The water passages on my gently aged 361ci may need to be cleaned. The coolant is perpetually a muddy red oxide color no matter how many times I flush the radiator and replace the fluid. The radiator itself has been resealed and cleaned numerous times by a radiator shop, yet the discoloration remains. I've got only water in the coolant system and it seems to cool just fine. Honestly it makes tracking leaks VERY EASY in my clean motor bay! Is there a way to clean the water passages aside from a simple flush? The radiator shop suggested baking soda.
We ran a 383 in a circle track car in the early '70's and could never get the coolant to stay rust free. If we got a block from the hot tank and went to dinner it was rusty when we got back a hour and a half later. I'm road testing some RMI-25 in my LT-1 that had some gelled up Dexcool, that was plugging up a new heater core, after many complete flushes with all drains open. Since putting in this product I've had no problems. Let us know what works. Maybe just adding a cooling system conditioner of any kind might fix your problem.
The Jalopy Journal
