Compression for a Super C

Mark-Mo · Nov 1, 2009

My old Super C runs good, but after a while it will start to smoke some and uses some oil, As you can tell I am no mechanic. What should the compression be? It show between 70 and 85 pounds on the cylinders.

Jeff Z. · Nov 1, 2009

I don't know what it should be as a new engine but I would guess well over 100. The numbers you posted sounds like the engine will be needing some work.

Andrew Z · Nov 1, 2009

125psi is for stock

Andrew

AndrewFromNS · Nov 2, 2009

My Super-C was rebuilt recently (~75 engine hours ago), and tested within a couple PSI either direction of 125psi. I recently tested my new H, and was told that I'd be lucky to see 100, and that anything under about 80, or a variation of more than about 10%, and I'd want to do a rebuild.

NawlensGator · Nov 2, 2009

I have 123C engines in 2 140"s and both show 150 PSI +- 2 psi (cold). Make sure the fitting seats in the plug hole or it can throw it off > 25 psi.

Compression for a Super C

Mark-Mo

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Jeff Z.

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Andrew Z

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AndrewFromNS

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NawlensGator

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