if tap water is bad for CTD motors is it bad to use tap water to flush out the system? i understand the coolant to distilled water ratio. but to get the old coolant out people use regular tap water to flush the system. there is residual tap water in the system.

is there an optional method or is tap water not so detrimental?

thanks

 

I think for flushing it out, your alright. My buddy has a 92 Suburban with the original 454. Has over 340K miles on it. He's used tap water everytime he's flushed it AND filled it. No problems yet. Still got the original water pump on it as well. Never once over heated on him.

 

https://www.dieseltruckresource.com/...shing+radiator Check this thread out about flushing.. Flushing with water is ok, just mix with distilled when going back. Goodluck,,Rick