Re: Intake Manifold ‘Hot Spots’

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In this car hobby there are times we need to decide if we want to drive the car and enjoy it or do we want it to stay in the garage as a tropy car.  That “HOT” spot on the intake manifold is the result of exaust gasses passing through the intake manifold under the base of the carb.  There is a reasion for this and nothing is wrong with your engine.  All engines are built this way.  As Jerry said, without this, the intake runners can freeze with ice.  My cousin was driving her small block Chevy one foggy Nebraska afternoon and the temp. was just right so that the intake air froze in the intake runners and blocked them completely off.  Yes, she had a stalled car.  After sitting at the side of the interstate for a while, the heat from the engine thawed the runners out so the engine could breath and she went on.  What had happened was the exaust runner in the manifold plugged up with carbon from many miles of service and there was no heat to the base of the carb.  Also, Jerry is correct in saying this will affect the automatic choke.   All the time!!!  The choke needs this hot air to function.  So, bottom line, drive it and live with the paint burning off or let the car set and trailer it every where.  The paint on our 64 390 has been burned off since I painted the engine 20 years ago and I live with it because I want to drive it!!!!  Enjoy your Mercury!!!   Joel