Need a couple questions answered about my 1993 seadoo xp

[seadoo/skidoo]

If someone could help me out with a couple questions i have that would be great. i had it in the water a couple days ago and it runs great the guy i bought it off of rebuilt the motor and the compression is 150 both cylinders but once you shut it off it doesn't like to start back up easily unless you feather the throttle. the carbs do seem like they need rebuilds but i have a feeling thats not the problem. im almost certain it needs RV shaft seels so my question is could the crank case be getting flooded with oil once i shut it off therefore making it hard to start because theres to much oil in the case? it seems to foul plugs alot and for the first 5 mins of running it in the water you see lots of smoke but after that it goes away. also when there is 2 people on it, it almost never starts for some reason? so if anyone could answer why this is happening that would be great thanks :thumbsup:

 

[Bills86e]

1. You did the compression test, top end....its good.
2. Pressure test the lower cases. This will tell you if the crankshaft seals are leaking or not. (smokes)
3. Check the squish in the rotary valve cover. Excessive means machineing the cover back to spec.
This makes starting easier and saves the starter from an eary grave.
4. Are your *plugs wet? If so, its time for new needles & seats & carb cleaning. This can make hard starts
and smoke too.
5. Consult the Shop Manual for pictoral How-to of the above.

 

[Dr Honda]

That is the classic leaky needle symptom.

If the RV seals were leaking as bad as you are thinking... the engine would hydro-lock, and wouldn't crank if it sat over night. I'm not saying your RV seals are perfect... but most of the older seadoo's leak, and will smoke when they sit. (especially over the winter) BUT... the extra fuel, with a lightly leaking RV will foul the plugs too.


The hard start can be from leaking, old carb needles... or an aftermarket diaphragm. The "Windrosa" kits are the worst culprits of this problem.

 

[seadoo/skidoo]

thanks bills86e how do you pressure test the lower case to make sure the crank seals arnt gone? i dont think it needs crank seals because the guy i bought it off of had the top and bottom end done by a marine shop so the seals should be new. also what are the squish in the rotary valve cover? once again thanks so much :thumbsup:. and thanks Dr Honda yea i think that the carbs need rebuilds because it seems like it floods when you turn it off so what i do is make sure i turn the gas off right away so it starts easier. also my RV cover i guess you call it has oil leaking out of it (not oil and gas) just oil so thats why i think my RV shaft seals are leaking should i just replace that gasket so oil doesn't leak out of there and make a mess? once again thanks to the both of you :cheers:

 

[Bills86e]

Squish is the amount of clearance such as the measurement at piston TDC and the cylinder head. Your ski
would be good at .053. Your RV spec and a pictoralized instruction is in your Shop Manual for your ski's engine.

TO Perform a leak-down test: Use a piece of rubber (you can cut up an old bicycle tube) block off the intake before the carb as well as the exhaust as a blanket gasket and slowly apply pressure through the pulse fitting. It should hold 10psi and leak down no more than one psi per minute within ten minutes. The crank case can fill up with oil thru the center seals, as when the inside of the engine goes through it's "vacuum" stageas the piston goes up, to suck gas from the carbs, and air thru the flame arrestor. It sucks injection oil out of the rotary valve gear cavity. That oil filled cavity is supposed to be blocked off by oil seals on each side of the gear on your crankshaft, but tends to leak as the seals get old or non BRP two stroke oil is used by the owner. To replace these seals, you must replace the whole crankshaft. Your engine and jetpump alignment is critical to both end seals on the crankshaft, as an engine that vibrates excessively can wear these seals out pre-maturely and allow air into the lower case and cause the engine to run in a lean condition, an engine shut-down, which can result in seizure and failure of the integral moveing parts & internal components like the oil pump and ignition pickup plate or pickup bracket, ect.. Mis-alignment will cause motor mounts, bolts, exhaust pipes to break, and bearings to wear and fail that results in the flywheel jumping around in the magnito houseing tearing up the Stator, starter bendix and anything that gets in its way as the motor revs.

 

[seadoo/skidoo]

ok thanks bills86e i will do a leak down test next time im at my cottage :cheers: