Packard Forum Index » Post-War (1946-54)

Is there a "common" reason for the 327 straight 8 to run hot? It would appear we may even have a head gasket issue as well. This engine has less than 100 miles on it since it was rebuilt. Any info is appreciated
Cam

Were the water passages completely cleaned of all rust during the rebuild? Also was the water distribution tube cleaned, checked and replaced if needed? This is often over looked and a cause of chronic overheating.

Some obvious things to check are a plugged up radiator, dodgey waterpump, bad or partially opening thermostat or engine timing advanced to far.

If you have a bad head gasket, then frankly all bets are off and that could be the cause of the overheating.

All the things suggested here are good candidates to check out, but the radiator should be at the top of the list. As an engine ages and accumulates miles, the amount of friction it produces gradually reduces due to piston ring wear, etc. At the same time the radiator also looses efficiency but isn't noticed because it's dealing with less and less heat. When you rebuild the engine, you're back to a maximum heat load which the aged radiator can no longer handle. I'd pull the radiator and take it to a competent shop for cleaning and evaluation of its flow rate and overall condition.

A good friend had chronic overheating problems on his 51 which turned out to be the heat riser valve not opening.

The heat riser valve was indeed the cause of overheating in my '51 as well. I couldn't find a Packard spring, so I'm trying to craft a Chevrolet spring to work.

what the hell do you need a heat riser valve for in Virginia Martha. You don't live in upstate NY in the 50's in the winter. Prop it open or better yet remove it and plug the side holes.

Both Kanters and Max Merrit carry the heat riser springs. I belive I bought mine from Kanters.