2000 Seadoo GTI - Crank Damage?

[x17andrew71x]

Happy May the 4th!

This is my first time posting, been reading everything I can here, but I am stuck... Or rather the ski is stuck...

I bought a pair of these skis a few weeks ago, one started right up. This second one not so much.

It has been a long process of one thing after another, and I'm not sure what damage was there already and what I've caused... but from the beginning: it would crank like maybe 2-3 turns and stop then emit a single beep. Like if the battery was dead. Got a new one, charged the old, jumped it, all with the same results. Checked all grounds, fuses and wiring and cleaned them all along the way. Finally I pulled the starter, didn't seem to click out, only spin, so i replaced it and it would turn over! Awesome!

Then in my excitement to try and get it started, i didn't think to check the tank, bone dry... also, for reference, they previously bypassed the oil injection and ran it pre mixed.
I got the other ski with a half tank gas, just figured this one was the same, didn't even glance. So it wasn't starting, grabbed the starter fluid, gave it a good shot and it fired up and ran on that for 2-3 sec till it burned it off. Did this a few times. My thoughts were, ok it has got the bad gray fuel lines, carbs are probably clogged from sitting and those lines. So i left it.

Next day i pulled carb and replaced lines, heres where i noticed bone dry fuel filter and then tank, added premix and tried to start it but get a single hard thud, like it tries to turn but stops right away. I can't turn pto by hand, pulled the pump off the back of the ski, which spins freely, pto no change. Removed starter in case i burned it up and got it stuck with too much cranking, starter is fine... still only budge 1-2 inch when rotating pto back and forth. Plugs have been pulled already and i drop a long screw driver in and it moves up/ down about the same amount the pto rocks back and forth.

Sorry for the long post, but the full story i feel is probably pertinent to this one. I am about to try and pull the head off and see if i can tell if it's seized. Is it possible to seize while running for 5 sec at a time with no oil? A handful of attempts? How about from it turning dry with the starter? Can't imagine that would create enough heat?

What else can I look for and or try? Perhaps it's not seized and maybe a bearing locked up instead? If so, what bearing?

Thanks in advance! Your wisdom is appreciated!

EDIT:
Here's some pictures from my opening it up, head bolts were a nightmare... even with impact.
The pistons move freely, but get stuck on something when moving an inch either direction.
What do I look for?

ALSO - I noticed liquid (presumably water) around the piston sleeves? It could partly be wd40, as i've been going crazy on the head bolts, almost a whole can, but this seems like more than a can of wd40's worth. Is that normal/bad? It probably has been sitting in there for months if it's water... What damage if any would this cause? Is it contained or a cause for concern?

 

[x17andrew71x]

Well, I took the top end off, and saw a little piece of broken copper it appears sitting on a little notch to the side of the rear (stern) piston. That piston seems firm and hard to move at the crankshaft end, piston head side is fine. Does anyone know what part is copper within the bottom end and that would seize up the piston arm? The front (bow) piston moved freely and with little resistance. There is a little bit of bow-stern (side to side) movement in the piston arms, is that normal?

Sorry if I am not clear enough, trying to make sure I use as much explanatory language as possible, I am not 100% sure on every part name in the engine, I get the basic concept of most motors, but my terminology is poor...
I am halfway thru the process of removing half the motor at this point, so I am likely going to just complete that process and do I can split the case and assess the damage fully. What would have caused this to happen and how can I avoid it? Now that I will have the engine out, what should I do maintenance wise to get more life out of the motor and get it to be as good as I can before I throw it back in?

I would appreciate any and all guidance, just kinda flying blind here...

 

[mikidymac]

Most people don't have a clue on these and think premix is the cure for everything.
These engines have a rotary gear that rides on the crank and is supplied oil from the oil injection tank. Once you remove that oil supply the gear seizes and stripes out locking the crankshaft. Typically the first thing I think when it seizes using premix.

At this point your only option is to pull the engine, remove the cylinders and split the cases. Make sure you remove the rear PTO flywheel before pulling the engine.

 

[x17andrew71x]

Most people don't have a clue on these and think premix is the cure for everything.
These engines have a rotary gear that rides on the crank and is supplied oil from the oil injection tank. Once you remove that oil supply the gear seizes and stripes out locking the crankshaft. Typically the first thing I think when it seizes using premix.

