1995 Seedoo XP 717cc - turning over PTO by hand is very stiff

[Ebrightstar]

:facepalm:

Hi Folks,

After trying to start my 1995 Seedoo XP 717cc which had been sitting in my yard since 2009 I found the following: The ski hasd been going back in 2009.

The ski would not fire up despite a good battery.

The battery turns the motor over with plugs out but very slow with plugs in.

Used a good 12V19/20A Battery
Cleaned all connections to starter, ground, solenoid, battery etc.

Sometimes when trying to start the solenoid would click and other times the starter motor would activate and turn the motor over without starting.

I removed the jet pump and then tried rotating the PTO coupler by hand (again with spark plugs out) and noticed that it is hard to rotate 360 degrees. It is free then stiff then free then stiff then free then stiff. Although it is very stiff like this with two hands the resistance is not so severe so as to cause a noise or to not turn over fast with the starter motor (when spark plugs are out).

Is this normal or should the PTO turn easier even with hands???

I took the head off and the cylinder lining is perfect as are the top of the pistons. No sign of rings scraping the barrell lining.

So I took the carbs off and noticed that there was oil filled up right above the rotart valve to the top of the intake manifold. I pumped all the oil out with a siphon and tried turn the engine over with my hands and the same stiffness was present.

Is the oil in 'each; side of the crank indicative of the inner seals on the crank being broken or the seal on the rotary valve staft being broken?

Is the stiffness I refer to normal given the fact the rotarty valve joins the crank at 90 degree angle therefore causing greater resistance?

Does the 717 engine have a Bendix gear? or does the Starter Motor engage directly to the Flywheel?

Any ideas and advise would be very much appreciated.

Thanks,

Paul.
Northern Ireland

 

[Lake Sailor]

With driveshaft / pump disconnected and plugs out, the engine should turn freely by hand. Crankcase full of oil usually means inner crankshaft seals have failed.

The starter motor has a kind of overunning clutch w / drive gear attached to the output shaft. When the starter turns, the clutch moves forward to engage the flywheel ring gear, cranking the engine. Engine starts, clutch prevents engine from driving the starter. Start button released, drive gear retracts.

Not sure what to make of your situation, I'm no expert (one will be along shortly, I'm sure). But. I would take it as a bad omen that relieving the oil hydrolock didn't allow the engine to turn freely.

 

[Ebrightstar]

Hi Lake Sailor,

Thanks for the response.

I took the starter motor off to check the condition and to see if engaging flywheel correctly and all was good. The flywheel compartment however was filled with oil from the oil tank.... I cleaned it out and washed flywheel to remove oil residue, put the starter motor back on and put fuel in the night and the ski started.

This is a very unusual situation.... effectively I have motor that goes but may not be usuable given the oil problems leaking into crank and flywheel.

Could this just be due to sitting for 6 years and the fact the oil tank is high up?

And as for the stiffness it does not seem to stop the crank turning at speed when the engine starts....

Any ideas of how I go forward?

Ride it with premix and sufficient oil in hoses to bath the rotary valve and hope the seals work short term as opposed to failing due to sitting for 6 six years.

Or strip it down to identify cause of stiffness and get crank bearings and new seals put onto split crank?

All idea and advice welcome.

Paul.

 

[AdamXP800]

Put in a shut off valve. When not in use close the valve to prevent oil seeping passed the crank seals. Then turn it to on when ready to ride



96 XP800!
Keep the 2 strokes alive!

 

[AdamXP800]

This is not a permanent solution but it will be a patch that should last until you are ready to fix the issue. I know guys that are on their 4th season using a shut off valve on the oil supply line



96 XP800!
Keep the 2 strokes alive!

 

[Lake Sailor]

Ebrightstar, not sure what to tell you. The leaking seal thing is discussed often here, you might do a search for further reading on that. The valve thing is done a lot it seems, there is a solenoid valve some use as well.

I suppose you could run it (carefully) see if the seals improve w/ use. But the stiffness thing is a risk I guess. Do ya feel lucky

As I said, I ain't the expert here...

 

[Coastiejoe]

Crank seal is a very common issue. As noted, most simply install a shut-off valve. So common any more that there are now solenoid based valves that pick up from the DESS and turn the valve on and off when the lanyard it attached.

 

[Ebrightstar]

Guys im confused by the shut off valve?

My understanding was that I was to fill both hoses each side of engine with oil to ensure rotary valve is always lubricated or add a block off plate by removing the oil pump and then run the ski on a 40:1 premix.

Also wud stiffnes on pto coupler be a dodgy bearing on crankshaft rotary valve?

 

[AdamXP800]

Going premix and putting a block off in will not fix this issue. The oil will just drain out of the line and into the engine. Then your line is dry and your have no oil to the rv....... Kaboooom



96 XP800!
Keep the 2 strokes alive!

 

[Ebrightstar]

Ok so do I leave oil tank connected as designed by seadoo and leave the seedoo oil pump in place.

This way I have a plentiful supply of oil.

And dont use premix?

Where and how does the shutoff valve go/help?

 

[Blowncat 509]

go to the "how to" section, it's there i believe...

 

[Coastiejoe]

You will leave the oil tank in place as you NEED the oil even if you do a block off.

You need to install a shut-off valve in the main line that feeds the engine. You will turn the valve off during the times the ski is being STORED.

Anytime that you run the ski, turn the valve ON.

By using this process, you will run you ski just like normal and not have to do a crank replacement. You will get MANY years of use with the setup as I have described it.
They do make a solenoid based valve that uses the DESS to turn it on and off and then you will not have to remember to do it manually.