super jet motor is bogging?

[jonny23]

i have a 98 super jet and it idles fine and starts fine but once you start to ride it and it starts to bog and miss alot. almost like its notting getting complete spark. any answers?

 

[Superjetjim]

Sounds like you coil or HT leads are breaking down - pretty common on the SJ buddy..

 

[jonny23]

ht lead?

 

[Superjetjim]

Spark plug leads..

 

[jonny23]

can you explain a little more. thanks

 

[Superjet3]

can you explain a little more. thanks

Cut back you spark plug wires and put on some new caps.

 

[jonny23]

thats common on sj huh?

 

[showmepro1200]

What should be common is to ask you what mods or changes you possibly made, or what happened just as the symptoms started....

 

[jonny23]

i recently bought it and the guy couldnt figure out what it was so he gave me a deal on it. has b pipe, filters, msd

 

[Superjetjim]

Best way to fix (if it is the leads/coil) is to buy a new coil with stock Yam leads attached as a sealed new unit - a little costly but fixes it properly. You can 'Cut back you spark plug wires and put on some new caps' to test if the leads are the problem but I wouldn't run it like that for a long period of time - it will likely fail again shortly after.

Cheers

Jim

 

[grahammy]

It could be anything, fuel starvation, exhaust leak, sparkplug, ignition - you say MSD, is that total loss?
Does it run fine with the hood off and then crap with hood on - exhaust gas leak.

 

[Mike W]

I'm dealing with coil issues right now but different symptoms. Sounds like you need a new coil. It runs fine out of the water but in the water there is a load on the engine. In turn the spark plugs need more energy to fire so if there is a break in the coil wires the energy can not make the "jump" between the break. It would need even more energy to fire if you were running higher compression. Make since?

 

[jMike]

If the ski will run fine after you get it through the bogs and misses maybe its a fuel starvation issue..

It sounds like what i just went through with a lean on the low end of mine.. did your elevation change from the original owners? did they rejet after the FP was installed? Try turning the low screws out at 1/4 intervals until it seems to make another change for the worse (too rich) ideally, if jetted to the prop range, the screws should be in the 3/4 to 1 1/2 turn out range.. if that doesnt work you might have to change your jets.. If that doesn't help look towards the coil next..

 

[jonny23]

thanks guys. like i said it runs fine on the trailer and revs up great and idles but once you put a load on it misses really bad. im believing its the coil. will try that and inform you all on what happens. thanks again

 

[jonny23]

could it be the stator or cdi?

 

[RabbitX29]

...

my buddy just went weeks trying to figure out the same problem! it ended up being his fuel pickup... yours could be something different, but its just another thing to check!

 

[jonny23]

what and where would the fuel pickup be?

 

[Mike W]

what and where would the fuel pickup be?

The pickups are actually down inside the fuel tank. Its the part that has the 2 fuel lines coming out the top of the fuel tank.