3 replies to this topic

[Odessaboy1]

Hi
Can anyine list a step by step instruction or point to existing instructions on how to perform compression test on Mercury M2 240hp?
I appreciate prompt response.

Felix

[Kevin Leclair]

I found this on another website, it gives an overview.

"I changed plugs and checked compression today. I also found the compression test instructions in the manual, paraphrasing...

1. remove plugs.
2. install compression gauge.
3. hold throttle plate at wide open. (I assume this is to allow air in faster)
4. crank through at least 4 compression strokes.
5. check and record, want no more than 15 psi variation.

I also removed the emergency lanyard and cleaned/vacuumed area during process. It was extremely easy, and I was surprised at the clear access to the plugs (only needed a small 3/8 wratchet extension for the top port side plug b/c of nearby hose).

Readings were 138, 138, 138, 135, 139, 136 psi (all readings are probably +/-2 with the gauge used) , so hopefully a sign of a healthy 240EFI with a lot more summers to come!"

[Kevin Leclair]

And then here is the process taken straight from the Mercury 240 manual.

 5-28-2010 8-14-20 AM.png   62.13KB   42 downloads

[frgman]

i need the oil mix ratio for a 2001 mercury m2 in my utopia 185