Bear600rr

Working on a recently acquired 92 SL650 and having some spark issues. Currently running on 2 cylinders.

Problem is when I check the plugs for spark (hold against block) I don't see any spark. I have been checking plugs this way for years and am a bit confused by what is/is not happening. When I have the plugs in the unit it runs albeit on the 2 cylinders.... I can check them by removing the plug wire while tied to the dock but would prefer a static check method...

Is there something weird and wonderful about checking these plugs?
I was discussing this issue with a friend and told him I was going to check the coil spark by holding the spark plug lead near the block. He told me that he would not do this as it can burn out the CDI - anyone have any comments on this.

Note my experience is with motorcycles and not watercraft so I am open to any suggestions and constructive criticism.

tv4fish

Hey Bear The engine is NOT that much different from a m/c engine - just in a different "chasis" . Now, I also would not try to check spark w/o a plug in the cap. The CDI's DO put out a "hotter" spark than a conventional ignition and the spark will try to "jump to ground" through the path of least resistance, which c/b through a crack in your spark plug wires, etc. Have you tried new plugs? Put a new plug in the cap, lean it on the head and check for spark - you SHOULD get a nice, fat blue spark (not a weak yellow one). If you don't, then you have other iggy issues to check out.

Bear600rr

Thanks but been there done that. Holding the plug against the block shows no visible spark, but when the plugs are in the machine 2 cylinders fire so I obviously have spark on at least 2 - just can't see it. I am assuming the spark I have is very weak. I am buying an inline spark tester today and will continue troubleshooting.

P.S. I am also going to remove the electronics box - clean all connections, est the coils for continuity as well as plug wires etc. I will recheck the spark then install a new battery and continue from there.

I have located a pdf of the shop manual and am learning a lot there. Very little feedback on this forum when posting inquiries - a little disappointed so far....

Bear600rr

Wow almost no feedback on a spark question - I guess everyone is out riding their PWC

Regardless, bought an in-line spark tester today so I no longer require assistance. Not that I was geting any except from one member........

Beginning to wonder if I am wasting time here!