97 GTX No Spark

[Jeff77z28]

Hello, I'm new to the forum here. Good Automotive mechanic but a bit new to the SeaDoo Repair stuff. I had an 89 that I rebuilt the engine on years ago and now have a 97 GTX with no spark. Compression is excellent in both cylinders. Where do I start? Coil? MPEM? Anyone have a good diagnostic tree on how to diagnose the electrical system? I have a shop manual on order. -Jeff

[96XPSS]

Welcome to GH!

First things to check on your ski are the small ground wire from the black box to battery ground. Then good battery condition. Replace spark plugs with a new set NGK BR8ES.

Let us know if one of there aren't it.

RQ

[SURFnTURF]

Check inside the black box for water damage or bad earth connections as this is easily overlooked.

[FLjoyrider]

pick up a manual and start checking the electrical components. PM me and I can send you an electronic copy for the 97 seadoo's. It has instructions and the ohm readings to check for on the stator and ignition coil (with a good multi meter). If those check out good on the meter then its the CDI. Before doing this, I would make sure the spark plug caps haven't come loose from the wires, all your connections are good and look around where the wires come from out of the cases to see if they are cracked or broken. If the stator tests out at 0 ohms on any of the coils where it should have continuity, pull it out and check for broken wires. You can always replace a wire and solder + shrink it if you find that its broken close to the coils.

[Jeff77z28]

You guys refer to a "black box". Is that the MPEM which on this boat is inside the sealed gray box up front. All wires and common ground posts look very good. No corrosion. I would like to understand what ohm readings should be on the MPEM takeouts and how to check the stator inside the front case cover. Also, how do I check the coils where the ignition leads go in? Have a good digital Fluke meter so that is not an issue. Thanks for the help so far! Jeff

[shooter98xpl]

Pull what they call the rear box (its the one up front that has the coil in it) and check that the fuses inside are not blown.
Make sure all connections are plugged in as well.
Yes its in the grey box, but before you go pulling all that out, download the manual off this website. Just type in seadoo manuals in the search. They are free.
Start with the simple easy stuff first before you dive into the hard stuff.
SHOOTER

[Jeff77z28]

Okay, I was wrong (again!). The 787 in my 97 SeaDoo GTX does have weak spark, very weak. It is not the plugs. I took them out of the picture. It will barely jump a gap using a screwdriver. I tested the primary and secondary side of the coil and the resistances check okay, but the coil can still be bad right???? Anyone have a known good coil that they want to sell?

Jeff

[96XPSS]

The coils seldom fail, it is bad grounds normally that cause the weak spark. Although it seems you are taking the easy way out, I would check all grounds like previously instructed and then zero in on the coil. A weak battery can be the cause too.

[skibums4life]

test to make sure its starting at the route of your problem, being the battery then move forward, you can trace to see where the loss of power is occuring