MM engine

1959 - 1962, Mighty Mite, M422, Wanted, USED PARTS FOR SALE, and Knowledge Base
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takpak
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MM engine

Post by takpak » Wed Apr 24, 2019 7:48 pm

Well, as the work on my MM progresses I am now about to tackle the engine. I just got the heads back from the shop and they turned out really good. Original valves were good, the guides were good, one head did need some repair on the rocker arm mount, but there were no other cracks or defects in the heads. So now, on to the engine. Question of the day; the pistons (rings) are stuck/seized from sitting for 50 years. I'm assuming they are ""fused" to the cylinder wall. The chrome is pretty much gone. So, the plan is to get the pistons out and send the cylinders out for refurbishment. I plan to do the nikasil treatment on them. I'm told I can't use the original ring set for the old chrome walls, so what do I use? Where can I get the right rings for the nikasil coating?? Anything else I should be concerned about? At least from the top, the pistons look to be in decent shape.
Terry K.
Vietnam Veteran
U.S. Navy
Own a 1962 M-422A1, a 1953 M-43, and a 1942 Navy EP GPW Script

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rob w
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Re: MM engine

Post by rob w » Sat Apr 27, 2019 7:14 am

Terry,

Can't use cast iron/ OEM material for rings? Nikasil and Chrome would use the same. They are both very hard coatings and need a ring that wears in...

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