At this point your only option is to pull the engine, remove the cylinders and split the cases. Make sure you remove the rear PTO flywheel before pulling the engine.

Thank you for this insight, lovely to hear... Both Skis have been bypassed and I have no idea how long they have been run this way. The other ski runs, so if I can get it converted back to oil injected, do you think it would be okay, or should I pull it apart to inspect for damage?

As for this one, I do plan to pull the engine and take care of it, I believe without pulling it apart yet that the bearings on the crankshaft sandwiching the piston arm are shredded on the stern piston...
So if the rotary gear looks okay while disassembling, would it be okay to leave it and just get the oil injection set back up on it?

Do these not get any oil from the pre-mix at all? Or just simply not enough?
It looks like the entire oil system has been bypassed and partly removed on both skis, what do I need to get them both set back up from nothing?

EDIT:
Also, why is removing the PTO necessary before engine pull? I heard it requires special tools? How do I remove the driveshaft/PTO from the bottom end properly before removing the rest of the engine?
THANKS!

 

[1of500]

It's damn near impossible to remove the pto out of the hull

 

[x17andrew71x]

It's damn near impossible to remove the pto out of the hull

Ok, so how do you from within?

 

[1of500]

Chain wrench or impeller tool

 

[x17andrew71x]

Chain wrench or impeller tool

Thank you, I have a chain wrench. Guessing it's standard counter clockwise when facing the front of the ski?

Do I need to do/undo anything prior to wrenching on it? Or can i leave the driveshaft and everything connected? If not, how does that come undone?

 

[1of500]

You will need to remove the pump and drive shaft. Might help if you download the manual.

 

[x17andrew71x]

Okay, I will have to pull it out tomorrow, any tips for cracking the case, things to do/not do. As well as how to remove everything from the crank properly to replace the bearings and whatnot? Good kits for buy for the rebuild?

 

[mikidymac]

You will have to put the pump back in to remove the driveshaft stainless hat for the carbon seal. Then the driveshaft will pull out the back of the ski.

You will need a block of wood or rope in the rear cylinder to lock the engine to remove the PTO flywheel with standard threads.

You can't rebuild the crankshaft yourself, you will have to get an already remanufactured one.

 

[etemplet]

Take your time, pause, read, ask questions as you go. I've been using a 1/2" impact wrench to remove the PTO and Mag Rotor. Sometimes they need heat, sometimes spin right off. I'm always curious about the chain wrench removal procedure. Good Luck !!

 

[x17andrew71x]

You will have to put the pump back in to remove the driveshaft stainless hat for the carbon seal. Then the driveshaft will pull out the back of the ski.

You will need a block of wood or rope in the rear cylinder to lock the engine to remove the PTO flywheel with standard threads.

You can't rebuild the crankshaft yourself, you will have to get an already remanufactured one.

Thanks for this, to make sure I understand fully:
The stainless hat being the inside the ski portion that seals the hull that the driveshaft goes through? Why does the pump need to be in to remove that piece? And what is the carbon seal?

Where do you recommend I purchase one from? Sorry for all the questions, new to this. Decent with mechanics but not the ins/outs of a ski. I saw somewhere that someone was able to replace the bearings/seals on a crankshaft, is this not doable with this particular ski?

So at this point I am looking at ordering:
- Crankshaft
- Top/Bottom head gaskets

What else am I missing/should replace if I am at this point already?
Thank you!

 

[x17andrew71x]

Take your time, pause, read, ask questions as you go. I've been using a 1/2" impact wrench to remove the PTO and Mag Rotor. Sometimes they need heat, sometimes spin right off. I'm always curious about the chain wrench removal procedure. Good Luck !!

I won't have the time until mid-day tomorrow to dig into it more, but I will try all of this. I definitely prefer to have as much of the picture and procedure figured out before I get into it. Will for sure stop and take a break if needed.

Love to get the little tips/tricks from people who have done this work before and who know their way around these skis well. Definitely helps! I do have a 1/2" impact, but it doesn't seem like there is any bolt present to wrench on? Is a special tool required?

 

[mikidymac]

Don't order anything until you get it apart.
No, you can't replace the bearings on these yourself or any watercraft crankshaft since you have to split the webs and realign.

