from this thread
http://brentroad.com/message_topic.aspx?topic=405535&page=1

so we have 2.
1996 XP
1996 GSX

1 runs (last i remember)
1 needs small alum. weld patch job.
both could need these, or one needs the patch, one runs. i dont remember.

so.... i will attempt to work on these myself, of course swapping plugs out and trying to crank them.

i remember one of them stopped running after running up on a sand bar, but i dont remember if we got them back running. this was last year, or more.

[Edited on April 27, 2008 at 1:56 PM. Reason : ]

4/27/2008 1:55:15 PM

ok so i looked at them.. and i think the one with the patch job, also has an oil leak.

there are puddles of oil in the engine bay. i tried to source the leak, but im thinking its from under the motor. do i have to pull the motor and put a new one in there?

4/27/2008 5:47:46 PM

I need someone to look at a '99 Yamaha XL760, I think its def something with the electrical system or computer, my brother tried to jump it with the battery terminals reveresed...

4/27/2008 6:11:48 PM

if there was any arc, shouldnt there be a fuse?

4/27/2008 6:17:01 PM

^^^

probably the oil pump leaking, its pretty common, the oil injector clogs and builds up too much backpressure

4/27/2008 6:24:41 PM

^^ I wasn't there, but I'm sure something happened. I would assume there is a fuse, but I just didnt even want to look after he told me... what an idiot.

4/27/2008 6:52:02 PM

I'm pretty knowledgeable about the 96 XP, I had one and rebuild the engine in mine myself. Check the oil pump, oil filter, and the lines. Also, convert to premix if you don't want to rebuild it!

Oh, and do not jump it with a running vehicle!

[Edited on April 27, 2008 at 7:00 PM. Reason : .]

4/27/2008 6:59:49 PM

^ yep bye-bye ignition and voltage regulator

4/27/2008 7:10:13 PM

he didnt use a car, he used a battery charger on the "jump" setting...

4/27/2008 7:18:14 PM

which puts out about 16 volts

4/27/2008 7:49:34 PM

^ so is that better or worse?

4/27/2008 9:45:51 PM

just as bad I'd say

4/27/2008 9:47:13 PM

anyone recommend any shops to do performance engine rebuilds/pump setups? anywhere from the triangle area down to the coast is fine.

4/27/2008 9:51:53 PM

i might have a name or two. my brother passed by some shop and im trying to get the #.

we took it to a shop last year or whenever my last thread was made. after we got it back, they closed up shop. which sucked

4/27/2008 10:38:48 PM

I think you are in over you head with these older doos...I used to be a mechanic a few summers ago for Performance Watercraft in Wilmington. You will fix these and then keep fixing these for the next five years, and they will keep on fucking up. Of course we ran ours in salt water, so if your in freshy then u r better off.

I'd say get newer ones, but if it's a hobby of yours and you wanna fix em up then, do away with the oil pump on the one, and pre mix like suggested before. That way you will have fewer problems with the pump and you are guaranteed not to scorch your shit. Make sure the case and jug are good to, you mentioned you needed alum welding done, not a good idea from experience, need to replace if it has a damn hole in the engine...

4/28/2008 4:13:28 PM

^^^ watercraft solutions in Wilmington, will put whatever shit you wanna on and has some killer stuff as well.

4/28/2008 4:17:50 PM

oh snap. ill look into them. we use the skis in carolina beach, so they will be convinient

4/28/2008 4:28:12 PM

^ yea I think he is still in business, we were working on a bunch of older yamaha's that he had. We fixed and modded about 3 or 4 1999's 700's and 800's. They were really fun, but beat up. The tourists are mainly the ones who rent from him, and they always fuck them up...countless times I can remember blowing sand out of the engine and then rebuild because we had many times when compression ~ 0

4/28/2008 4:32:58 PM

SBT!!!!!!

