Working on the hotter side

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

jvazquez53

El Tractor
Joined
May 6, 2007
Threads
352
Messages
3,413
Location
San Juan Puerto Rico
Website
www.facebook.com
I'm running out of ideas, as you can see in the picture, that's the temperature on my truck after a 20 minute highway drive, no thermostat (with thermostat almost hits th H), radiator was professionally cleaned, no air bubbles, no heater. The water pump seems Ok from the outside, no noise, no leaks. Is it possible for the pump to be defective, ex. impellers? Anyone had this problem?
DSC00018.webp
 
Have you checked the temp with any other method...digital themometer or? I experienced the same issue, but the problem was the gauge.
 
I don't trust professionally cleaned radiators...... and yes, water pumps wear out ......
 
water pump

It may be the water pump. I changed mine out just so I new when it was installed and to eliminate one problem that could raise its ugly head in the wrong place, and the needle does ride a little lower on the gauge. :hhmm:
 
Last few things I have done: Put fan clutch grease, tried another gauge, remove air from the system, checked the water pump (removed the top hose and started the truck; water gushed all over), and still running hot according to the gauge. One thing I noticed is the pressure built by trying to squeeze the top hose. Isn't supposed that when the thermostat opens, the pressure on the top hose is relieved? BTW I did tested the thermostat it opens at 90 degrees.:mad:
 
get a real temp gauge

And the tstat opened at 90 or 190*??
 
Got another gauge and the thermostat opens at 190 degrees.
 
Head Gasket is split BETWEEN two Cyls. You won't get any oil/water mix but your temps will run hot and eventually you will start completly overheating after 20-30 minutes of HWY driving. Exact same thing happened to my first FJ60.

Hopefully this isn't it, but it has the EXACT symptoms mine did...

GL
 
As others have said, verify that your temp gauge is accurate.

If you're running hot, it's because either your cooling system has a defect or you have a pressure leak.

I'd start by verifying that the system is pressure tight because it's one test and it's very straightforward. If you don't have a radiator pressure tester and don't want to buy one, any decent mechanic or radiator shop should be able to do it.

If you have a pressure leak, oh crap. If you're system is pressure tight, then keeping loking at cooling system components.

Running without a thermostat is not a problem in Puerto Rico.
 
a compression checker will verify a popped head gasket easily.
 
As Zulu said -- Check your compression. Check your timing. Seems like you've checked everything else.
 
Got another gauge and the thermostat opens at 190 degrees.

Another used toyota guage or a mechanical guage. If you just traded guages then its may still be a ground problem. You need to hook up an mechanical guage see what the temp is. a picture of your gauge means nothing. 191 deg or 220 deg means something. I have seen people chase this all over the world just to come back to a bad guage.
 
Another used toyota guage or a mechanical guage. If you just traded guages then its may still be a ground problem. You need to hook up an mechanical guage see what the temp is. a picture of your gauge means nothing. 191 deg or 220 deg means something. I have seen people chase this all over the world just to come back to a bad guage.

Agreed, well put... Definately make sure the temp gage is working first
 
I used an electric gauge that went all the way to 240 degrees, I used separate ground, everything isolated from the OEM gauge. Ok... assuming that the gasket needs replacement, on a scale from 1 to 10, how hard is to replace? :eek:
 
So what is the reading on the gauge you used. All I have seen is a picture of the toyota guage at the high end. How hot is your truck running?
 
230-240 degrees.
 

Users who are viewing this thread

Back
Top Bottom