Overheating After Replacing Timing Belt And Water

[Jacob]

Hello everyone,

I have just finished replacing my timing belt and water pump and the car is now overheating. It happens as soon as I start driving, even at very low speed. When I finished the timing belt job I added antifreeze to the reservoir and then started the engine and it seemed that the antifreeze level didn’t drop. Could it be the thermostat or the water pump? The overheating is so bad that I can’t drive to the nearest dealership.

My car is 96 LS400

Thank you for your help

Jacob

[flash213]

Is this the first timing belt youve done?Is there cooloant leaking? Did you put in a new thermostat? How much coolant did you add? Might want to consider towing it in to a mechanic.

[95LS400Bob]

If there is a radiator cap on the radiator..remove it and check the level in the radiator. Lot of times coolant tank won't fill the radiator if really low. I don't know if Lexus has a cap on the radiator or not but most cars do.

[Jacob]

Is this the first timing belt youve done?Is there cooloant leaking? Did you put in a new thermostat? How much coolant did you add?Your belts are on correctly? Might want to consider towing it in to a mechanic.

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Yes this is the first time I do a timing belt and I wish I didn't. I put less than a gallon of antifreeze, and I don't see any leaks, and I didn't replace the thermostat because it was replaced about a year ago (aftermarket).

would over tightening the water pump bolts cause such a problem?

Thnak you

[Jacob]

If there is a radiator cap on the radiator..remove it and check the level in the radiator. Lot of times coolant tank won't fill the radiator if really low. I don't know if Lexus has a cap on the radiator or not but most cars do.

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There is no cap on the radiator, and I only put coolant in the tank not in the inlet by the engine. could this be the reason?

[flash213]

I think youre in need of more coolant. You should be adding 50% toyota coolant and 50% distilled water. If I remeber correctly it should roughly take two gallons.

[Jacob]

I have just added 3 quarts of coolant to the water filler inlet and took the car for a test drive and within less than 2 minutes it reached the red mark on the temp gauge. I then parked the car and looked the coolant tank which was empty. As I tried to remove the cap, coolent rushed into the tank and filled it in a matter of 3 seconds.

What do you think is my problem? :cries:

Thank you

[sha4000]

it should take almost 3 gallons to fill the engine,radiator and reservoir after i changed the timing belt about 2 and a half months ago my cars temp gauge starts to rise when i turn the a/c on but only when its 90+ outside and i still havent figured it out someone told me the new belt might be putting too much pressure on the old pump but everything was ok until i did the TB job since then i even flushed the cooling system and put a new thermostat and still no luck what do you guys think?

[flash213]

Its normal for the coolant level to rescede in the tank after running the engine on a refill. Stop driving the car and let it just run in your driveway. Again add distilled water and coolant 50/50.

[Jacob]

So many thanks to everyone

I have just solved my stupid problem which was nothing but very low coolant… a stupid mistake that could have cost my big money.

[RFeldes]

sha4000 are you still having problems? If so, after all you have done I would suspect the water pump or a clogged radiator. By clogged I mean cleaning the fins.

There are posts here on the procedure.

[Lexusfreak]

So many thanks to everyone

I have just solved my stupid problem which was nothing but very low coolant… a stupid mistake that could have cost my big money.

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It happens. I just hope no damage was done. Good luck! B)

[Jacob]

So many thanks to everyone

I have just solved my stupid problem which was nothing but very low coolant… a stupid mistake that could have cost my big money.

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It happens. I just hope no damage was done. Good luck! B)

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Everything sounds fine... Thanks god it's not a Nissan :D

Thank you

[sha4000]

sha4000 are you still having problems? If so, after all you have done I would suspect the water pump or a clogged radiator. By clogged I mean cleaning the fins.

There are posts here on the procedure.

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yeah man its really getting on my nerves i never had this problem until i changed the belt everything else is fine so im inclined to thinkit might be the pump the only thing that i cant figure out is why it only happens when i turn the on the a/c on a really hot day. has this happened to anyone else?

[jadecuir]

sha4000 are you still having problems? If so, after all you have done I would suspect the water pump or a clogged radiator. By clogged I mean cleaning the fins.

There are posts here on the procedure.

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yeah man its really getting on my nerves i never had this problem until i changed the belt everything else is fine so im inclined to thinkit might be the pump the only thing that i cant figure out is why it only happens when i turn the on the a/c on a really hot day. has this happened to anyone else?

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When you did the timing belt, did you pull the radiator and clean it and the AC condenser? Are you sure your coolant level is OK, and the engine chambers free of air? It takes quite a while to bleed all the air out of the cooling system. It should be done with the heater on high, so all the air is out of the heater core.

Did you maybe disconnect the electric fans when you did the job? Are they coming on when it overheats? Are all the temp sensors plugged in?

[sha4000]

i cleaned the radiator out but i never removed the condenser, my coolant level is fine.how exactly do you bleed the system?i did turn the heater to hot and let it run for a while.my cooling fan comes on as soon as i start the car and the condenser fan comes on as soon as i turn the a/c on and all sensors are connected.how can i check to see if the fan clutch is operating correctly?like i said this only happens when i turn the a/c on when its really hot outside