hey guys, i'm completely new to turbos. I just got this car running and it seems to get hot very quickly, in around 3 minutes under hood temp is very hot. The temp guage says it is fine. I don't have a thermostat in the car right now so it is free flowing. I know turbo underhood temps are higher than normal cars but this just seems way too hot. . And my radiator is boiling. The tailpipe emmisions seem very very hot also. I am afraid to run the car for more than 4-5 minutes because the temps seem to get so high. Any suggestions or am i being too cautious? I am a mechanic by trade for about 5 years so i've been under enough hoods to know around what the temp is there, but I get very little diagnostic training since my shop mainly deals with service, alignments and the like so sorry if this is a noobish question. Thanks for any help guys.
Cooling problems
- Thread starter Firechikin68
- Start date
lonewolf12682;1011274 said:
I checked compression on all cylinders and the lowest was 130 and the highest was 156 on a dry engine that hasn't been started for a couple years. There is no oil in the water or water in the oil. There is nothing pointing toward the head gasket that I can see. But the thought did still cross my mind. I am going to try a cylinder leak down test tomorrow.
tlo86;1011326 said:
No. Like I said i just got the car and all I know about the history of it is the guy I got the car from said the guy he got it from said he thought the timing was way out. So i'm kinda working in the dark as to what has already been done to the car. Whatever has been done was all done backyard. There are nuts and bolts missing in places and you can just tell the car wasn't taken very good care of.
Edit: Also forgot to say the oil pressure guage says I was at 30psi until it warmed up and it goes to about 15-20psi. And like I said the compression checks out and there is no indication of transfer of fluids between the water and oil.
Last edited:
id say bhg definately especially if the water is boiling in the radiator. why dont you go to napa and get one of those coolant testers to check for exhaust gases in the coolant theyre like 50 dollars.
do you have the stock fan or electric? i had an electric and i took a crap on me and my coolant was boiling because the fan wasn't working so i put a stock one on and that solved it. if you have a stock fan then i'd say your probably heading for a rebuild.
Since the thermostat is by far the largest restriction (even when open) in the system if you don't have it installed and the temp gage shows normal you have little to no excess cooling reserve. Assuming it's not the head gasket I'd be checking the radiator for cold spots with an IR gun. Fwiw I always replace the radiator (assuming it's history is unknown) as a matter of course on any car I buy. Imo it's just a wise thing to do.
make sure all air is out of the system and that your radiator cap is working right. And put a thermostat in it. If your radiator cap is not working right it could bleed off pressure too easily, making the coolant boil at lower temps. Also make sure you have a good coolant mix, and do a leak down test with the radiator cap and oil cap off. If radiator level rises/bubbles youve got a crack or head gasket issues. Those compression numbers dont look too good, a difference of 20 psi is usually the max you should have between any two cylinders.
I was told this a long time ago from a competent mechanic, but if its not true someone can dispel the info. I was told that having no thermostat can actually lead to overheating. The theory is that the coolant travels through the system so fast (as its not restricted by the t-stat) that it doesnt get a chance to cool as much while passing through the radiator.
uhh... seems like a silly idea to me. i'll tell you my store about thermostats...
several of my friends needed some work done to there cars, i suggested just taking the thermostat out, since you "dont" need one... well... my friend who commuted to work with about... 15-30mins of driving his car would NOT get hot at all. it was always cold...
and my other friend with an aluminum radiator, an e-fan, and no thermostat... we could barely get his temp gauge to read so his car was always dumping in tons of fuel trying to warm it up... lol.
so i think its for keeping the engine warm, keeping hot coolant/water in the heater core, and then when the engine gets too hot then the thermostat opens and exchanges the hot for cold...
several of my friends needed some work done to there cars, i suggested just taking the thermostat out, since you "dont" need one... well... my friend who commuted to work with about... 15-30mins of driving his car would NOT get hot at all. it was always cold...
and my other friend with an aluminum radiator, an e-fan, and no thermostat... we could barely get his temp gauge to read so his car was always dumping in tons of fuel trying to warm it up... lol.
so i think its for keeping the engine warm, keeping hot coolant/water in the heater core, and then when the engine gets too hot then the thermostat opens and exchanges the hot for cold...
^ That's what I meant about excess capacity. Contrary to popular belief the stock system has some. Easily meets the SAE requirement of a 6% continuous grade on a 100F day with AC and all accessories operating. His car should not be running a normal temp sans stat. Assuming the HG is good it means his system is on the edge. If it tends to overheat with a slight rise in ambient over days it's fine that'd be another indication.
i think he needs to flush the coolant system... and probably clean the radiator (or get a new one)
and how does he know his radiator is boiling? he takes the cap off while its running? lol
and how does he know his radiator is boiling? he takes the cap off while its running? lol
What is the temperature gauge reading? I know it's not the most accurate way of measuring temp (over dampened) but if it's overheating enough to damage the engine, then the needle should move...
I have the same problem, and I'm sick of putting more coolant in all the time. All tests came back normal. Temp needle below half all the time, still coolant boils over. Have new autozone radiator cap. I believe I have a pinhole leak somewhere. That will lower the PSI of the system but keep temps normal. I have UV dye and a UV light, and am gonna check for leaks soon. Try that.
Take no offense in stating the obvious, but has the cooling system been pressure flushed and refilled with brand spanking new toyota red coolant and distilled water?
If not, it could be that the coolant is just old and broken down... it can't stabilize the water anymore.
If not, it could be that the coolant is just old and broken down... it can't stabilize the water anymore.