3 replies to this topic

[suwaneega]

I would like to do a compression test on my 2001 Seadoo CHallenger 2000 with the Mercury M2 240 EFI engine. I just had the head seals replaced and I would like a baseline to monitor going forward. I have the service manual and their directions which include:

1. Removing plugs
2. Putting in compression tester
3. Turning over 4 times
4. Comparing results between cylinders.

My question is do you need to disconnect the ignition or fuel first before turning over the engine? Can I just use the key or do I need to rig a switch to the starter itself? Nothing is mentioned about this that I have seen. Also, do all 6 plugs need to be out at once or just pull one and check that cylinder, than repeat for the other 5? Any help from someone who has done this before would be appreciated. Thanks.

[Kevin Leclair]

See if this helps, http://seadoosportbo...y-m2-240-motor/

Keep us posted on your results.

[bstuke]

I would like to do a compression test on my 2001 Seadoo CHallenger 2000 with the Mercury M2 240 EFI engine. I just had the head seals replaced and I would like a baseline to monitor going forward. I have the service manual and their directions which include:

1. Removing plugs
2. Putting in compression tester
3. Turning over 4 times
4. Comparing results between cylinders.

My question is do you need to disconnect the ignition or fuel first before turning over the engine? Can I just use the key or do I need to rig a switch to the starter itself? Nothing is mentioned about this that I have seen. Also, do all 6 plugs need to be out at once or just pull one and check that cylinder, than repeat for the other 5? Any help from someone who has done this before would be appreciated. Thanks.

You should disconnect ALL the plug wires. That will keep the engine from starting. Tie them up so they don't arc on the engine or worse you. Remove one plug at a time, check compression, document the results, put the plug back in, and move to the next one.

Keep the turning over to 4-6 strokes. If you don't get something significant, say over 100 PSI, then you have a trouble cylinder..

Good luck.

[suwaneega]

Thanks for the replies. I saw the posting you directed me to Kevin and I have the service manual, but I was looking for the information that bstuke provided. I will try it and see how it goes.

Thanks again...