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From: sosmi@xxxxxxxxxxx
Dan, Cleaning, and flushing the cooling system seems to be a good idea, BUT there are some concerns.The freeze plug issue is one, the block plugs aren't to bad to change, but the head plugs can be a problem, the ones behind the exhaust manifold, and the ones behind the head, and the fire-wall.One other big concern, is the head-gaskets, I've seen head gasket failure after using some of those aggressive cooling system flushes. The water pump is another, and don't forget to use only distilled water for top-offs, after you get your cooling system "RIGHT". When we build an engine, we use marine head gaskets, they were designed for the WORST cooling system conditions. Ya'll have a nice day, Dave.-------------- Original message --------------
From: therichardsonfamily@xxxxxxxxxxx
Hello experts:Some super duper, heavy duty, clean the block questions:My '67, 440cid, Imperial engine has some major crud in the cooling system of the block. I had anticipated pulling the engine and rebuilding everything - now I'm finding it still runs strong and I think I will try cleaning it out while still in the car.I've read the web-site regarding freeze plugs etc. - now I have some flushing questions. The radiator is now brand new and not been used. I want to flush the block and pull freeze plugs to get the gunk out.Is there some type of solvent/cleaner I could send through the block to help loosen the gook? Any other advice on cleaning out some probably very clogged up coolant passages?I will set up bypasses for the new radiator and old heater core to prevent any dis-lodged gook from causing more problems. Is there a backflush or pressure-flush strategy for the heater core, as it would stand alone? Any other experience to share?Thanks in advance for the help.Dan Richardson300L Family Heirloom