| Re: Freeze Plugs- what do i need to know ? [message #351452 is a reply to message #351443] |
Mon, 20 January 2020 11:04   |
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Matt Colie
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
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hertfordnc wrote on Mon, 20 January 2020 09:22The Revcon has not been run much for years, it's still not driving (brakes)
I was running it up to temp to set up the controller for the electric fan when steam began coming out of the right rear of the engine.
I was pretty happy to diagnose a freeze plug rather than a head gasket.
So, should i replace as many as i can reach or just the bad one?
Are some more likely to fail than others?
This engine has had mostly just water in it for the last few years
Dave,
It could be just the one plug, but that is rare. You should be prepared to replace more.
Now, here comes some "good" news. I recently (in the last few years) have had mine and other engines on the shop floor. I always take lots of pictures for two reasons: With modern cameras they are cheap AND They are better than my memory.
So, I pulled up the pictures just to be sure and you are lucky. The 455 has only three core support holes in the outside of both banks and none in the rear of the block, under the timing gear cover or in the valley. You only have to worry about the six plugs that you can see from the sides.
As KenB stated, Anticorrosion protection is one of the larger purposes of modern coolant.
Get used to calling them "Core Plugs" as they never were freeze protection and will never do that. They corrode away in untreated water pretty fast.
Now, in your specific case, I would arrange to replace the failed core plug and be ready to replace others. They are not easy to remove and the hole must be clean before replacement. When you start this operation, have a cooling system pressure tester on hand. When the first is replaced, please pressure test the system to what ever the little pump will do. It has been my experience that there is seldom just one that needs replacing.
I wish you a simple success.
Matt
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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