Just put a new water pump and radiator in the Belvedere. Filled her up with coolant and started her up and ran for 10 minutes or so. No leaks, but the temp started climbing and the upper radiator hose is full of air. not sure if the thermostat ever opened. Any ideas what the problem is? Thanks for any info (as usual).

 

Ya got some air in there! Some people drill 1/8th hole in the thermostat to help this problem....I never had to. I fill it up and start the car with the radiator cap off, and top it off as the air dissipates.

 

I have a 190 deg thermostat in it that's new. I have a 180 deg that I've been thinking about puttin in....maybe now is the time. I went out and tried bleeding the air out (unhooked the heater hose at the intake and let the air out until coolant appeared). The I started it backup again and ran it for a few minutes. Radiuator tanks and v=coolant in radiator cold.....kept the cap off until.....(GUSH)...hot coolant over flowing ( I'm assuming the thermostat finally opened) hurried and put the cap back on. The Temp guage is HOT. Not sure if this will take care of it. Aren't I supposed to see coolant swooshing when the cap is off? Don't see anything....didn't with my old setup either.

 

Buddy, I just dont TRUST stuff anymore!! A few years ago folks complained about 440 Source water pumps and housings. They said the holes in the housing were too small. There are different vane set-ups on many aftermarket water pumps too. Not always better. I just got a factory t-stat for a Mopar 2.7 motor, the factory one was longer, and MUCH heavier than anything I could get for it from any of the large distributors. I guess what I want to say that you just cant ASSUME that aftermarket is as-good, or better than SOME stock components! Cooling set-ups especially. Those were severely tested by the factory back in the day with big motors, in big cars, in high temps, pulling big loads up big hills!

 

Point taken. I'll have to see how things go once I get all of the air out of the system.

 

Could you have put the thermostat in backwards ? Was it overheating before replacing the water pump ? Did you replace the hoses ?

 

Never took the thermostat out.......wasn't overheating before changing the water pump, although it would get hot if sitting idling for a while.......same hoses.

 

should check that thermostat....

pull it out and put it in some boiling water and see if it opens.

 

It could have a hose collapsing, esp the lower cutting off water flow

 

I'll probably just swap it out with the new 180 deg that I have.

 

Checked that .....seemed fine.

 

When all the air came out of the system did it pull from the overflow, or did you re top off. Also was the car on a flat surface or slant to ensure all trapped air got out?

 

No overflow tank installed (yet).....car was flat.

 

Ok, I had a similar issue with getting air out, and that was due to the top radiator hose was custom made by me to get over belts and to the BeCool radiator which had the opening on the opposite side, believe they wanted an extra grand for the same model with opening on other side.

But the hose was the high point in the system and I had to squeeze the air out of it physically and then the system forced the rest out of it and pulled from the reservoir.

What lb radiator cap do you have, just making sure the system is working as it should to be able to bleed itself?

 

13 lb. cap came with the new radiator. I had a 16 lb. with the old.

 

Well, pulled the 190 thermostat and installed the 180 after I drilled a 1/8 in hole in it. Started it up and ran it for a good 15 minutes......never even got up to temp. Seems like I'm good to go, I'll have to get it out on the road once the weather cooperates to see how things are when driving. I'll keep you posted.

 

Good on ya!

 

I took her out yesterday and everything was good. It's pretty cool here in Michigan right now so the real test will be next summer when we get the 90 degree weather. Thanks for all of the help!

 

End result is that you had a bad thermostat. Good that it is fixed, worst thing you can do is overheat an engine

 

I always change thermostat when i change antifreeze also when bleeding system turn on heat so it bleeds air out also.

 

So it was an aftermarket t-stat? Hmmmm?

 

Not necessarily blaming it on the thermostat guys.......remember, I did have an air pocket and ended up drilling a hole in the 180 that I put in. the 180 was also an aftermarket peice. Never the less, After installing the new water pump, (which was replaced due to a seep hole leak) radiator, and thermostat, all is well.....even at idle!