Overheating situation

[albertliang3]

Hi guys. I just replaced my steering rack today. I took off my whole radiator assembly. But after everything put back. My water temp went to the top. I quickly shut off the car and put more water in the radiator. Everything seems works fine. However I was waiting a train to pass. The temp slowly raise while engine is on and in park. Will a coolant bleed help in this situation?

Thank you guys

 

[BullElk]

Whooaaa. That is hot. By the time the needle moves a micronanagram…. It’s tooooo hot.

A good burping may be the issue.

 

[Trunk Monkey]

Likely you have an air pocket in the system. Not the best way to get it out but park on an incline and see if the bubble goes to the front. Better is to get a collant fill kit, pretty sure auto parts places loan, that pulls vacuum on the whole system.

 

[BullElk]

^^^^^

 

[2001LC]

With low coolant level. We typically see coolant temp gauge, read low. This is because, the water temp sensor is out of the coolant in an air pocket. It's then only reading air temp in the void/pocket. The air is nowhere near as hot as the engine block, heads or coolant within them. As the coolant heats, it expands. As it expands, it may then, get to level of coolant temp sensor. At that moment, the coolant temp gauge goes up. If it goes above normal as yours has, it's very hot. Your not in red, that good we "hope". "Hope", since coolant may be barley touch sensor, so you could be red lined. Redline for more than a few minutes, risk blowing head gasket and or warping heads.

I use the same procedure every time to top coolant, without and special tools:

1. Fill the system with Toyota coolant, either LL "red" mixed 50/50 with distilled water (98-03), or SLL premix "pink" (04-up). Filling reservoir too, to full line.
2. Run engine until operating temp reached, squeezing upper radiator hose multiple times during warm-up. Bring RPMs up to 3K for a few minutes, after warm-up. Turn off engine, with vehicle level. Or even better, with front of vehicle higher than rear, which put high point (air bubble) at radiator cap. Then let cool 8 hours.
3. After cool down, remove radiator cap, and top with coolant. Run engine to op temp again, getting up to 3K RPM before shutting down, to cool down.
4. Again check coolant level under the cap, after 8 hour cool down.
5. Repeat after each cool down. Until radiator found full (no coolant needed), to the neck (bottom of cap).

Notes:

• With cabin heaters on full hot, heat should blow very hot when coolant system full. If not blowing hot, coolant level is low. If coolant level not low, air bubble is in heater core(s). A short drive after topping with hard braking, usual moves the air bubble out off heater cores. Repeat topping procedure.
• Coolant is very sensitive to temperature. The reservoir after cool down will be near full line if OAT (outside air temp) high, say 100F. It will be at low line if OAT very low, say -10F. Checking coolant level under radiator cap, should be done at coldest time of day, before sun-up heats the air. Radiator should always be full. But reservoir level will vary by temperature of coolant. So if radiator actually a little low, and you check during heat of day or before engine cooled down. You'll get a false full, and often fluid comes out the radiator as cap removed.
• Never remove cap when engine hot. Hot coolant, will blow out with force.
• Removing radiator cap before full cool down, looses vacuum created by cooling (contracting) coolant. Then system will not function properly.

A number of mistakes are made with coolant system by many INDY shops, DIYers even Dealerships.

• Leaving air in the system.
• Wrong, bad or improperly installed thermostat.
• Bad radiator cap.
• Forcing reservoir hose in, curl it up on side shelf. Result in sucking air into radiator.
• Not checking reservoir hose & cap for obstruction.
• Not cleaning radiator fins on a regular basis.

Radiator fins need cleaning! Alert Alert Alert

I've a 06LC w/192K I just bought. In reading history I found PO complained of engine temp raising when both front and rear AC on. Toyota Dealership diagnosed with clogged radiator fins. Recommended new OEM radiator, $600 for the US spec Radaitor plus coolant and labor. They should have added...

forum.ih8mud.com

Just a few reservoir hose & cap pic. Not specific to OP issue.
Curled up res hose

Plugged res hose and cap.

