TR2/3/3A tap water will no antifreeze on new engine

So I ran the motor on this project about 3 years ago after a complete rebuild. I ran it for about ½ hour and everything sounded nice. I drained the block shortly afterwards and removed the radiator and houses. I just used tap water will no antifreeze. Yesterday I went out and was going over everything to restart the motor, and thought I would check the thermostat out because I could not remember if I had used a thermostat. Anyways, to my surprise there was a large amount of very fine hairy kinda rust everywhere in the housing, thermostat, and bypass hose. I guess because I did not use any antifreeze; I just used the tap water.


I pulled off the housing and thermostat and got a new bypass hose, cleaned the housing and thermostat out good. I am trying to think off a way to flush this rust out of the head and block before I hook up the radiator and heater. I might be over thinking this again because the rust was very light weight even kind of dusty and might just drain right out or might not even be very dense inside the engine. Heck it might be localized in the thermostat housing and floated there. The block and head were very clean to begin with and perhaps this rust is just very fine particles that did not get flushed out. Any ideas would be nice.

steve

FLAPS will sell you some very mild flushing chemical, which should be plenty for what you describe. Follow the directions on the bottle, but they usually go something like add chemical, drive for awhile, then drain, flush and refill with glycol/water mixture.

Or you could just flush with plain water.

I would remove the top hose from the therm housing (take out the therm if there is one) and put a garden hose in the disconnected rad hose and run the engine it til it runs clear.Bob