Yes, the stainless hat is inside the ski. With the pump out you have nothing to hold the driveshaft to push the stainless hat back enough to expose the locking clip that holds it in place.

Download the service manual for free.....

 

[x17andrew71x]

Don't order anything until you get it apart.
No, you can't replace the bearings on these yourself or any watercraft crankshaft since you have to split the webs and realign.

Yes, the stainless hat is inside the ski. With the pump out you have nothing to hold the driveshaft to push the stainless hat back enough to expose the locking clip that holds it in place.

Download the service manual for free.....

Yes, I agree, no ordering until 100% on what to order.
Thank you, I understand better now about the crankshaft.

My hat looks glued in place with some thick gray stuff, what will I need to replace it with in order to have a good strong seal?

 

[mikidymac]

Nothing should need to be replaced and there should not be any glue.

Post some pictures.

 

[x17andrew71x]

Nothing should need to be replaced and there should not be any glue.

Post some pictures.

I will when I get home in a few hours, how does it seal from water intrusion?

 

[mikidymac]

2 o-rings under the stainless hat and the stainless hat riding on the carbon seal. If you are in the water and pull back the carbon seal/black accordion boot water will rush in.

 

[x17andrew71x]

Here's what we're looking at (attached pics)

My guess is the hat being on the back of the ski, and the carbon seal and lock washer are behind it? Does look like some gray/black glue behind it doesn't it?

What needs to be done on the inside for the driveshaft removal? Loosen up these boots and that's it?

 

[mikidymac]

Put the pump back in the ski.

The stainless hat is circled in red and needs to be pushed to the rear of the ski, see red arrow.

This will expose the C-clip (yellow line) then remove the clip.

Now you can pull the pump and driveshaft out the back of the ski.

 

[x17andrew71x]

Put the pump back in the ski.

The stainless hat is circled in red and needs to be pushed to the rear of the ski, see red arrow.

This will expose the C-clip (yellow line) then remove the clip.

Now you can pull the pump and driveshaft out the back of the ski.

Thank you!
I will get this done tomorrow, do you recommend leaving it in place for the PTO removal, or does it get in the way?

 

[mikidymac]

No, you need to remove it before messing with the PTO.

 

[x17andrew71x]

Alright, so here's an update:

Took the PTO off with the chain wrench, buggered it up real good, it's just paint right, can I sand it down and repaint it?

Pulled the motor out and started disassembly. Got to the rotary valve and as I pull the cover off, another copper bit falls out. The valve plate, or shim, not sure what it's called... that part is perfectly fine. Looks good, feels smooth. The case behind it though has a groove worn in by the copper piece riding behind it... Will this groove become problematic? Does it matter for functionality?

Alright, proceeding onward, cracking the case, it looks like it's been opened before? Has some form of sealant on it. Upon looking at the crank parts, bearings, etc. It all looks decent, bearings spin well. Only problem is the thrust washer between the piston arm is shredded on one side... causing the arm to sieze up.

I noticed also that under the crank, the rotary gear I believe it would be called, is shredded pretty good on a portion of it. The crank side is unaffected and good.

Lastly, one piston, the upper rod and pin bearings came loose easy, other side needed to be influenced to be removed, lol. One looks good, a small line or two, the other is not so good... pretty scratched up, does this matter? Or is it just the cylinder wall that matters? Because that's where the rings sit against.

The cylinder sleeves look fine, smooth, except for the top little portion on one.. I believe this is from me leaving the head off for a few nights... and dew settling on it... It was covered with a canopy above it, so U didn't think about it, never rained. Just had it for shade. Can I just rehone it to clean it up?

Oh last thing... sorry, I know it's alot... Under the problem piston arm, on the bottom of the crankcase, there is a groove for the piston to ride in and not touch, it appears more copper debris was run between them causing more groove worn in. Does this matter, can I just sand to make sure there is not going to be any unwanted contact?

Thank you for your insights and sharing your wisdoms. You all are appreciated!

- Andrew

 

[x17andrew71x]

I forgot to mention this as well, on the cylinder there was a small chunk broken off. Is this going to weaken the cylinder? Or is it not that big of a deal?

In the picture with the two cylinders, you can see it on the top right inside.

Please let me know your thoughts.