Over Heating =(

[NakedAssaultGerble]

Been dealing with an ongoing issue since putting a new motor in the car, it slowly overheats, turning on the heater slows it down but doesn't fix it.

I have replaced the thermostat, the radiator and bled the system multiple times to no avail. I have already taken it to a shop they leak tested the system and checked to make sure my head gasket wasn't blow but couldn't figure out why it keeps overheating.

[Jaxx_]

rolled up newspaper in your radiator fan when it's warm. if you can stop it you need a new fan clutch.

[jlevie]

When does the engine overheat? At speed or only when idling or in stop and go traffic? If only when at idle a bad fan clutch is a good possibilty. But if the fan clutch is good, with a new radiator and themostat in the car and the cooling system properly bled, overheats would be most likely the result of a head gasket leak that is pumping air into the cooling system. A field check for that is to fully bleed the cooling system, drive the car until you see the temp sart to rise (but don't let it get above 3/4 on the gage), and rebleed. Release of a significant amount of air then is evidence of a head gasket leak or a cracked head.

You can properly bleed the system by what is below, but a vacuum fill system is better.

1) Using ramps or a jack get the front of the car 1' or more higher than
the rear. That will make the radiator and bleed screw the highest point
on the engine and facilitate removal of air.

2) With the bleed screw open, add coolant until no more air comes out of
the bleed.

3) Leave the filler cap off, or at least loose, and set the heat for max
temp and fan speed. Leaving the cap loose will prevent air that's still
in the system from causing a "coolant fountain" once the engine heats
up. Start the engine and allow it to warm up to operating temp. As it
warms up occasionally crack the bleed screw to release any air and top
up the coolant as necessary.

4) Once the engine is at temp bring it up to 2000-2500rpm for a few seconds
several times. Then crack the bleed until no more air is released. At
this point the heater should be throwing lots of hot air, which
indicates that the heater core is filled with coolant. You may have to
repeat this a few times to get all the air out.

5) Drive the car a bit, allow it to cool back down, and recheck the
bleed for air. Over the next few days you may get very small amounts (a
few bubbles) of air out of the bleed screw.

[NakedAssaultGerble]

rolled up newspaper in your radiator fan when it's warm. if you can stop it you need a new fan clutch.

Fan clutch is new.

When does the engine overheat? At speed or only when idling or in stop and go traffic? If only when at idle a bad fan clutch is a good possibilty. But if the fan clutch is good, with a new radiator and themostat in the car and the cooling system properly bled, overheats would be most likely the result of a head gasket leak that is pumping air into the cooling system. A field check for that is to fully bleed the cooling system, drive the car until you see the temp sart to rise (but don't let it get above 3/4 on the gage), and rebleed. Release of a significant amount of air then is evidence of a head gasket leak or a cracked head.

You can properly bleed the system by what is below, but a vacuum fill system is better.

1) Using ramps or a jack get the front of the car 1' or more higher than
the rear. That will make the radiator and bleed screw the highest point
on the engine and facilitate removal of air.

2) With the bleed screw open, add coolant until no more air comes out of
the bleed.

3) Leave the filler cap off, or at least loose, and set the heat for max
temp and fan speed. Leaving the cap loose will prevent air that's still
in the system from causing a "coolant fountain" once the engine heats
up. Start the engine and allow it to warm up to operating temp. As it
warms up occasionally crack the bleed screw to release any air and top
up the coolant as necessary.

4) Once the engine is at temp bring it up to 2000-2500rpm for a few seconds
several times. Then crack the bleed until no more air is released. At
this point the heater should be throwing lots of hot air, which
indicates that the heater core is filled with coolant. You may have to
repeat this a few times to get all the air out.

5) Drive the car a bit, allow it to cool back down, and recheck the
bleed for air. Over the next few days you may get very small amounts (a
few bubbles) of air out of the bleed screw.

Overheats no matter what, faster while driving slower while idling. Thanks for the bleeding tips I will give it another go and the shop did the strip test to check for a head issue but I will try the field test as well.

[e30trooper]

change thermostat. you might have a leak

[theevildoodlebob]

I know that this might sound simplistic but is the thermostat installed in the correct direction? I had a new thermostat that wouldn't quite fit into the recess of the housing and I wound up installing it backwards without realizing. Everything fits just fine and tightened up it doesn't leak. When you leave it to idle it will just creep up in temp and if you drive it with the heat on you can just keep it from fully reaching the red but it definitely stays really hot. It also makes it impossible to fully bleed the system as the thermostat isn't allowed to open up and when you open the bleed screw it will always spit a steam/coolant mixture.