Overheating question

[BruteForce]

Ok, it's overheating. I put in a new fan clutch. The symptom is the top hose and the top of the radiator get too hot to touch, while the bottom of the radiator and bottom hose remain lukewarm.

Is that the thermostat failing to open?

[quagmire]

No, that part is normal.  It usually means the radiator is doing it's job, probably the thermostat too.  The upper hose is the radiator inlet, and it should be significantly hotter.

[BruteForce]

Yeah, but then it shouldn't be overheating? This is at idle.

[quagmire]

Depends.....  If the thermostat isn't opening enough the coolant may still run hot in the engine itself.  It could have an air pocket too.  When did it start?

[BruteForce]

Well, I've just gotten it running. Poured water in and started it, let it heat up then cool down. Refilled the rad and then started it again. Once it cools down I'll check the water level again.

[quagmire]

Probably an air lock then.....  Sometimes jacking up the front end helps the bubbles work their way out easier.  You could also pop out the thermostat and fill the radiator till the coolant reaches the top of the water neck area, them reinstall it and continue filling.  Doing those two things will pretty much eliminate any air bubbles.  Mine had a ton of air in it the first time I fired her up. 

[moparniac]

just take the rad cap off while the car is running and let it get up to temp to burp out the airpocket,,,

[BruteForce]

I shall attempt running with the cap off first, as it is easier. If that fails, I'll pull the thermostat. Thanks, guys!

[dodj]

I shall attempt running with the cap off first, as it is easier. If that fails, I'll pull the thermostat. Thanks, guys!

Have a mop handy. I think the 'no cap' method is best but when I did it, at some point of the engine heating up, the water came up and out the top. Got rid of the air though.

[BruteForce]

Ok, I jacked up the front about 8 inches, pulled out the water temp sensor plug, filled it, put the plug in, filled the rest, and now the temp stabilizes at the higher end of the normal range on the factory gauge (whatever that means) so I suppose it's all right.

I drove it around the block for the first time in 5 years, that was quite a thrill.

But it seems to be burning oil a bit