Hello everyone, back again....well the boat won't go over 3500 rpms, we already replaced spark plugs(twice)...the trigger...the ecu...the boat also would start in forward or reverse, it won't matter, what got me thinking is on limp mode...also my kill switch don't work...I been all over the Manual and l can find an answer....hopefully a little help from you guys more experienced would be the key.
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Seadoo Challenger 1800 wont go over 3500 rpms
- Thread starter Malkel123
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What year?
Have you checked--
Voltage with engine at 3500rpm? In the water, not on trailer. Should be about 13.3v.
Two people makes it safer.
What happens if you jam throttle level to full? Does it die or rev higher?
Check the trigger (again). 6 wires coming out from under the flywheel. Ohms reading of the 3 pairs should be close to the same. Best if you can check it while it is warm from engine heat.
Disconnect black w/ yellow stripe wire (top to engine, aft of flywheel). Test engine again. Any change? From that connector, to E-stop kill switch, check that wire at the switch. (Checking for breaks). Check the kill switch itself for function.
Back on the trailer. Compression check. All spark plugs out. Full throttle. Hoping for 135psi.
Safety shift interlock- Need to remove shifter mechanism at helm. There are 2 small (delicate) wires on the shifter. You will need to trace these and make sure they are connected and secure. There is a magnet on one lever and a magnetic switch on the other. When these are together, it should be OK to start.
Do you still have the throttle guardian in place? Small black box next to fuse block in helm box, about 1" x 3" x 4". They are known to cause lots of problems. Strangely, not every boat got them. If you have it, find the black w/ yellow wire (yes, the same one). About 4" from the TG, cut that wire. Protect the ends and test engine again.
Hey Tim...check trigger (is brand new 2nd one)...compression is 122 psi all around the 6 cylinder...I have to check the 2 wires under the throttle...once before on the trailer it was Rev all the way to 6800 rpms...now it don't matter trailer or water...it would only go to 3500 rpms...even if you disconnect the throttle cable from engine and do it manually it won't do it...just 3500 rpms...it's kind like loosing half of the engine right?
ripcuda
Active Member
I had a similar problem. Same engine. Mine wouldn't rev over ~4k rpm. Turned out my #1 (top/right-side) and #4 (middle/left-side) cylinders were losing spark above ~2400 rpms. The engine just couldn't power beyond 4k running on only 4 cylinders. A good tip given to me was to use an inductive timing light (clamps around spark plug wire) to test if you are getting spark on cylinders. So back in the water... have someone throttle up to recreate the rev problem and confirm you are getting spark on all 6 cylinders.
In my case, I had a bad trigger. It ohm-tested fine... so took me a while to pin-point it. I used a CDM tester harness (as described in service manual) to test running voltages put out by stator and trigger. I was able to see the trigger voltages at the CDM... and the one trigger for cylinder #1 & #4 dropped voltage above ~2400 rpms... thus the reason those 2 cylinders stopped sparking.
Good luck.
In my case, I had a bad trigger. It ohm-tested fine... so took me a while to pin-point it. I used a CDM tester harness (as described in service manual) to test running voltages put out by stator and trigger. I was able to see the trigger voltages at the CDM... and the one trigger for cylinder #1 & #4 dropped voltage above ~2400 rpms... thus the reason those 2 cylinders stopped sparking.
Good luck.
I agree with Ripcuda. You probably have at least 2 spark plugs not sparking. The big question is WHY? It could be one or 2 bad coils. Or a bad trigger. But are they bad or not getting signal to fire? If you can find out which coils are not firing, you can swap the bad coils for known good coils. Does the misfire stay where it was or move to the new coil location? If it stays where it was, the coils are probably good. They are not getting a signal to fire. If the misfire moves the the new location, you probably have bad coils. One bad coil can cause another coil to not fire.
OR-
You could have injectors not firing. Do all the spark plugs look the same? Do some look wet and some dry? If they are all dry and all spark plugs are firing you may have a bad injector or 2. Stop running until you know for sure. No fuel from an injector also means no oil for that cylinder.
Stop revving your engine on the trailer. It proves nothing. You could rev to 6800rpm on just one cylinder. No-load revving like that can explode your engine. No more than 2500rpm out of the water.
Look at the throttle body to see if the throttle plates are actually opening 100% with the throttle lever.
richkirwan
New Member
Do you know where the Stator is located? I am having the same issue and would like to do the myself if possible? Seadoo Challenger Merc 240
richkirwan
New Member
Thank you
brevard2002
Member
I seem to remember there was an electrical box called rev limiter, I no longer have the boat, 2002 efi 240, or manual but I thought it had one
Hello everyone, long time, hopping everyone is safe and in good health...well after some year, got the boat again, same problem with not going over 3500 rpms, got a new tps it did help, now is at 4000 rpms, lol, I'm waiting for the coils and the cdi, but another question I have , can anyone help me with the little vacuum lines around the engine?...for the life of me I can't see anything on the manual for it....thank you in advance.
ripcuda
Active Member
As mentioned previous in this tread... my can't rev above 4k saga thread here:
Challenger 2000 w/ 240 efi (gen1) - can't rev beyond 4k
The little vacuum lines are part of the "Bleed System" that sucks any pooled fuel/oil back into engine to be burned and one separte line gives lube to top of crank. Here's a diagram from service manual:
Cheers!
Challenger 2000 w/ 240 efi (gen1) - can't rev beyond 4k
The little vacuum lines are part of the "Bleed System" that sucks any pooled fuel/oil back into engine to be burned and one separte line gives lube to top of crank. Here's a diagram from service manual:
Cheers!
Checking in, I did a check on my trigger CDI brand, and it was checking at 967, 968, 968 ohms....readings shows okay, but funny when I started moving the cables with my hand(volt ohm meter still on the pins) ...ohms would jump to 1200...l order a new trigger just in case.
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