Air pockets in Cooling system

[SMB]

Good day all, and sorry for the long post.

I am trying to diagnose a problem with my friend's 00 Camry I4.

The engine will overheat only at idle but after 7-8 seconds the fans will kick in and the temp will go down. This problem will occur intermittently sometimes after a 100 mile drive or a 1 mile drive.

I have the same engine in my Camry and it never does that.
All switches and sensors are working properly.

Now i am thinking since he replaced the radiator a few weeks back therefore there might be some air pockets still trapped inside. I don't think he purged the system yet.

The heater will blow warm air at idle but once the car is on motion, the heater works perfectly. before radiator replacement, the heater works all time at idle and in motion.

My question is could the air pockets cause this overheating incident?

Thanks in advance.

SMB

 

[c3po]

Yes it can, did your friend leave the radiator cap off while the engine was 1st started after the radiator replacement.

Some cars like my 04 Marauder have some sort of a vent cap in the coolant hose.

Your friend needs to get that air out.

 

[oilboy123]

Some cars are hard to bleed. Sometimes you have to drive aggressively to get the water pump to push the air out of crevices.

Some cars like c3po says have vents that bleed out the air when filling coolant. Don't know if it applies to the Camry?

 

[c3po]

I am wondering if air in the cooling system can put pressure on the:

1) Hoses
2) Radiator
3) Head Gasket

 

[EXPLORER]

You might try jackng the front end up at a pretty good angle, run with the radiatot cap off at a least 1000 r.p.m. for a good while at operating trmperature, kind of like burping the system, worked for me in a couple situations with trapped air.If the coolant level drops then fill, and dont forget the puke tank. Good luck

 

[c3po]

Originally Posted By: EXPLORER
You might try jackng the front end up at a pretty good angle, run with the radiatot cap off at a least 1000 r.p.m. for a good while at operating trmperature, kind of like burping the system, worked for me in a couple situations with trapped air.If the coolant level drops then fill, and dont forget the puke tank. Good luck



That sounds like excellent advice since you want the radiator cap to be the highest point in the cooling system.

On my small block chevy I drilled a very tiny hole in the thermostat too let any air escape if it is trapped inside the engine.

 

[SMB]

Thank you all. I don't think he purged the cooling system yet. These engines don't have a bleed valve but a small jiggle valve in the OEM thermostat for air to escape. He has an aftermarket Stant SuperStat installed.

I will try to remove the air pockets myself. There is a good steep incline I know of that should do the trick.

I'll update you all on what happens, if any!

 

[SMB]

Well I removed all the air from the cooling system and the heater is still not working properly for some reason.

I know the coolant was brown in color before we changed the radiator and now it's brown again. I think a good flush is in order.

Is there a way I can find out if the heater core is clogged? Like touching the hoses or something like that?

Remind me, if the thermostat is working properly, the upper hose should be hot and the lower hose should be normal (not cold) to touch right?

 

[c3po]

Upper hose should be hot, so the thermostat is probably fine.

This thing needs to be flushed.

You might need a new heater core.

In order to flush this system out, you need to do some things:

1) Drain coolant
2) Take thermostat out
3) Fill system with water
4) Disattach upper radiator hose
5) Have 10 to 20 gallons of water ready
6) Attach a hose to upper radiator hose going into a bucket
7) Start the car
8) Keep adding water until it is clear coming out.