98 SPX project

[JDC]

Hey, brand new to site. I have had 2 doos in the past, and now have a project. It is a 1998 spx 800. (787). Anyway, picked it up cheap. Woman had let it set for 4 yrs, her new man tried to get it going, put a new starter, something in the pump (she didn't know what). The engine won't turn according to her. The ski is in prime condition. Engine compartment is very clean, factory paint is sill on all the bolts, so I know that no one has broken into it.


My question is this, I am going to pull the motor, friend is our shop mechanic, (polaris man) and he will help break it down to see what is needed, and then help me put it back together so I can reinstall. What might I be looking for? Is there something that I could check to see what the problem might be?

Are Pro-x pistons worth the money over WSM?

Thanks for the help.

JD

 

[timmyboy76]

before pull'n the motor, pull the plugs, and jump the relay, see what happens, if nuth'n, then remove pto cover (grey color) and turn pto, if its not smooth turn'n, then motor is locked, or pump assy locked...

 

[JDC]

Alright, I am totally new. I understand the PTO, (the output shaft motor to pump?). That won't turn. I am not certain what relay you mentioned. I have had skis in the past, but never had to do much more than routine stuff.

Gal I bought it from claimed it just had pump work done, so I that is what leads me to believe the motor is seized. I was hoping that I could ease rings away from the cylinders and put a new set it. I hope that they are just stuck, and did not get that way from getting hot, just that it has not been ridden for 4 years.

Anyone had such good luck with this?

I know I will more than likely go with a new top end, based on what I have read and been told.

Thanks for the input.

JD

 

[timmyboy76]

if there is a way, you can find out, if the ski ran "after" the pump assy rebuild was done, that would be beneficial to you. Reason being, if pump was done, slapped on there, then decided to park ski for 4yrs, maybe pump wasnt put together right( smashed the bearings) and that would still cause the motor not to turn.
IF pump ok, then go to auto parts store, get can of PB-Blaster, pull plugs, spray that crap, down inside holes, and let sit a day/2....stuff is amazing. If still jammed, then either, pull pump and turn motor, or pull motor.

 

[JDC]

That is exactly what I was hoping somebody would say. Gal I bought it from said that they could not get it started, so her then boyfriend put a new starter on it. Then years (?) later new boyfriend had pump worked on, still no go, and has sat since (more years?). She claims the whole process took 4 years, however the tags are from 02, so that would put it a little past 4 years. Super vague on what exactly went on, but she seemed sad when it left, she said she knew we would get it running and made us promise to take her out the first trip. I almost doubt that she ever ran it, I will be curious to see the hours on the ski.

I though I might take the pump off, then try to start it, just to make sure I didn't have to pull the motor unless absolutely needed.

Thanks a ton. I will get to it some time this weekend, I have to work on the backyard fence for the wife first, then my new toy!

Again, appreciate the help

JD

 

[robin savell lloyd]

That is exactly what I was hoping somebody would say. Gal I bought it from said that they could not get it started, so her then boyfriend put a new starter on it. Then years (?) later new boyfriend had pump worked on, still no go, and has sat since (more years?). She claims the whole process took 4 years, however the tags are from 02, so that would put it a little past 4 years. Super vague on what exactly went on, but she seemed sad when it left, she said she knew we would get it running and made us promise to take her out the first trip. I almost doubt that she ever ran it, I will be curious to see the hours on the ski.

I though I might take the pump off, then try to start it, just to make sure I didn't have to pull the motor unless absolutely needed.

Thanks a ton. I will get to it some time this weekend, I have to work on the backyard fence for the wife first, then my new toy!

Again, appreciate the help

JD

Even if it seized from rust be very carefull taking it apart to salvage the parts so that you will have a good core. It can be done but may be a spray with penatrating lube and wait type of thing. Could even require a press. Each part that you damage is close to $ 100.00 or even more as a core. I can always be wrong so good luck. Robin :cheers:

 

[JDC]

I have been along the same thought. I want to go slow, re-sleeve the pistons is about $100 from full bore. Their kit (with boring and new pistons rings) was the route I am leaning towards once I figure out exactly what is going on. Does the bottom end of the motor get it's oil from the tank? If so, then there is still oil and for that matter gas in the tanks.


Anybody done a top end with full bore? What pistons would one go with?

WSM, WSM MOLY, Wiesco, or pro-x

I don't know the difference, but I will venture to say that wsm are a china type knock off?

Thanks

JD

 

[ppandr]

Start by pulling the pump off. This should take only a few minutes. I would want to check the status either way since you have know idea what line of crap she fed you. I agree to soak the motor top end. Be prepared to replace the jugs either way once you start taking the head off. The stainless bolts will not come out without snapping a few off....and then try to get the studs out. If it was not run for so long there is a good chance that it's just locked up from sitting.

 

[JDC]

Pulled pump off. Impeller is Brand new! Still has Made in Taiwan sticker as well as part number sticker on it. Wear ring is new as well.

Cone had new oil, but the cone itself got way to hot at sometime, it is melted around the edges. I don't know why they put this back on.

I have the cylinders marinating in penetrating oil till Sunday night, then I will try to give her a jump. Fingers are double crossed.

Thanks again, will keep updating the progress.


JD

 

[JDC]

Was checking the levels of the penetrating oil in the cylinders, and the rear one seems like it isn't holding fluid.

Am I to think that the rear piston is busted, causing the oil to leak down?

Maybe a connecting rod has gone out, letting the piston fall?

I would like to see if I could still turn it over with a jump, but now I get the feeling I might do more damage if parts are flopping around in the cylinder.

Anyway advise?

JD

 

[timmyboy76]

with the pump off, good jod btw...remove the spark plugs, and grab the "pto" (round disc under the grey shield) and turn it counterclockwise. Should turn smooth, if so, then pumps to blame for it not turn'n...lets hope thats the case. IF NOT, then let pb-blaster sit a few more days, filling/pooring cylinders up, each day...cylinders' leak'n, may be due to fact the one/both pistons are slightly below the "exhaust" ports, and draining into pipe/manifold. Wou8ldnt worry about that, just get'n ur freed up, main thing...:cheers:

 

[JDC]

Cool, I really appreciate the advise. Was kinda down on the oil leaving the cylinder. I have from the get go had it in my head that I would have to pull the motor, but I would really like to exhaust all options be for doing that.

Earlier you mentioned about jumping it, should I wait and just keep trying to rotate the shaft? How hard would I expect the rotating to be?

As far as the piston positions, the back one is slightly lower than the front. The front oil level has not changed. So hopefully it is like you said, the back one is just at and exhaust port leaking out.


Thanks again,

JD

Here are some pics of the machine, seems like everyone else is posting theirs.

 

[timmyboy76]

Hey bro, thats 1 clean ski, you got there. With plugs out, should be able to turn the pto somewhat easily, feel smooth, with little compression build-up on each stroke....sounds like a damn porno..lol
IF not whats mentioned above, then yeah, leave the blaster stuff soak'n in there, be a bummer too, since motor looks way it does.
Mentioned "front" oil resivoir bottle hasnt changed...thats a good sign, if lower/kept tget'n lower, thats a sign of bad seals, either RV or inner crank seals, or cracked lines...

 

[JDC]

Thanks, figured I couldn't go wrong with $600 for the ski.

I will keep pouring in the blaster on the rear cylinder, so hopefully the front will keep breaking down whatever is holding it up.

I don't know if your talking about the oil tank for the mix/crank? That does still have oil and is not leaking out anywhere, so yeap that is a good sign. Hope that there is nothing on the bottom end that needs attention.

Thanks,

JD

 

[JDC]

Another curious question.

If I remember right, on my previous ski (98 xpl) the pto/output shaft had a special grease that went in for the spline to pto hookup. I thought it was some sort of white lithium grease.

Anyway the grease on the spline into pto on this ski is black, and gooey. Not to mention not a lot on the spline.

JD

 

[JDC]

Looking at the ski, I tilted it back a bit to see if there is any run off from filling the cylinders up with pblaster. It appers that there is. I can't tell if it is all from me missing the hole when filling up, or if there might be something underneath leaking. I have a feeling that it is just overflow, given the amount I have been putting into the rear cylinder.

