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No fuel to cylinders Mercury 240 EFI

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tlwood

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I have a "new to me" Merc 240 EFI in a 2001 Seadoo Challenger 2000. My second Seadoo with this engine (first was a 2001 Speedster). I was running it in open water for the first time a couple of weeks ago and it died in middle of bay. It had been running fine for an hour or so but just died out when were coming out of a turn and would not restart. I had been doing some tight turns, throttling up and down, etc. - basically trying to see if there were any bugs (and obviously there were). After being towed by a friend back to pier (it is good to have friends) - I have been running through the test procedures in the manual to try to narrow down the problem.

Bottom line so far, I seem to have spark on all cylinders (although haven't checked timing). However, the plugs are all completely (and I mean bone) dry, indicating no fuel at all into cylinders. I have run through the fuel system checks, voltage on the electric pump, fuel flow at various points, etc. It seems that I have fuel all the way through the rail, and on the back end where the regulator is, although I am having trouble getting the regulator out to do the actual check as shown in the manual (need more daylight hours than I have right now to get it apart, funny the manual doesn't mention what a pain it is to get it out of the top of the vapor seperator housing), I do have fuel on the feed hose coming out of the rail into the regulator. I haven't done the pressure test yet - just picked up a gauge today to do that, but when I looked at it the other evening the volume of fuel coming out of the high pressure side of the electric pump would indicate to me that I "probably" don't have a pressure problem (maybe?). So - only things I can think of is that either regulator is bad, or the injectors aren't firing - which could be caused by what (ECM fail, ground problem, what?????) I do have a brand new battery in the boat as well.

Any thoughts on what I should be focusing on for my next set of evening tests? I do have the manual so referring to diagrams, page numbers, test procedures listed in there, etc. is fine. Greatly appreciate the help - am looking forward to getting this boat back in the water.
 
having the same problem

hi!! I'm in Canada right now and I'm having the same trouble. The only difference is that I tear the engine apart and it's start doing this after. Mine was working well before it jammed. If you find any reason why its doing that tell me please. I'll do the same if i find it before on my side of the world:rolleyes:. Good luck!!!

Yannick
 
Thanks Yannick - I am still troubleshooting and haven't come up with anything definitive yet. Will let you know if I figure it out. Tom
 
What does the fuel pressure measure? I think it's suppose to be around 34 PSI.

Something you might want to look into is how the lanyard kill switch works. How does it kill the engine?
 
Well after several aborted attempts to troubleshoot I thought it was the high pressure pump. I had a spare VST with pump, I replaced that whole component and checked the fuel pressure on the port - it was 36 psi, right where the manual says it should be. So - issue is not there. Plugs are still bone dry - so my conclusion is that the injectors are not firing and putting the fuel into the cylinders. I am now going to pull the ECM and manifold cover off so that I can get at the injectors. Then try to see if the circuit is telling the injectors to fire or not. If so, then the issue is in the injectors themselves I guess. The ground wire that provides the baseline for the injectors seems to be fine, it reads 0 ohms back to the negative post of the battery... so that isn't it.
 
no luck yet

Well after several aborted attempts to troubleshoot I thought it was the high pressure pump. I had a spare VST with pump, I replaced that whole component and checked the fuel pressure on the port - it was 36 psi, right where the manual says it should be. So - issue is not there. Plugs are still bone dry - so my conclusion is that the injectors are not firing and putting the fuel into the cylinders. I am now going to pull the ECM and manifold cover off so that I can get at the injectors. Then try to see if the circuit is telling the injectors to fire or not. If so, then the issue is in the injectors themselves I guess. The ground wire that provides the baseline for the injectors seems to be fine, it reads 0 ohms back to the negative post of the battery... so that isn't it.
 
If you figure out what parts you need I have a blown 240 efi engine in a 2000 challenger Less one bad piston and and a cracked block.
 
Great Thanks. I am borrowing a DDT tomorrow, see if I can get some more information to work with. Hopefully will know more tomorrow evening. If I can figure it out, I'll drop you a note. Tom
 
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