4/28/2008 4:34:08 PM

y0, so one of our jet skis hit a little sand bar during low tide.. what typicaly could go wrong?

im gonna be doing some of the oil work that was mentioned in this thread. but i wanna know if i should even bother. or just rebuild it.

4/28/2008 4:40:06 PM

^ 1st thing is salt water destroys jet skis if they are not properly flushed out EVERY SINGLE time that the are pulled out of the water. When you pull them out flush them run the engine for about 2-5 mins so all the salt is out, then rinse the inside of the hull and engine with fresh water being careful not to get any in the carbs.

Typically when a jet ski hits a sand bar it stirs up muck and sand and if you let it run on top of the bar for just a split second all that crap gets sucked into the cooling system. The intake should be right near the pump in the back of the ski. Usually it gets all clogged up and water can't flow properly. This causes the engine to overheat thus scorching the cylinders and making the walls of the cylinders "unsmooth," so to speak, which in turn means loss of compression and then your engine is history!

What you need to do is get a compression tester and test the compression of each of the cylinders by taking out the spark plugs and put the tester on only ONE of the cylinders, then turn the engine over a few time and see how much compression you get. If it is good then your engine is fine. If it isn't then you need to get an new engine, better yet don't waste your money on a fuckin Doo and buy a Yamaha!

But hey if the engine is good then your golden, just get it to crank up, put the flush kit on it, and run some water through it for about 5-10 mins. You should be able to put your hand on the engine and keep it there for about 10 seconds. It SHOULD NOT be running hot. If you have to pull your hand back really quick then there is a problem and you need to blow out the cooling system.

Let me know if that helps and if you got anymore Q's let me know.

4/28/2008 6:15:18 PM

very nice. yeah, ill check the compression.

ill do that first.
i also need to find where the oil is leaking from.


well these sea doos were my uncles. he picked them up a few years ago and pretty much gave them to my brother and as long as take care of them. well we took them to someone to get ready to drop in the water, and they worked. i cant remember what happened, im thinking the sand bar caused one of them to cut off. so we've had them sitting ever since. almost a year.

4/28/2008 6:33:17 PM

also check the bottom of the casing of the one that was leaking oil, sometimes they over heat, the piston "explodes" and the rod goes shooting through the casing and oil and gas go everywhere. You should have heard a loud bang though if that were the case.

It sounds like they were in good condition though if they were both running a year ago, the worst thing to do is neglect them then you have all sorts of problems. Start them up every few days when you get them fixed. It's kind of like a car in some sorts.

new batteries might be needed as well...get the dry cells!

4/28/2008 7:01:15 PM

how normal is this? the automotive part says its not a good sign, but the fact that these things run in salt water/sand perhaps is somewhat normal (but a little un-normal)






the first pic is of the flange where exhaust manifold meets whatever
the second is where exhaust manifold meets "muffler"
the last two pics are of the exhaust manifold, i guess thats what it would be.

4/29/2008 8:43:08 PM

looks normal for ocean going skiis

4/29/2008 9:08:49 PM

yeah ok.

thats kind of what i figured.

4/29/2008 9:30:25 PM

Yea that's not too bad, just salt build-up due, needed more flushing, but just make sure there is no bad corrosion. But other than that, I've seen way worse.

4/29/2008 9:49:31 PM

ok, so i looked around the oil pump and it doesnt seem to be leaking, i even took it apart, doesnt link.

the lines look fairly good.


i took the valve cover/cyl head off and the pistons and walls look/feel normal.

how many oil lines run under the motor? i think there are like 3 main oil lines and i traced all of them and felt around and didnt feel anything.

i may just try to get it running and see if that causes it to leak or anything.

