Challenger 1800-240hp Won't Start/Run

[poachadoo]

I have a 2001 Challenger 1800 with 240hp M2 jet drive & last year it started cutting out periodically - mostly at 3/4-WOT cruising speeds. Boat would initially fire right afterwards but the problem got more frequent & at the end of the season, the boat would fire for only 2-3 seconds & stall.

I replaced the large fuel filter & probe which did not fix the issue. I brought the boat into a local ski-doo/sea-doo pwc dealer & they indicated low fuel pressure but could not pin-point to which of the 3 pumps were causing the issue.

In my mind it sounds to me like the high pressure pump located in the fuel vaporizer is what is causing the issue.

I really love this boat & it is the 2nd doo sportboat I have owned. Any feedback or assistance is greatly appreciated!!!

 

[WAJetboating]

Recommendations...

There are three fuel pumps and four fuel filters on your engine. It's possible the high pressure fuel pump (inside the vapor separator tank) is failing, but there are a lot of more likely causes to be ruled out first.

If you want someone else to diagnose the problem, take it to an actual Mercury shop. They will instantly recognize your engine since it's the same V6 outboard powerplant that Mercury has been shipping for years.

If you'd like to diagnose it yourself, here's the service manual for your engine:

http://articles.richardhartman.net/jetboat/240EFI_MY2000/

Go to chapter 3D, "Fuel Injection":

http://articles.richardhartman.net/jetboat/240EFI_MY2000/3d.pdf

...and go to page 3D-28. There are a series of fuel flow tests that will tell you if you have sufficient fuel flow at various points in the low pressure system. They are presented in reverse order of distance from the fuel tank.

If those all check out, that chapter also has tests for the high pressure system.

You mentioned replacing the "large fuel filter and probe", by which I believe you mean the fuel/water separating filter on the starboard side of the engine. You should also replace the inline filter on the port side. The hose coming from the fuel tank connects directly to it. It screws into the first (electric) fuel pump and can be purchased from any Mercury dealer, part number 35-889615, ~$8.50.

Beyond that, there are two more internal fuel filters. Those two actually filter the fuel+oil mix. They are inside the VST, and the high pressure tests will reveal if they need cleaning.

Hope this helps, and report back!