 

[OEMGUY0720]

If the temperature goes up when you’re idle and it drops to normal operating temperature when you start to drive, it’s likely your fan clutch.

 

[2001LC]

Fan clutch a good guess, and certainty possible if not engaging (can happen). But when they fail, they tend to lockup producing air flow at all times.

We've no idea why, he pulled radiator, since not needed to replace steering rack.

But since radiator out only mention, and no mention overheating before. Points to improper topping.

 

[albertliang3]

With low coolant level. We typically see coolant temp gauge, read low. This is because, the water temp sensor is out of the coolant in an air pocket. It's then only reading air temp in the void/pocket. The air is nowhere near as hot as the engine block, heads or coolant within them. As the coolant heats, it expands. As it expands, it may then, get to level of coolant temp sensor. At that moment, the coolant temp gauge goes up. If it goes above normal as yours has, it's very hot. Your not in red, that good we "hope". "Hope", since coolant may be barley touch sensor, so you could be red lined. Redline for more than a few minutes, risk blowing head gasket and or warping heads.

I use the same procedure every time to top coolant, without and special tools:

1. Fill the system with Toyota coolant, either LL "red" mixed 50/50 with distilled water (98-03), or SLL premix "pink" (04-up). Filling reservoir too, to full line.
2. Run engine until operating temp reached, squeezing upper radiator hose multiple times during warm-up. Bring RPMs up to 3K for a few minutes, after warm-up. Turn off engine, with vehicle level. Or even better, with front of vehicle higher than rear, which put high point (air bubble) at radiator cap. Then let cool 8 hours.
3. After cool down, remove radiator cap, and top with coolant. Run engine to op temp again, getting up to 3K RPM before shutting down, to cool down.
4. Again check coolant level under the cap, after 8 hour cool down.
5. Repeat after each cool down. Until radiator found full (no coolant needed), to the neck (bottom of cap).

Notes:

• With cabin heaters on full hot, heat should blow very hot when coolant system full. If not blowing hot, coolant level is low. If coolant level not low, air bubble is in heater core(s). A short drive after topping with hard braking, usual moves the air bubble out off heater cores. Repeat topping procedure.
• Coolant is very sensitive to temperature. The reservoir after cool down will be near full line if OAT (outside air temp) high, say 100F. It will be at low line if OAT very low, say -10F. Checking coolant level under radiator cap, should be done at coldest time of day, before sun-up heats the air. Radiator should always be full. But reservoir level will vary by temperature of coolant. So if radiator actually a little low, and you check during heat of day or before engine cooled down. You'll get a false full, and often fluid comes out the radiator as cap removed.
• Never remove cap when engine hot. Hot coolant, will blow out with force.
• Removing radiator cap before full cool down, looses vacuum created by cooling (contracting) coolant. Then system will not function properly.

A number of mistakes are made with coolant system by many INDY shops, DIYers even Dealerships.

• Leaving air in the system.
• Wrong, bad or improperly installed thermostat.
• Bad radiator cap.
• Forcing reservoir hose in, curl it up on side shelf. Result in sucking air into radiator.
• Not checking reservoir hose & cap for obstruction.
• Not cleaning radiator fins on a regular basis.

Radiator fins need cleaning! Alert Alert Alert

I've a 06LC w/192K I just bought. In reading history I found PO complained of engine temp raising when both front and rear AC on. Toyota Dealership diagnosed with clogged radiator fins. Recommended new OEM radiator, $600 for the US spec Radaitor plus coolant and labor. They should have added...

forum.ih8mud.com

Just a few reservoir hose & cap pic. Not specific to OP issue.
Curled up res hose
View attachment 3506723
Plugged res hose and cap.
View attachment 3506718


View attachment 3506719

Great write up. I’ll go ahead do that. Thank you very much

If the temperature goes up when you’re idle and it drops to normal operating temperature when you start to drive, it’s likely your fan clutch.

But the fan clutch seems good when I spin it with my hand when truck turned off