4/30/2008 6:21:01 PM

yeah, that's not great but not terrible for a 12 year old machine that's spent a lot of time in salt water.

i think this is the first thread i've seen coherent advice from shredder. definitely accurate info. especially the part about selling it and buying a yamaha.

as has been mentioned, do a compression test or at least look at the plugs. hitting sandbars, running completely out of the water, etc. can all really hurt a motor in more ways than one. overheating and over revving most commonly. that's how i killed the first motor in my gp1200. lots of full throttle with the intake completely out of the water. stretched a connecting rod and the piston got friendly with the head, lol.

oil in the hull isn't terrible unless it's definitely coming from the engine. could be just as simple as it getting spilled out of the injection tank or a line leaking. a lot of people soak/coat their engines in oil or lithium grease for salt environments also and it will eventually run off onto the hull.

as for shops, there used to be a good guy on yonkers rd. i can't think of the name of the place to save my life, but i can tell you exactly where it is if you want. i don't know if he's still in business. he did the machine work and assembly on my shortblock and then tuned it after it was back together. it wasn't cheap (nothing relating to any watercraft is though) but he did good work and it screamed after he got the carbs dialed in.

4/30/2008 6:56:26 PM

Quote :

"lots of full throttle with the intake completely out of the water. stretched a connecting rod and the piston got friendly with the head, lol."

did i show you the pics of mine?

#2 cylinder seized, and unseized when it cooled..repeat about 10x... it was f'ing nasty

4/30/2008 9:06:08 PM

i found this site.

http://seadooforum.com/showthread.php?t=437

i already checked the lines. but ill look at them again with more light.

thanks for the info guys.

4/30/2008 9:18:14 PM

Quote :

"i also need to find where the oil is leaking from."

most likely from the oil tank... i'm sure you know 2 stroke engines dont have oil in the crankcase like a 4 stroke so besides a line, oil pump or oil storage tank there really aren't many other places it can come from

4/30/2008 9:33:36 PM

well the oil tank is clean. but yeah, maybe the lines are rotted, i couldnt tell today.

anyone good with matison motorsports? i emailed them. they said they work on pwc's.

i just wanna get these back on the water.

i gotta charge the batt. and throw it in and see if it starts up.

4/30/2008 9:37:23 PM

matison has a really bad rep.

4/30/2008 9:47:33 PM

oh snap.

thanks for the heads up. sending to a shop was my last resort.

ill probably try to stick to somewhere around wilmington/carolina beach

4/30/2008 10:27:03 PM

^ yea replace the oil lines I would think make sure they are all tight connections...There isn't crack in the jug or casing is there? I'm not sure if that is the one that overheated or not...

4/30/2008 10:35:01 PM

well i slipped my hand under the engine and i felt sludge on the hull, but not the engine, its water+oil sludge from that 2 days or hard rain we got. there is sludge under the engine, and towards the back of the hull its oil.

i dont know why i didnt take any pics.

i tried to feel around for any noticeable cracks, didnt find much. but obviously its gonna be hard to feel them.

i need to use a mirror. ill get back on it either today or tomorrow.

5/1/2008 10:07:58 AM

the yellow circles are where the oil build up is. under the gas tank there is a small small trail. i think it may have came from there, but i dont know.

5/1/2008 5:35:42 PM

when we had a ski back in teh day, my dad pounded it in my head that every time i was done riding, salt or freshwater, to pull it up on the pier, run the hose down, hook it to our little hose bib connection we made to go into the engine's intake, and flush it out with fresh water for about 10 minutes

only other issues i ever had were if we accidentally ran over a little marsh which clogged the impeller...but thats easy enough to take care of, just stick your hand inside the impeller while you're in the water (and the ski is powered off obviously)

5/1/2008 5:42:35 PM

I've always seen oil in that same spot on my Sea Doos. That's one of the spots where those missing nuts and bolts from batteries and whatnot end up after a ride and you always have to fish through the goo to find them. No idea where it comes from, but I wouldn't worry about it. Just hose it out and see if it comes back worse.

I'd go ahead and put in an oil injection blockoff. It's like $15. Those old oil pumps go bad all the time. Nylon gears ftl.

