Hi Joe,you have no pressure when cold,do you have sufficient pressure when hot?You didn't mention replacing the rad cap,if you have an aftermarket cap on it may not be the right pressure,or if the cap is old it may not hold pressure as well.Check the neck where the cap sits as well as the seal on the cap.I would think the rad would have to be pretty plugged up to give you flow worries.Good luck,Kyle.

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