compression on a 9.9 pull start

[billhig]

I did a compression test on my 1999 9.9 2 stroke and it was 90-92 psi on both cylinders. That sounds low to me but I've never tested a pull start motor before. Is this low or okay?

 

[airshot]

Speed of your pull, accuracy of your tester, was the block cold or warm, lots of things can affect the reading...

 

[keithb7]

I have a pull start Merc 1979 9.8 2 stroke that only makes 76 psi. Sure it is low. Yet it runs well and idles very well for hours on-end while fishing. (trolling). The one thing it seems to struggle with is a cold start. It won’t suck hard enough to pull in enough fuel from the carb. A small squirt of raw gas into the carb, she fires up immediately and runs quite well.

I wouldn’t worry about 90-95 psi. That would be like a new motor to me. Lol. Let ‘er rip!

 

[jimmbo]

Both cylinders are close to each other, and these 2 strokes aren't high compression Engines. So if it runs fine, I wouldn't lose any Sleep over it