My 85 is running hot, I've had it for 4 years.It's all stock and I haven't had any problems with it running hot until now. And what I mean by hot is 260 and it has gone to 299 before I got it shutdown. I've removed the radiator and had it cleaned and had new end caps put on it,it has a new cap that was tested,new thermostat that was tested before it was installed,new upper and lower hoses, new/not rebuilt water pump,new egr valve, new egr solinoid,new egr relay,new tps,new o2 sensor,new water temp. sensor,new platinum plugs,new cap,new rotor,wires are farely new. It just had a new mobil 1 oil change and filter. It runs great at idle and sometimes I can put 30 miles on it before it overheats and then the next day it might just be10 miles and it overheats. There is no water in the oil there are no water leaks. I have done a pressure test on the system and it did drop to 14 psi but it stayed at 14psi. I looked at the plugs before they were changed and they all looked kinda brown except the #6 plug and it was a lighter color. None of the plugs were wet from water. There is no kind of smoke coming from the exhuast. There were some bubbles in the radiator but I really couldn't tell if they were from exhaust or just from the water flowing. I'm sending it to a shop next week to see if the egr is working correctly. I know it could still have a blown head gasket or cracked head but I hope not. Anyone have any suggestions??? :confused:

 

:eek: Seems like you have changed everything imaginable, you have my empathy

You didn't say, I don't believe, if you are having to replace mising coolant?

Also, I don't think I read anywhere in your post if you had checked if the fans are coming on...maybe you did and I missed it.

I had a problem with overheating in my camaro and it was fan not coming on. As long as car was moving it wasn't a problem, but standing still temps would climb.

Vette needs fans to suck in the air

Just a thought, good luck and let us know what you find

Jack

 

Welcome to the forum. First thing I would check is the fan's Yes there are two of them. Make sure that the hoses have springs in them. What happens some times is when you rpm go up the water pump will suck the hose shut. How is the timing? Cat plugged? Oil in the water? Water in the oil? Thermostat installed right? Did you purge the system? Radiator pluged?

 

Oh yea I did forget to mention both fans are working great. Any Other suggestions????

 

There is no water in the oil or oil in the water. Thermostat was installed right and it was checked to make sure it opened at 195 degrees.
What exactly do you mean was the system purged ? The timing was at 6 bf.


[Modified by Davidsvette85, 1:04 AM 9/5/2003]

 

When you fill the radiator you need to "pack" it full of coolant. With the cooling system cool start the car and take the radiator cap off. Let the car come up to temp so that the thermostat opens and coolant is flowing throughout the entire cooling system. At this time have someone hold the RPM around 2000 for you. Start filling the radiator until it is at the bottom of the cap and put the cap back on. THEN let the RPM fall back to idle.

You may have to do this a few times over a few days to get all of the air out. It took me about 6 times the last time I had to fill my system.

 

What exactly do you mean was the system purged ?[/QUOTE]

When you open up the system you will have air trapped in the block. What I do is drill a couple small holes in the thermostat. That way the air will get out of the system faster..Let me know if you are interest in seeing where to drill the holes. I can get a picture very easy.

 

hmm are you sure it's overheating? maybe a bad reasing on the temp sensor?

 

I had A bad Temp sensor that read high I replaced it TA DA it was fixed :eek:

 

Yep I'm sure it's overheating it makes that awfullest noise and fills the overflow tank and goes all over the ground. :eek:

 

I forgot to mention too both hoses have stainless steel springs inside them, and actually when it's over heating there doesn't seem to be any pressure on the hoses. :confused:

 

I'm not having to replace any coolant except when it boils it all out through the overflow tank onto the ground.


[Modified by Davidsvette85, 2:59 PM 9/5/2003]

 

The radiator was cleaned inside and out at a shop.

 

Sure I would like to see it if you can post it. I had heard of burping them and a shop said thats what they did to it but I'm not too sure if they did it right.

 

It sure seems like an air lock and the block is not flowing well.
Like Scorp said you may need to purge it a few times.
:cheers:

 

:iagree:

This is what I have done to mine. All I do is top the radiator off turn the heater on start the motor and all the air gets pushed out of the sytem in no time. But I still run the car till it gets up to temp and check it after it cools down in a few hours.

 

Great that looks easy enough, I'll give that a try this weekend and I'll let you know how it goes. Thanks for the great info.

 

Easy enough to mess up on, but did you install the thermostat upside down?

 

Good point Scorp.

The end showing in the picture points up..

 

Na I'm sure it is in there right , lol, it has this side up stamped on it .lol :hurray: