaking as well. this will also pressurize all the hoses ( turn heater on hot ) and heater core as well. don't exceed 20 psi or you could create problems you didn't have
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If it is one of these thing would it drip or leak while parked in the driveway. Or would it only leak while the engine was running?
 
yotared said:
If it is one of these thing would it drip or leak while parked in the driveway. Or would it only leak while the engine was running?
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Maybe not, it may not leak until things are under pressure, a that point it may evaporate before it gets to drip. but you would probably smell it leaking ( sweet smell of coolant )

I see it a lot on equipment, never a puddle, but it's always loosing coolant, ( of course the operators never smell a thing until the engine cooks )

that you oil isn't chocolate milk looking is good, even a little water/coolant would make it milky after repeated events.

if the radiator is original, it very well could have a restriction, is this a brass rad or aluminum/plastic radiator?

Has the coolant ever been mixed ( green>Red DEXCool ) this could cause a sludge in the system that can cause problems.

TOYOTA RED coolant is NOT DEXcool, while it will mix with green with little issue ( unlike mixing with DEXcool ), it shouldn't be.

TOYOTA RED has electrolysis/corrosion inhibitors that a lot of green coolant does not have.

Where were the water pump and the T-stat sourced ? I have as well run into bum t-stats and a few water pumps where the impeller would spin on shaft and not push as it should.
 
The parts came from AutoZone. The radiator has plastic top and is aluminum the previous owner had it installed after he bought it had set for 3 years when he got it. He only drove it on the weekends he had it 2 or 3 years then I bought it have had it almost 2 years never drove it far till the last few months I moved and now drive it 60 miles a day 5or 6 days a week. I can smell coolant some times and have had to add a little coolant every now and then in the pass. I have only put green in it can't say what they did. When we flushed every thing alot of gunk and sludge came out.

I have never done a pressure test how do I go about doing this?
 
cooling system pressure tester is something you may have to rent if you don't have a buddy that has one,

looks similar to this (you will need the appropriate adapter for your radiator)

http://www.thetoolwarehouse.net/p-42522-cooling-system-pressure-tester.aspx

link is to one of the cheaper models, but it works fine ( and has multiple adapters )

I don't know if 'Zone or AA have one for rent.

before you get crazy with that, you say the truck has been sitting. Look between the radiator and the AC condenser for leaves, nests, pine needle build up, all that kinda crap. no air flow means no cooling. Also, pull the grill and shine a BRIGHT flashlight thru rad/condenser cores, you should see light on the other side, mud and other crap in the core fins will also cause no air flow.

also, there is an issue with SOME thermostats called " Temperature overshoot" where it appears the engine is over heating on the dash gauge ( and technically it is ) but the thermostat has not opened "yet". It will and does open, but not until the front part of the head is hot enough to allow the T-stat to do it's thing. Toyota has a specific thermostat for this, don't know if aftermarket has addressed the issue or not.

The temp sensor is in the middle of the head/intake, the t-stat is toward the front and doesn't get the same coolant flow until it starts working.

none of this addresses the loosing of coolant though unless it is actually getting pushed into the over flow bottle ( it does have one right ? ) which it will do when over heating.

Is the radiator cap good ? does it have a good seal ? no cracks ? no seal means no pressure, which also allows it to dump coolant when at operating temp, which could also give the impression of over heating. dumping into recovery/overflow tank or on the ground if it doesn't have one.

if there is no over flow/recovery tank, you're dumping coolant when the engine gets to operating temp, but it's sucking air and will not refill the system when it cools down, giving the impression there is a coolant loss ( and there is ) ALL newer ( since the early '80's) vehicles have a CLOSED cooling system they don't loose coolant to set the level, it is captured in the recovery tank.
 
The new radiator was put in after it was sitting for a few years. The cap still looks to be in really good shape. And it still has the overflow tank. It always has some coolant in the overflow even when the radiator is low. Seems to loose a gallon after fifty miles or so.
 
yotared said:
The parts came from AutoZone. The radiator has plastic top and is aluminum the previous owner had it installed after he bought it had set for 3 years when he got it. He only drove it on the weekends he had it 2 or 3 years then I bought it have had it almost 2 years never drove it far till the last few months I moved and now drive it 60 miles a day 5or 6 days a week. I can smell coolant some times and have had to add a little coolant every now and then in the pass. I have only put green in it can't say what they did. When we flushed every thing alot of gunk and sludge came out.

I have never done a pressure test how do I go about doing this?
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Another leak source thats overlooked is the allen plug located directly under the center of the cam. Under the flange on that plug is a flat aluminum gasket/washer. My local Toyota garage diagnosed a cracked head (pressure tested) because that allen plug was loose. They installed a new head. I kept the old head, took it home and was checking for a crack when I found that plug loose and signs of a coolant leak on the aluminum gasket. Took head and my findings BACK to the shop. End result was...kept the new head plus got my money back. Symptoms initially was a VERY slow coolant loss. No milky oil, no snot under the oil fill cap, no external leaks, no smell. Maybe 1 or 1 1/2 pints consumed every thousand miles. Engine ran fine, plugs looked good.
 
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