06 Supra Launch 22SSV bogging down

[motiv]

First - thank you to anyone who spends time reading this and providing educated suggestions!


Our 06 Supra Launch 22SSV runs very smooth/properly for 1-2 hours into our wake boarding trips, and then it eventually will not go past 2200-2500 or so rpms on acceleration. Sometimes we can turn the motor off for a moment, turn it back on, and it's good to go again. The only consistent thing is that it 100% of the time happens 1 to 2 or so hours into our trips.

We recently changed spark plugs as that was an "easy job" for us boat n00bs, but what else could we look at? The spark plugs we removed were rusty, and way out of gap spec - they were all over the place nothing matched. This wasn't the most well cared for boat from what we can tell.

We have a guy out here who works on Indmars and said the next step may be to clean/take a look at the fuel injectors after changing the spark plugs.

The engine is an Indmar Assault 325


Thank you!

[CornRickey]

I would look at fuel pressure next but I'm not an Indmar tech but Ive been around one and I questioned his problem solving also

[motiv]

Thanks for the reply. Anyone else?

[villain]

As a PCM and mercruiser tech they have pretty much covered all I would check. Short of shipping the ecu off to get checked/replaced

[motiv]

As a PCM and mercruiser tech they have pretty much covered all I would check. Short of shipping the ecu off to get checked/replaced


I'm having the techs come with me on a lake test this week. I guess that is the best way to actually figure out what the hell is going on rather than jabbing at random things in hopes of fixing the issue.

[MJR63]

How is you motor temperature? I have a laser temperature gun that I use to verify the gauge. I also suggest you add 2 cans of sea foam w/ your next fill up. My motor was bogging down at the beginning of the season and within 15 of running sea foam it was cleared. Great stuff. You can get it at NAPA or any auto parts store.

[jarodag99]

Just curious if you found the cause. I have an 04SSV and mine did something very similar. It typically didn't make it more than about an hour. I talked to a tech rep at Skier's Choice and he said for several year models they had issues with vapor lock. That's not the case with mine since it always starts up (just limits rpm to around 2k). I put a fuel pressure gauge on mine and it dropped in half when the power dropped. I'm in the process of replacing the fuel pump based on SC tech rep advice...speaking of, anyone know if there is an automotive comp replacement that doesn't cost 300 bones like the one from Supra?

[jzelt]

jarodag99, have you changed your fuel filter first? I have had to replace our fuel pump, but it was with another one from Supra.

[jarodag99]

Funny you mentioned a fuel filter. I bought mine new in Jan '05 and I've run the line from the tank up to the throttle body and there is no filter. The SC guy didn't believe me either. I am however going to put an in-line filter in when I get a new fuel pump. I've never had any maintenance done that may have removed it either bc I do all my own.


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[03 22ssv]

I had similar situation last year. Was sucking air from fuel tank to the low pressure fuel pump. You can trouble shoot this with a 1 foot piece of clear plastic fuel line. Install the clear fuel line with a hose barb and clamps(available at Home Depot) just before the low pressure fuel pump. Start the boat. If you see bubbles in the fuel flowing through the clear line, here in lies the problem. I replaced the original cracked fuel line and in line fuel filter. Problem solved. Good luck.