highleymd

My 61 Starfire leaks coolant which accumulates on the valley cover beneath the intake manifold. It's not leaking around the thermostat housing or the hose connections or the heater control valve. I assume there's leakage at the gaskets where the intake bolts to the cylinder heads. There are no signs of head gasket problems, compression is normal, no combustion gases in the coolant, it runs fine. Are there any other possibilities before I pull the intake manifold? Any thoughts on the best source for replacement gaskets?

Charlie Jones

A small mirror and a flashlight may help you spot exactly where the leak is .
The most likely suspect will be the "water " ports at the front of the intake .
Before replacing the gasket make sure that the surfaces are clean and flat . Check them with a straightedge and a .002 feeler guage , if possible .
Fel-Pro gaskets are a good choice . Usually available on order from O'Reilly's etc. or E-Bay.

highleymd

Thanks for your help.

Charlie Jones

Since you have a '61 Starfire , why don't you come and join the "Darksiders" at this thread;
https://classicoldsmobile.com/forums...ers-unite.html

chequenman

Like Charlie says get a small mirror and look under your connections onto the heater control Valve at the rear passenger side. They are notorious for leaks where they bolt to the Block and where the Valve tightens into the mounting bracket. When it leaks it will be difficult to detect but the coolant will lay under the intake manifold on the Valley Pan. Sometimes the Vacuum diaphragm will weep as well.

61Bat

You can rent a coolant system pressure tester at most any Napa or AutoZone Etc. Pressurize the coolant system with the car off and look for your leaks with it not running. You can also put dye in the system so you can see the leak easier or use a blacklight.