Thread: Coolant Leak

Hey guys,

Sorry I haven't been on in a while but I've been busy you know how that goes. Anyway, I changed the thermostat in my car and filled up the cooling system with a 50/50 mix of antifreeze and water and I noticed when I was done the system never pressurized the engine got to around 190/195 and stayed there, heaters blowing hot but when I was putting up I noticed antifreeze leaking out of the radiator drain and the petcock is completely shut. So I am wondering to I need to replace the radiator again (this would make my 3rd radiator) or can I just replace the petcock? Please help.

Thank You

im still wondering why any one uses the rad drain at all. all they do is break.

being i have no idea what this petcock even looks at im not sure whats wrong with it. all i know is i stopped using rad drains in the 80's cause they break all the time.

next time you need to flush your coolant try my way. you only take the upper hose off the rad.




how to flush coolant:

remove the t stat, put the t stat housing back on, take the upper hose off the radiator, then push it down to the ground to a bucket or let it fly.

get your garden hose out, put it in the rad turn it on, then fire up the car, let it run till clear water pumps out the top hose.

then turn the hose off, run the car till no more water comes out the upper hose. then turn it off.

put your t stat back in, with new gasket, the upper hose back on.



now take 1 gallon of full strength green antifreeze, not the 50/50 crap. ( parts store cheap green is fine to use) dump the whole gallon in the radiator, fire up the car, fill the rad with hose water till its full. top as needed till its ready to be bled of air. it will burp and take coolant as the water in the block warms up the t stat opens up for a few seconds till cold coolant hits it and it shuts again.

now to bleed the air out, let it idle rad cap off till the fans turn on, (when the fans are on the temp is over 195 deg, the t stat is wide open) then open the bleeder screw on top the t stat housing a few turns till a steady stream of coolant comes out the hole, shut the screw, top off the rad. cap it.

Ok here is an update, I seem to have the coolant leak fixed I bought some of that BARS brand radiator stop leak and its seems to be working, anyway I have a new problem regarding the cooling system: It won't pressurize the way it should. With the thermostat fully open the radiator caps is hot, the upper hose is hot, but there is no pressure on it. That being said I am wondering if the water pump is bad, I believe it is the original one that came with the engine with 202,000 plus miles on it. What are your thoughts?

Originally Posted by Scottydoggs

im still wondering why any one uses the rad drain at all. all they do is break.

being i have no idea what this petcock even looks at im not sure whats wrong with it. all i know is i stopped using rad drains in the 80's cause they break all the time.

next time you need to flush your coolant try my way. you only take the upper hose off the rad.

Scotty I have NEVER broken a rad drain plug and don't know anyone else who has either.

Originally Posted by tgarison

Ok here is an update, I seem to have the coolant leak fixed I bought some of that BARS brand radiator stop leak and its seems to be working, anyway I have a new problem regarding the cooling system: It won't pressurize the way it should. With the thermostat fully open the radiator caps is hot, the upper hose is hot, but there is no pressure on it. That being said I am wondering if the water pump is bad, I believe it is the original one that came with the engine with 202,000 plus miles on it. What are your thoughts?

Using Bars stop leak was a BAD idea. As for not pressuring you have an air pocket. Bleed the system.