maestro1024

Coolant leak near thermostat housing

I have a 66 coupe 6 cylinder. Recently had the head off to be reworked and finished putting everything else back on.

Problem is I have a coolant leak below the thermostat housing.

I pulled the housing back off and put another gasket in there with some gasket grease to form a better gasket. But have the same leak.

I can't quite tell exactly where the leak is coming from. Doesn't start till the motor gets warm.

I did not replace any houses (I may try a new radiator hose next).

Any ideas on figuring out exactly where the leak is coming from (it is just a stream now from below the housing but with the motor running or even with it off I can't really see where it is coming from). Or better yet a good way to stop it (or what else to try)?

rtintwo

Rent a coolant system pressure tester from a parts store and get a good flexible mirror. When you get the cooling system pressurized you will be able to get in closer to where the leak is with out the dangers of the running motor and you should be able to see exactly where the leak is coming from with a morror and flashlight.

If you are still having a hard time finding the exact spot it is leaking from even with a pressure tester and mirror. Blow the area dry with compressed air and spray a thin coat of baby powder on the area. Slowly pressurize the system and look for the spots where the powder changes color and that will be your exact spot where the leak starts.

kalli

or just dry it all up with kitchen paper. once bone dry, lay it out with kitchen towel switch on the engine and observe which part is getting wet first (from the hose, from the thermostat gasket etc)

Canary94GT

I had the same thing happen - I rebuilt the head and went to reinstall the thermostat housing and found leaking from that area. I did not replace my hoses either. But I found that the leaking was from the hose that went into the thermostat housing, as I did not tighten it down enough.

If your hose is significantly tight yet you are still having leaking problems, your thermostat housing may be warped or something. Follow rtintwo or kalli's steps then.