96 XP won't start in water

[Mraw]

I am helping my friend with his 96 XP. The PO rebuilt the carbs before he bought it but used crappy kits, also noticed that the crank case line clamp to the carbs was loose. Could this be a cause of not starting in water? Ski cranks fine but won't start, did fire for a little bit with some fogging oil or does this sound more like a rotery valve cover issue? Either way carbs will be rebuilt with mikuni. Starts and revs fine on land but I know that doesn't mean anything for water, just found it strange that it wouldn't even start beyond a few seconds in water

 

[groundfisher]

Crankcase line is the pulse for the carb fuel pump so yes that will cause it not to start because it wasn’t pumping enough fuel through the carbs.

 

[Mraw]

Just rebuilt carbs with mikuni kits. Still will not start in water, smoke comes out of the carbs. I'm thinking rotery valve clearance. Any thoughts?

 

[Mraw]

150 psi both cylinders, fuel selector bypassed
All new fuel lines. New rectifier

 

[Mraw]

Just pulled rotery cover. Thoughts?

 

[racerxxx]

Looks fine to me.

Check for spark while trying to crank in the water. Use an extra plug so you're comparing apples to apples. Needing the starter is using the same power to start as you are to check for spark. By pulling they plugs out your making it easier for the starter to work, this defeating the test. You can do this on the trailer. If your voltage dips to low you'll lose spark. You can check the voltage too, you'll lose spark around 10vdc.

 

[Mraw]

Looks fine to me.

Check for spark while trying to crank in the water. Use an extra plug so you're comparing apples to apples. Needing the starter is using the same power to start as you are to check for spark. By pulling they plugs out your making it easier for the starter to work, this defeating the test. You can do this on the trailer. If your voltage dips to low you'll lose spark. You can check the voltage too, you'll lose spark around 10vdc.

Thanks, battery voltage stays around 12 when cranking. Will check for spark in water soon. Yesterday to test we started up the ski on the trailer and then backed it in, as soon as it went in the water it died. Repeated test with someone on the ski reving it up, same thing ski began to bog and die within 10 seconds. The rotery valve was slightly bent and around the cover it feels uneven, not sure if thats normal though

 

[racerxxx]

Pull the exhaust hose from the water box to the outlet, see if it's collapsed internally. They're known to do that. You could remove it from the water box and leave the seat off and see if it dies. Kind a hack job but might eliminate the hose.

 

[Mraw]

Hi, tried that, even disconected the water box. We have spark, over 12 volts cranking in water. We also replaced rotery valve cover, and the rotery valve. Same symtoms as before as soon as we back the trailer in the water it dies. Sometimes we can keep it running for a little bit but dosnt last long

 

[Mraw]

Pull the exhaust hose from the water box to the outlet, see if it's collapsed internally. They're known to do that. You could remove it from the water box and leave the seat off and see if it dies. Kind a hack job but might eliminate the hose.

Also, there is some air in the return line. Is this normal? Another thing we noticed is that the spark looked weak but not sure if thats normal

 

[racerxxx]

Assuming you mean the fuel run line? If so, that will only take what's extra I believe, it's not a loop.

 

[Mraw]

Thanks, anything else we should try, running out of ideas.

 

[racerxxx]

Compression?

 

[racerxxx]

Nevermind, went back and saw 150

 

[Mraw]

Didn't notice before but the PTO plug is completely dry. MAG a little wet. Going to pull carbs and inspect.

 

[Mraw]

Ok, fixed up the carbs. Ski will now start in water cold, however if you let it sit for more than 5 minutes it won't start unless you lift the intake grate out of the water. Going to double check rotery valve clearance today.

 

[Lee.Harrison]

Did you get new needles ane seats and have you checked timing for the rotary valve plate?

 

[Mraw]

Just to update. Got the ski running, engine blew shortly after. New engine, rotery valve cover, and plate on the way, there was excessive cleanece with the cover

 

[racerxxx]

Can you post pics of your old cover? I'm just curious. I've been messing with ski doo snowmobiles and seadoos for 30+ years and have never once seen a worn rotary valve cover. Some of these sleds have had over 4k miles, much more run time than a ski gets. Just want to see what yours looks like.

 

[Mraw]

Can you post pics of your old cover? I'm just curious. I've been messing with ski doo snowmobiles and seadoos for 30+ years and have never once seen a worn rotary valve cover. Some of these sleds have had over 4k miles, much more run time than a ski gets. Just want to see what yours looks like.

Sure, the origenal cover was sent to SBT for an exchange but I can take pics of the used one we put on, with that cover it would only start out of water but once started ran great. I can take a pic tomorrow afternoon