Sounds to me like you have air pockets in the system. Did the thermostat you used have a small hole in it? If not, then drill a 1/8" hole in it to help burb the air out.....


1937 Chevy Pickup
In the Gallery
1952 Chevy Panel
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1950 Chevy Coupe
Pictures!

I'd rather walk and carry a Chevy hub cap than ride in a Ferd.
I can explain it to you, but I can't understand it for you smile