RESTO seadoo project gtx 787

[shendershot731]

At work just stewing about my problem.
-I did notice that one spark plug was alot warmer than the other.
- when at 3k rpm on the water the engine will die if the choke is pulled doesn't fix the problem so I don't think I am running to lean.
- when on the water it won't go above 3k rpm. if I hold it long enough it will start to back fire I can feel it, so it seems like I am getting to much fuel as it is making its way to the exhaust then firing. Is this correct thought on this?
- I tried to not mess with the LS adjuster it should run right at stock.
so Tried LS adjuster from a range of 1/2 to 1 to 1.5 turns out no difference except on the smooth Idle.
- I don't really want to give up on this thing, but I am afraid it is a engine leak issue somewhere.
- I started with a box of parts and put this thing together I am proud of the fact that it runs, I just want it to run right.
- when I pull the spark plugs out they are black and wet so Still tells me to much fuel.
- I did try a different set of NGK spark plugs and same result.
- out of the water it will rev up to 5k rpm but it is stuttering and backfiring.
- I am tempted to just buy a new engine for $1000 and drop it in, but it seems like it should be something simple like a fuel circuit not opening on one of the carbs. I need to check the Exhaust hose again I took off one end and not the other it could be it.
- anyone have a video on how to sync the carbs youtube is sucking for those things lately?

 

[TheGTIjetguy]

Don’t give up.. I think you have a spark problem. One cold/colder plug and choke not affecting the problem are your clues. My 720 with a brand new aftermarket coil would run decent but not go over 15 mph. Backfired and carried on but just wouldn’t rev out. Black and wet plugs no matter what.
A new oem coil from leaders rpm and it runs like a scalded dog. The aftermarket electronics are junk unfortunately

 

[TheGTIjetguy]

Lack of fuel or lean running causes bogging, kinda sounds like the groan that someone makes when they get the wind knocked out of them. An engine air leak would fall into this category. More throttle will make it worse or shut it off, so probably not what is happening.
Too much fuel can cause backfiring but it has to be really bad to not allow it to rev out in the water. Under load these two strokes will clean themselves out under throttle and eat a lot of fuel. Too much fuel usually shows up at idle in the form of loading up, etc. just my thoughts on why I think it’s electrical.