Re: Flathead Overheating

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Roy & Brenda Lange

Clint and Namcy:

My basis for this is form my 53’Merc:….As to the water all over the engine bay…if you have a overflow tube going down the side of the radiator, it probably stops shy of the lower sheet metal. Take a piece of tubing and put it on the bottom over flow tube down through the metal pan…that way the water will flow on to the ground. The fan is picking up the water now and spraying it all over the engine bay….this will keep the engine bay clean but not fix the proublem.

If as Virgil and Sue said the head gaskets are swapped then the only option is to pull the heads and correct it…..not a big project if you have a torque wrench… can do it in a day.

I would guess that you have an air pocket in the block, so it is not cooling. When you fill up the radiator leave it low to allow for expansion of the fluid and the air to come to the top and then let it idle in the drive way and watch for the air bubbles. When they stop, torn off the motor and  fill up the radiator – leave about 1 1/2 ”  to the top to allwo for expansion.  One last thing…have you checked the radiator cap…the 53’s needed a 4 lb cap….it should say on the top of the cap. I am in the membership book if you want to call….Roy and Brenda Lange , Confier Colorado. God luck.