I figured I try here since I was limited response in general First off I hope someone can help me here. I have a 91 sj 650 stock motor and carb, 6m6 my problem is the ski runs and idles perfect out of water it does seem to hit the limiter very quick, in the water it will idle and except throttle sitting there at the dock but when I take off it shuts down after about 100ft, here;s what i've checked and changed, cleaned carb very thoroughly every jet and orifice even the little filter 3 times, changed coil cdi and reg/rec and new caps with known good one's checked reeds which is fairly hard with the setup yamaha use's changed fuel lines and one way valve previous owner removed fuel selector i'm at my wits end compression is 150psi ea cylinder also what does the charging system really charge at thats exceptable could my stator be bad any help would be very appreciated I tried to cover all my bases before crying for help thanks Hawaiian dave the noob to ski's
91 sj 650 problems
- Thread starter hmsikhayn
- Start date
ketsair
ISJWTA Member #1
- Location
- thomas hill reservior missouri
unplug the stop side of the start stop switch? if not... do that & don't ask any questions till you try it...
okay i'll try it it's the two wire plug by the elec box?
dajnglst
Glass Happens
- Location
- Charleston SC
Start by looking for exhaust gases/smoke in engine compartment with hood off boat running on trailer.
Check vacuum line to intake. Line tight and secured? then check nipple pressed into upper engine case, they can come loose.
If tank is in fact ventilated properly, you may inspect fuel pick up lines inside tank as they can deteriorate sucking air at top under wide open throttle getting air in fuel line. Or you may have go go gadget clear fuel lines fastened with zip ties causing the same scenario.(Don't like peak rpm vibrations/ sucking air)
If all looks OK from there then re inspect carb for proper sealing and adjust of mixture screws. Grease fuel pump vacuum diaphragm and ensure that the needle valve retention screw has not backed out and the o-ring is in good condition. Inspect main and pilot jet to see if they have come loose. The float needle retention pins get worn out from mutiple carb rebuilds also, get a new one !!!!!
BUT ALWAYS START BY CHECKING THE BLACK AND WHITE WIRES FROM THE HANDLE BAR SWITCH, UNPLUG THEM TO TEST. NEVER DO SO WITHOUT TURNING ENGINE IDLE SPEED SCREW DOWN TO CHOKE OFF ENGINE IN ORDER TO KILL IT.
You could also check battery ground cable for solid contact at battery and starter. They break down and when bouncing around could cause ignition to lose signal.
If none of that works, pull engine for leak down test, suck air without enough fuel and whhhhhhhhhhhhhhhhhaaaaaaaaaaaaaaaaaaaaa,whhhhhhhhhhhaaaaaaaaaaaa.
Check vacuum line to intake. Line tight and secured? then check nipple pressed into upper engine case, they can come loose.
If tank is in fact ventilated properly, you may inspect fuel pick up lines inside tank as they can deteriorate sucking air at top under wide open throttle getting air in fuel line. Or you may have go go gadget clear fuel lines fastened with zip ties causing the same scenario.(Don't like peak rpm vibrations/ sucking air)
If all looks OK from there then re inspect carb for proper sealing and adjust of mixture screws. Grease fuel pump vacuum diaphragm and ensure that the needle valve retention screw has not backed out and the o-ring is in good condition. Inspect main and pilot jet to see if they have come loose. The float needle retention pins get worn out from mutiple carb rebuilds also, get a new one !!!!!
BUT ALWAYS START BY CHECKING THE BLACK AND WHITE WIRES FROM THE HANDLE BAR SWITCH, UNPLUG THEM TO TEST. NEVER DO SO WITHOUT TURNING ENGINE IDLE SPEED SCREW DOWN TO CHOKE OFF ENGINE IN ORDER TO KILL IT.
You could also check battery ground cable for solid contact at battery and starter. They break down and when bouncing around could cause ignition to lose signal.
If none of that works, pull engine for leak down test, suck air without enough fuel and whhhhhhhhhhhhhhhhhaaaaaaaaaaaaaaaaaaaaa,whhhhhhhhhhhaaaaaaaaaaaa.
ok update I took the carb apart again and all the jets and vavle seat is ok, decided to check the filter again it was clean tore apart the fuel pump ,found one of the check valves and rubber trapped in the rubber diaprahm . my question is which direction do the check valves and rubbers go in I think the previous owner rebuilt and may have put them in backwards I also notice sitting in my hot garage today that my hull filled up with fuel maybe a bad check valve on the tank to thanks for your help David
ketsair
ISJWTA Member #1
- Location
- thomas hill reservior missouri
can you take a pic of your fuel line routing & post it?
it's a runner baby
Thank you to everyone that gave input on my problem. After going through everything I learned, don't over look your fuel pump, it was one little plastic diaphram that was bad that little clear piece of plastic damn. Learned alot about my sj being i'm new to the ski world. so now I can add my prop intake grate and a pipe sponsons and new paint job and turf, finish off my footholds and maybe a pole either rn or ac can you use an rn ac pole shortened, thanks again i need some sleep gotta go ride it again tomorrow wwwwwwoooooooooooooohhhhhhhhhooooooooo! hopefully I can get to the level I took my street bike stunt riding to!!!!!!!!!!!!!!!!!!!! P.S anyone have any of those parts i'm wanting to add now:thewave:
Thank you to everyone that gave input on my problem. After going through everything I learned, don't over look your fuel pump, it was one little plastic diaphram that was bad that little clear piece of plastic damn. Learned alot about my sj being i'm new to the ski world. so now I can add my prop intake grate and a pipe sponsons and new paint job and turf, finish off my footholds and maybe a pole either rn or ac can you use an rn ac pole shortened, thanks again i need some sleep gotta go ride it again tomorrow wwwwwwoooooooooooooohhhhhhhhhooooooooo! hopefully I can get to the level I took my street bike stunt riding to!!!!!!!!!!!!!!!!!!!! P.S anyone have any of those parts i'm wanting to add now:thewave: