Truck runs hot over 60kph? dunno why?
- Thread starter OzzyNF
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echo4tango
New member
have you replaced the coolant and verified the correct temp. thermostat was put in.
brian2sun
Elite Member
Do you mean it only has water in the cooling system right now?... no coolant? If so, that is very bad. Water will rust and corrode the internals, eat through your head gaskets and ruin your engine quicker than you might think.
Qyota
New member
ER, not really. While coolant has a higher boiling point and does provide some protection to cooling system components, running distilled / deionized water won't do what you're saying it will. It will freeze (not good), and it will not cool as effectively (also not good), but it won't "eat your head gaskets" or ruin your engine.
echo4tango
New member
Either the dash guage is not working correctly..or the new thermostat is the wrong part . I would for sure drain the water and replace with COOLANT and see if that helps. keep us updated on the problem
brian2sun
Elite Member
Er, yes. Running straight water with no coolant causes rust and rust eats through head gaskets and lots of other components and it does not take very long to do it. I've seen it happen specifically to Toyota 3.4s. The lack of coolant is almost positively what's causing you to overheat too - water has a much lower boiling point than coolant and that = hotter running temps. Stop neglecting your cooling system.
Qyota
New member
You do realize that "coolant" is mixed 50/50 with water, right? What's the head gasket made of, iron? I agree that straight water is not ideal, as it will allow some corrosion and (as mentioned) will freeze and boil, but it isn't certain death for your engine. I run straight DI water in my track bike, since we can't have coolant on the track.
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brian2sun
Elite Member
Yeah, I'm aware that you mix the water and coolant 50/50, but it's that 50% of the coolant that makes the difference when you're talking corrsion.
Are you aware that the HGs on a 3.4 are paper and metal?
004Gunner
New member
I think Qyota is referring specifically to distilled water vs garden hose water. If that's the case then yes, distilled water would have far less negative effects on iron as compared to tap water. I think coolant usually has some protective additives too like rust inhibitors (lmgts). Either way, I agree the OP should be running a 50/50 mix of coolant and distilled water before trouble shooting anything else.
OzzyNF
New member
the thermostat is the right part for the truck...i will replace the water with 50/50 coolant but I don't think it will make a difference. I was a little worried that I may have a cracked head or something. She does not overheat in city driving.
I was also thinking it may be the cooling sensor. Yes, the guage is working correctly.
I was also thinking it may be the cooling sensor. Yes, the guage is working correctly.
echo4tango
New member
I dont think its a head issue because you would notice oil all down the side of your block.. Something is not allowing the thermostat to open up and pump cool fluid into the block and thus causing an overheating issue.
One possible reason a car for overheating is that antifreeze is not circulating through the engine as it should such as a bad thermostat or plugged hose.
Antifreeze serves two purposes. It not only keeps the engine temperature level during the winter (preventing the engine from freezing) , it also keeps cars from overheating during the warmer months
Don't just look inside the plastic overflow bottle- remove the radiator cap (when the engine is cold) and look inside the radiator. You should be able to physically see the fluid level if it is at its proper level.
If water is the only thing that has been used then it is possible rust and water calcification could have accumulate in the radiator and drastically reduce the flow of coolant at high speeds.
The only way to fix calcification from a car being run without coolant is by removing the radiator from the vehicle for disassembly and cleaning or radiator replacement
One possible reason a car for overheating is that antifreeze is not circulating through the engine as it should such as a bad thermostat or plugged hose.
Antifreeze serves two purposes. It not only keeps the engine temperature level during the winter (preventing the engine from freezing) , it also keeps cars from overheating during the warmer months
Don't just look inside the plastic overflow bottle- remove the radiator cap (when the engine is cold) and look inside the radiator. You should be able to physically see the fluid level if it is at its proper level.
If water is the only thing that has been used then it is possible rust and water calcification could have accumulate in the radiator and drastically reduce the flow of coolant at high speeds.
The only way to fix calcification from a car being run without coolant is by removing the radiator from the vehicle for disassembly and cleaning or radiator replacement
024RunnerSE
New member
I wouldn't run anything in my cooling system except the pink stuff. No straight water for me. I've already been through the horrors and i'm with brian2sun on his theory. You should pull your radiator out and have a shop check to see if its clogged.
fusedapart
New member
I had the same problem with my 2000, had the fan clutch checked, replaced hoses, thermostat, and cleaned out the radiator.
I am now stuck with 2 options: I heard that moving the transmission cooler out of the radiator can help OR replace the water pump because the fins can become corroded.
I am now stuck with 2 options: I heard that moving the transmission cooler out of the radiator can help OR replace the water pump because the fins can become corroded.
TheDurk
Elite Member
This is actually not exactly true as stated--if you mean the temperature of the coolant with just water will be higher than with coolant. Pure H20 has a higher thermal density than ethylene glycol and thus sucks more heat out of the engine. It is a better 'coolant'. What does happen is that the lower boiling point means you will boil over sooner. Steam is a terrible coolant and the metal in the engine will get extremely hot and bad things happen quickly.
Certainly he should run ethylene-glycol based coolant for that reason and for the anti-corrosion reasons. But it will probably not fix his problem as there is no indication of boiling over. I am not sure why he doesn't boil over, however.
I'm leaning toward clogged radiator or WP issues, possibly due to non-use of coolant, especially if there is any mineral content in the water used.
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