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Discussion Starter #1 (Edited)
my two and i were making a trip about 40 miles to my new home i am currently moving into, about 39 miles into the 40 mile trip i looked down and saw my temp Gage at H. i quickly pulled over and shut down. i could hear the coolant boiling. my heart sank, i waited a while and tried it and the car started fine but i shut it off and pushed it home anyway.

i have used the search and read other peoples stories and the help offered them.. What should i do first.??

i bled the coolant about a month ago when i was having high rpm troubles.


Where should i start? t-stat?replace coolant?i guess tomorrow morning ill check the oil to see if there is any coolant present and pray my HG is intact.
and help would be very greatly appreciated... :notworthy
 

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I'd remove the coolant and check the thermostat. That's probably the most likely culprit.

You'd have to have a really big HG problem to overheat because of it I'd think...
 

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Discussion Starter #3
thats what i was hoping to hear. also the person that owned the car before me overheated the original motor till it gave up, he replaced the motor and the coolant lines from the radiator to the engine, is it possible the radiator is causing the problem, the prior owner also wired the fans to be constantly on, but they feel like the are pushing air from the back of the car to the front, should i re wire them to pull, or just re wire them to come on at a temp like factory??
 

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Check to see if there was any coolant loss/consumption. Check for oil in the coolant and coolant in the oil. Coolant in the oil looks like a milky white slime and oil in the coolant is a murky brown slime. Smell the exhaust and see if it's sweet smelling like coolant. See if there is white smoke coming from the exhaust. Then test the t-stat to see if it is not stuck closed and you do that by apply heat to it and you will see it open and close.

After you do alll of that post your results and then we'll go from there.
 

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sg1mr2 said:
thats what i was hoping to hear. also the person that owned the car before me overheated the original motor till it gave up, he replaced the motor and the coolant lines from the radiator to the engine, is it possible the radiator is causing the problem, the prior owner also wired the fans to be constantly on, but they feel like the are pushing air from the back of the car to the front, should i re wire them to pull, or just re wire them to come on at a temp like factory??
I would take them back to stock because thats how toyota and every other automaker designs those fans to function. They do that for a reason and there isn't any reason for them to be on constantly especially at highway cruising speeds. They should only be operational when you are in the city in a lot of stop go traffic.
 

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sg1mr2 said:
my two and i were making a trip about 40 miles to my new home i am currently moving into, about 39 miles into the 40 mile trip i looked down and saw my temp Gage at H. i quickly pulled over and shut down. i could hear the coolant boiling. my heart sank, i waited a while and tried it and the car started fine but i shut it off and pushed it home anyway.

i have used the search and read other peoples stories and the help offered them.. What should i do first.??

i bled the coolant about a month ago when i was having high rpm troubles.


Where should i start? t-stat?replace coolant?i guess tomorrow morning ill check the oil to see if there is any coolant present and pray my HG is intact.
and help would be very greatly appreciated... :notworthy
Oh, one more thing ... wouldn't help you now but at least maybe someone else will read it ...

If you are driving and notice the coolant temps higher than normal, pull over, but _do not_ shut the engine off. Turn the heater to "H" and then let it idle for a while. More likely than not, the temps will slowly come down. Once down, then shut off. You don't want to shut-down on a overheated engine ...

Cheers,
8j2_93t
 

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Good point about shuting the engine down following a temp problems. Could save some big $$.

Another thought to try is drain the coolant, checking its colour, etc and then refill with a special anticorrosion additive or radiator flush (not antifreeze). Run this through a few times with the engine going and then flush again. You may have a corrosion problem in the radiator/lines/heating core/engine and this will help free-up any deposits including the thermostat. When you drain again monitor what comes out and make your decsion from there on what to do. I've seen alot of thermostats get replaced when they are only the symptom of another problem.

Hope that this helps.

Jim
 

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Not to say that it is a head gasket, but when mine went, it was an 8-month affair that started by randomly overheating on the highway. 5000 miles later, it overheated again. 5000 miles later it barely made it back from Amarillo to Tucson, and I warped, cracked and destroyed the head.

8J2_93T said:
_do not_ shut the engine off
I think that kind of depends. If it's just running hot, taking the load off the engine and running it at 2K or so seems to help tremendously (I've had better luck at 2K than idle--I think the extra water pump flow more than offsets the extra heat production). If it's pegged, I usually rev it good, then shut it down. Wait a little bit, turn it on, rev it good, then shut it down. Leave the key in the on position so your fans are blowing, and set it to heater if it wasn't already.

