Re: Minimum compression?

[Phil Budne]

80+ would be best even on the low hp ones. A 3 hp 50s twin will idle amazingly low with 80+
I will usually take one in the 70+ psi range especially if it’s very nice cosmetically. I find that flattening the head and deck and using a new head gasket will often gain me 5-10psi on the comp. reading.
Also if the rings are stuck it will comp. better when they are free. I have a 1952 Johnson 3 hp that I don’t dare try to take apart because it’s been in salt a lot, but it has 88 psi comp. and runs great so I don’t really need to take it apart.

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