You never did say what it's doing or not doing. Does it turn freely? You should be able to pull that boot back and turn the impeller shaft to see if the engine is locked. Does it turn over? Compression?

Make sure the water passages through the exhaust pipe (those outer channels on the exhaust) are flowing freely. That is your water intake and if they're clogged it'll overheat pretty quickly. Make sure the water exit lines flow freely as well. It should run from the head to a little jet (or pair of jets) at the rear of the ski where the water exits. Just disconnect the water line from the head and try to blow through it.

[Edited on May 1, 2008 at 6:23 PM. Reason : l]

5/1/2008 6:21:16 PM

see, thats the thing. i pulled that plastic cover off yesterday and tried to rotate the shaft,it was real damn hard... with the plugs out it was obviously easier. but dang.

so today i hooked some power up to it. and tried to turn it over. with both plugs in it barely turns over, actually, it doesnt, it acts like its stuck... even with one plug out it does the same.

with both plugs out it turns over rapidly like (i guess) normal.

i hooked the compression tester up to it, it was hard to get a reading, but it didnt even do a correct stroke, it was all nasty sounding, but each cyl. got 70 psi.. but thats with the other plug out. im thinking something is up with the internals. sounds like a siezed component when the plugs are in, but when they are out it sounds normal.

[Edited on May 1, 2008 at 6:41 PM. Reason : ]

5/1/2008 6:27:42 PM

Quote :

" running completely out of the water, etc. can all really hurt a motor in more ways than one. overheating and over revving most commonly. that's how i killed the first motor in my gp1200. lots of full throttle with the intake completely out of the water. stretched a connecting rod and the piston got friendly with the head, lol. "

it didn't have a limiter to keep it from over-revving every time you come out of the water? i think my Ultra did, although I don't remember for sure. seems like it would be a necessity on a ski like that--I know I spent a huge percentage of my time with the hull out of the water.

5/1/2008 6:44:33 PM

wo ho ho, you only got 70 psi??? that doesn't sound right to me...What size is the engine, I'm not sure about doos but mine gets about 130 in each cylinder.

Urs is two cylinder right? 3 cylinder should be a little bit lower.

5/1/2008 9:01:02 PM

baonest check this site for how to do it, unless you have done that already.

http://www.pwctoday.com/showthread.php?t=62279

5/1/2008 9:03:38 PM

yeah. ill try it again tomorrow.

i cant do it with one plug in and the tester in the other hole. the motor wont even turn over.

that is what is puzzling.

5/1/2008 9:11:00 PM

i'd just pull the head off and see wtf is going on.. something def isn't right internally if it's that hard to turn without the plugs in it.. it should be damn near doable by hand

5/1/2008 9:16:22 PM

well without the plugs its easy to turn. but even with one of the plugs is it gets significantly harder. and with both plugs it takes some muscle.

5/1/2008 10:50:05 PM

It should get hard to turn with the plug in...That's how you know you have at least some compression. But you know this already so I'm guessing something must be really odd. I don't know the factory numbers, but I'd think you'd need at least 115+ psi or so of compression for it to fire. If it's turning over really slowly you're probably not going to pump up the compression gauge enough to get accurate results.

You said there was no notable damage to the cylinder walls, so maybe your crank bearings are shot? It can't be that many things. Seems like either you don't have enough juice in your power source, your pistons are binding (or aren't being lubricated!), or the crank bearings are shot. Maybe the rings on the pistons rusted up and they are binding?

Have you tried jumping it with a non-running car battery? At least that way you know you're getting enough amps to turn it over. I guess the starter could be weak, but usually the starter clutch goes out or the motor in the starter just dies. Never seen one that was actually "too weak" to turn the motor over.

5/1/2008 11:32:06 PM

^ correct

5/1/2008 11:52:04 PM

my Ultra also made about 130 psi in each cylinder, if i remember correctly

5/2/2008 12:37:10 AM