Someday, I want to get a temp gauge that goes to 400 degrees, so I can actually see which reduces temperature faster (and without heat soaking to 500 degrees). Also, I want electrical oil and water pumps so I can be pumping cool oil/water without adding heat through engine combustion.
 

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PETC said:
I'd remove the coolant and check the thermostat. That's probably the most likely culprit.
Why would you remove the coolant? You do not need to drain the system to check the t-stat. Draining the coolant is useless and a waste. If anything he should BLEED the system to rid it of any air pockets.
PETC said:
You'd have to have a really big HG problem to overheat because of it I'd think...
Not necessarily.
 

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definitely re-wire those fans so they are only on when they are supposed to be. it does absolutely NOTHING for them to be wired in that way.... ( i know you didnt do it! :) )
 

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Does anybody actually know how to re-wire them "properly"? Both of my cars have always-on fans, and that's after I replaced all the sensors, relays, switches and whatnot that appeared to be related.

It doesn't really hurt the car that much, unless it's really cold outside (I'm from AZ, so it's not a huge deal), so I've never bothered to fix it. The worst part is that it's noisy.
 

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Dijital357 said:
definitely re-wire those fans so they are only on when they are supposed to be. it does absolutely NOTHING for them to be wired in that way.... ( i know you didnt do it! :) )
It's not a dire thing that needs to be done. Basically the only thing that happens is it wears the motors out faster on the fans. Unless they are in fact wired backwards and are pushing instead of pulling which i do not think that it's possible. But none the less, what the P.O. did was just wire around the temp sensor that triggers the fans once the radiator gets to a certain temperature. I have never taken a look at this but I am sure there is something about this in the BGB.
 

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^^ you're right, its not a dire thing that needs to be done...but it really does nothing. this is why we have a thermostat. the fan can run all it wants, but if the thermostat isnt circulating the cooling water...well, it's just gonna be running for no reason!

it would be pretty easy to make the fans push instead of pull (dunno why anyone would want this), just flip the wires. they're DC motors...they will run backwards or forwards. definitely check that out.

his PO probably just disconnected the sensor...if you disconnect it, it'll run all the time.
 

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Discussion Starter #14
well checked the t-stat today opened promptly at about 185 degrees. also i checked the oil (no coolant present) and checked the coolant (no oil present). so i am guessing the hg is still ok. also i noticed the coolant was a horrible corrosion brown color. any thoughts?
 

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Discussion Starter #15
also the overfill tank outlet hose(the one that runs the overflow to the ground) is missing so the coolant just sprayed all over the darn place when it did overheat. now i have a lovely mess to clean up.

would the a/c condensor inhibit air flow to the radiator. i have no ac so i guess i should remove it to help some huh??
 

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Horrible corrosion brown color = you have a 15 year old car with rust and stuff built up inside the cooling system. You can flush it out all you want and it will still come out brown a year from now. Eventually, it will clog things up (like your radiator), but it's usually not a problem.

Yes, you can remove the A/C condensor, but the car should work fine with it on still. Unless you're running 30 lbs of boost and really, really need to reduce heat, the stock setup was designed to work with the condensor attached. :p

One more edit: it's possible to eat so many rocks and sticks and other pieces of debris to completely clog the condensor, especially if you live on a dirt/back road, but I've never had any problems with it.
 

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Discussion Starter #17
also i am sure thats a good 20 lb diet for the car i know the ac compressor i removed today was a good 20, also i guess ill be selling a good compressor soon, maybe the cash will help me try and buy a new non rusty radiator.
 

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I would say bleed the system again because it sounds like you have air in the system still. Possibly even have it flushed. Change the oil and filter as well and make sure everything is in top order and just keep an eye on everything and regularly check the two fluids for abnormal conditions and also make sure the gauge stays where it is. You may want to, just for the hell of it, replace the t-stat because they are cheap and easy enough to replace, so it wouldn't hurt to change.
 

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Discussion Starter #20
So, i guess ill flush the radiator by removing it completely, during which ill remove that pesky ac condenser. then ill flush the coolant system as best i can, maybe unhook the heater core and flush it also. then change t-stat, then refill and bleed coolant. then change oil and filter again., anything else you can think of to help my situation? i think i will replace that hose from the overfill tank just in case so i don't give my engine a coolant bath if it happens again. Any more thoughts? thanks a million for the help.
 
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