2001 Sea Doo Challenger 240 EFI doesn't idle nor start well

[stuffbert@outlook.com]

Hi. Started the season, started ok, went out on water, max 2800 RPM and about 10 knots. Took it out, replaced fuel (as much as I could pump out--then added 10 gallons premium and sea foam), plugs, both fuel filters. Now hard to start (I have to turn the wheel). Checked spark with a inline light tester, light up on all 6 (idle). Once started (on land), seems to run fine at higher RPM--ran at 3000 for a minute or two (with water attached). Bring to idle, dies. I took off the lift pump output, fuel pumps out. Not sure if it is enough pressure, but it seemed to flow ok. I did not shoot out very far--couple of inches. Should I put a pressure gauge on the lift pump output to measure? Replacements hard to find. Any thoughts?

Thanks!

Phil

 

[ripcuda]

Hi. Welcome. Yes, you need to measure fuel pressure. There is a schrader valve on top the VST tank as part of the fuel pressure regulator assembly. You need to see 35psi fuel pressure at idle. Could have a weak EFI pump. When you say you had to crank steering to lock to start (that engages OTAS and "gooses" the throttle a little)... that would imply an overly-rich flooded condition that required opening the throttles a little (for more air) to get it to start. If that's the case... could be leaking injectors... causing a flooded/over-rich condition at idle or after turning engine off (and trying for a hot restart... before the flooded fuel had time to evaporate). FYI... 3 fuel pumps. #1) square lift pump (clackity-clack)... this is an electronic fuel line primer bulb to ensure fuel line is full from tank to pulse pump. #2) pulse pump... this is driven off engine pulses... it's mounted on port side of the block... it's the main fuel mover from tank, thru filter and into the VST tank. #3) VST/EFI high-pressure pump... feed high pressure (35psi) fuel to the injectors from the Vapor Separator Tank (VST). Also... not recommended to run engine above idle out-of-the-water (even on muffs)... think there's a sticker on the boat saying that too. Cheers!

 

[stuffbert@outlook.com]

Thanks! I'll check the fuel pressure via the schrader valve. If this is low, would that direct a cleaning of the VST screens and potentially replacing that pump? Would a problem with the pulse pump also lead to a low pressure at the schrader valve? Thanks again!