View Full Version : 2003 Seadoo Challenger 240 Merc drive won't rev

06-25-10, 03:12 PM
I've just inherited an early 2003 Seadoo Challenger with the Mercury 240 EFI jet drive. It drove the previous owner nuts.

The problem is that it starts and idles, but giving it any more than a bit of throttle kills the engine. The ECM has supposedly been repaired numerous times and the mechanic who does not want to work on it any longer says it still needs an ECM.

I've just had a look at the engine compartment and have noticed two wires have been cut near from one of the terminal connectors. The connector is near the ECM but does I can't tell where the other end of wires would go.

Are these machines known for ECM problems? Any ideas as to what is really wrong with this boat?

Big thanks,

06-25-10, 03:32 PM

Have you checked your fuel, filters, etc.?

You might want to move this to the boat forum, you'll probably get more help.


06-25-10, 11:28 PM
Yes, the fuel and filters have both been changed (more than once actually).

I'll take your advice and repost to the boat forum.


Dr Honda
06-26-10, 06:51 AM
I don't have a lot of experience with the Merc drives... but no... they are not known to have ECM issues. If they did, we would see it more often here.

I would figure out where those wires go.

Most of the time, we see bad fuel pumps, or plugged filters.

Just a thought from an experienced mechanic... if the ECM, or other electronic module was bad... the engine wouldn't run.

I would start with putting a fuel pressure gauge on the fitting near the regulator, and verify that you have good pressure while running. (I've seen a couple regulators go bad)

Last thing. If you join this forum (become a premium member) you can download the Merc engine manual.

06-27-10, 08:36 AM
I'd start it in neutral and shift it into reverse to back away from the trailer. When I shifted it and gave it any throttle, it cuts out. Tried that 6 or seven times before pulling it back out of the water.

There shouldn't be much old gas in the tank from winterization. I've topped off the tank twice this year with about 15 gallons each time. The last time out, when the battery crapped out, it did seem to sound "bogged down" when throttling up.

Suggestions? Fuel filter? Fuel pump? Something else?