I just had my radiator hoses replaced, and a new thermostat installed about a month ago. Anytime i drive in the heat (65^) my engine begins to overheat.

I seem to be putting in antifreeze way more then necessary, and I frequently find the coolant resavoir cap off and lots of pressure coming out of the radiator making the resavoir bubble and steam like crazy.

Someone please help me on figuring out whats wrong, I don't know what to do and I really need my car to drive to work.

Thanks


93 4runner, 3.0 auto

 

Water pump been serviced recently?

 

How old is the radiator ?, it might be time for a new one.

 

pull the bottom hose off the rad open the cap and run the garden hose in it, flush it and see how fast it flows.

 

Did you check the thermostat by drop-in it in hot water.?

 

Go start it up with the radiator cap off.....rev the motor...does it shoot water
out of the spout? If it does you have a blown headgasket. Try that first.

 

If the radiator was drained and it looks to have been replaced in the last few years.

The over heating started before you changed anything?? How hot did it get the head gasket could now be toast.

Did you see any big clouds of white smoke?? Any problems with coolant and oil mixing

I would think of a air pocket does your temperature gauge get hot or does it just push out coolant .

Could be a air pocket which will push out coolant. A pressure tester is good at times like this could just be a clogged worn out radiator

 

hm.

well when my '86 was doing that.....it was Blown Head-Gasket.

not trying to be negative...just sayin lol

 

A blown head gasket is nothing to laugh at I'm afraid. My first Runner blew the gasket inside a month, cracked the head in three places and warped the block. If you're still driving that around park it quick and get it checked out. If it sounds like a coffee maker under the hood, the pressure is all messed up from the bad gasket. Check by the firewall and make sure there's no antifreeze going out the back side of the block and winding up on the tranny case. Otherwise, when it goes, it'll go in a blaze of glory. Good luck

 

bad fan clutch ?

 

bring it up to temp and feel all around the radiator (from the front) for any cool spots. it is likely the cool spots are blockages in you radiator (mud). it will not effect you rolling around town, because your radiator is not 100% used, but when you put the engine under a good amount of stress (climbing a mountain pass), your thermostat will rise quickly. i say replace the radiator.

 

did you install the thermostat or did someone else ? i had a nissan that would blow the lid off the over flow bottle. it turned out the thermostat did not have a relief valve in it ,which would cause a pressure built up. if it started after the repair work ,it would be worth looking at.

 

replace radiator cap and fan clutch, if that doesn't do it then test then radiator and water pump

 

I've also seen an air pocket cause problems. Me and a bud of mine swapped a straight six in a ford 100 and it started running hot, heater would not come on etc... had to take a heater hose off to escape the air.

 

Check that your radiator isn't clogged, possible stop leak buildup from a previous owner?

Verify that thermostat is working propoly, or just replace it, they aren't that expenisve.

 

My solution was pressure testing the cooling system to find out that my rad top tank had 11 tiny cracks that allowed air to enter and cause air pockets but never leaked coolant till I did the pressure test and it even took about 30 sec to reveal the tiny cracks with the coolant seeping out very slowly.

 

Better to find out the problem before changing a bunch of parts that doesn`t fix the problem

With out a pressure tester you are limited to what you can check

 

almost anything cooling system related is worth changing after 100K+ miles
most of it isnt too expensive, easy to replace, will add years to the motor if you do it before it starts to overheat
and doing it now is invaluable if you're truck starts to overheat as you're the best man at a wedding and 1/2 way there the car hits 250* lol

 

Bought a new thermostat today, about to order a new radiator.

A shop tested the radiator and said it was fine, installed a new thermostat and hoses and rad cap and it ran better for about 3 weeks although came very close to overheating.

Note: The radiator was pressure tested, but it dosen't even look like it came with the car.

**Any suggestions on what radiator to get? Aluminum seems like the way to go but this site also looks good https://www.radiatorbarn.com/

 

Finally got my new radiator shipped, replaced the thermostat and brand new 3 core alum radiator.

So far so good, runs MUCH smoother then the old stock radiator.
Now to start fixing the other problems()

Thanks for all the help