Is there another area under the engine that I should be concerned about?

I noticed a plug that is down by the crank case by the rear of the engine. Can I unscrew this plug and see what the oil in the case looks like? Maybe some of the pblaster is going in there. I was also thinking about starting the engine pull by taking the exhaust off, that way I might be able to get some kind of glance on what it going on. The pto is still very much unmovable at this point.

I guess I could be more patient, but you know how it is, summer is coming.

Another thing, is there a spanner wrench that can move the pto? I noticed that there are two holes on the pto opposite each other that look like they were made for a spanner wrench.


Sorry so much, I am enjoying learning about the engine, and the whole process has my brain turning, I can't wait to hear the thing run!

Thanks,

JD

 

[JDC]

My bad, pblaster is coming out the carbs.

 

[timmyboy76]

pump off,..cool, motor still not budg'n,...dam-it. Dont worry about the blaster oil, and as for the "screw" down on case, thats where you fill up the "counterbalance" shaft, will NO more than 1oz oil of 30wt. This oil seems to blow by seals, and need checked/re-filled every 50hrs-ish, but some people will say, no need to oil that, it'll get lubed from gas/oil mix...SO.
Know the feel'n, aint got no patience, when it comes to this stuff...but you can use "pipe wrench", grab ahold the "cone" part of pto, and before turn'n, to break loose, may want to remove zerk fitting...

 

[JDC]

I thought the same about trying to turn it. Took the zerk out, might try wed or so.

Our mechanic said to pour diesel or diesel fuel additive down it. He said he freed up a two stroke that way that had sat for sometime.

Don't know, anybody tried diesel?

JD

 

[Chester]

Just take the head off and look inside the cylinders, it'll take 5 minutes. If you see lots of rust, pull the engine out and rebuild it. You can also remove the RAVE valves to look at the sides of the pistons.

Chester

 

[Chester]

I thought the same about trying to turn it. Took the zerk out, might try wed or so.

Our mechanic said to pour diesel or diesel fuel additive down it. He said he freed up a two stroke that way that had sat for sometime.

Don't know, anybody tried diesel?

JD

Even if you free it up, you will still have to rebuild it. If your crankshaft has rust on the bearings, it will come apart by itself. It's just a matter of when.

Chester

 

[JDC]

Thanks Chester,

I wasn't sure how long the head bolts were, so I didn't know if you could take them out with the motor still in the boat.

Also, as far as the bottom end goes, what would cause it not to have oil in it? I mean, even if it sat, would there not be oil in it still? I don't know how the oil system works. I was hoping to stay away from the bottom end of the motor.

Anyway to check and see if there is still oil in the bottom?

My friend, told me that if I do yank the motor out, then I should indeed replace the crank bearings, since I would have it out, and it would suck if these were to go out with a fresh top rebuild.

I will pull heads, and rave valves this week and post what I find.



Thanks,

JD

 

[PWCdoc]

Two strokes don't require an oil bath in the bottom of the motor. If you did indeed have oil puddled up in the bottom you'd be looking at an engine rebuild anyway as the crank seal would be leaking.

If you have any rust you will need a full crank rebuild as it's not a matter of simply replacing the bearings as you would on a 4 stoke with a pressurized oil system. You'll see what I mean when you get it apart.

Beyond this, I agree with Chester.

 

[JDC]

Thanks, I don't have any oil puddles in the bottom, thankfully.

I will stop messing around and get the head of as well as the raves off and see what is inside.

So, rust. Any ideas on how this could have happened? Doesn't rust need moisture/air to develop?

Crank rebuild: What is involved? End bearings? Rod bearings? A grind?

Thanks for all the info


JD

 

[JDC]

Well........ I pulled the raves out wed. night. I was relived that they looked ok. Looked down, and thought, a little rust, not to bad.

Pulled the head this morning, All the head bolts came out great!

Then, relief went to grief.

Well, I now have my work cut out for me. "Let's tear down"

Check it out, and tell me what you think:


JD