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93'XP
12-08-07, 08:10 PM
i just got a 93 seadoo xp with a 657 motor, the guy said it had been recently rebuilt, is there any way i can prove this, what should be the compression on a newly rebuilt 657 motor? 180psi?

kustomkarl
12-09-07, 12:00 AM
If the guy you bought it from had it rebuilt recently...ask him for receipts. This way you know exactly what was rebuilt. Compression should be 150psi per cyclinder. Anything below 90psi could mean trouble. To take a compression check correctly, if the engine runs, warm up the engine. If on the trailer use a garden hose, so as not to over heat things. Get the engine warm. Shut it off, turn off water. Remove the spark plugs and plug the sparkplug caps on the ground plugs. Insert the compression gauge in the first hole. Hit the starter roll it over about 12 times or until the compression peaks. Do each cylinder to get a correct reading. They should all be fairly close in PSI. If you have any more questions let us know, and I'm sure you'll get an answer.
Karl

93'XP
12-09-07, 05:04 PM
i own a compression guage kit, the guage read 175psi in each cylinder back when i first got the ski, it looks like it has been rebuilt because you can see the cylinder gasket sticking out, also when i had the whole exhaust system off i used a mirror to look into the exhaust ports and they looked great with no scaring or scaped on the sides of them, so that good news

another thing, when i had it running for a bit it smoked alot(blue=oil), and the gas smells like it might be mix, could this be from the initial break in period since it sounds like it has been rebuilt recently

kustomkarl
12-09-07, 05:19 PM
Well, It sounds like you engine is in good shape. If the compression is 175 psi than the internals should be ok. Unless you have a receipt or some kind of paperwork you will never know what was exactly rebuilt...maybe just the head gasket was replaced... it would be hard to tell unless you tear it down and check the free end gap on the rings and the carbon build up on the pistons. Usually extra 2 stroke oil is added to the fuel during break-in, so it will be well lubericated. Enjoy it and change the spark plugs after break-in tank of fuel. If you have any other questions give us a shout.
Karl

seadoosnipe
12-09-07, 07:39 PM
It is possible the smoke is coming from break-in. During break-in of a newly rebuilt motor, the mix is about 24 or 26:1. This will cause a little smoke. If your using premix and not the tank, then you should be using a 50:1 ratio after the break-in period. If your using the injection system and tank, keep an eye on how fast you use this oil. If your oil level has a good drop, then it's possible your rotary chamber seals either didn't seat or weren't replaced. If this is so, then the oil from the chamber will bleed into your combustion cylinder and burn off in the engine, creating heavy smoke. On average, that oil tank should only need to be refilled once a season if your a weekly boater. Daily, you'll use more. Your oil requirements are ......non NMMA type oil. Do not use TCW-3 two cycle oil. Use Seadoo mineral or synthetic oil or it's equivalent. If your not able to get the Seadoo blend, you can use the Quicksilver blend that states it's usuable in the Seadoo rotax engines, which you can find in your local WalMart Superstore. If you don't know what type of oil you are using and have no way of finding out by the previous owner, I recommend you remove the oil and put new oil in, since you can't mix mineral and synthetic. .........:cheers:

93'XP
12-20-07, 03:51 PM
ok after realizing it doesnt take anything special to take the head off, i did, and was surprised it had little carbon build up on the pistons and the cylinder walls still had the crosshatch on it, the pistons had very little to no play if i tried to move back and fourth, i gave some pictures, then i decided to clean everything since i had it off, took some purple power sprayed it on let it soak, wiped it off then when over it with a scotch brite pad, looks new now, by looking at the water passsages i dont think this motor has seen a day of salt water, i couldnt find a bit of corrosion anywhere, i gave some pics too

http://i181.photobucket.com/albums/x122/87stang5-Oh/seadoo%20wiring/DSCF1113.jpg
http://i181.photobucket.com/albums/x122/87stang5-Oh/seadoo%20wiring/DSCF1112.jpg
http://i181.photobucket.com/albums/x122/87stang5-Oh/seadoo%20wiring/DSCF1114.jpg
http://i181.photobucket.com/albums/x122/87stang5-Oh/seadoo%20wiring/DSCF1115.jpg
http://i181.photobucket.com/albums/x122/87stang5-Oh/seadoo%20wiring/DSCF1116.jpg
http://i181.photobucket.com/albums/x122/87stang5-Oh/seadoo%20wiring/DSCF1124.jpg
http://i181.photobucket.com/albums/x122/87stang5-Oh/seadoo%20wiring/DSCF1123.jpg
http://i181.photobucket.com/albums/x122/87stang5-Oh/seadoo%20wiring/DSCF1122.jpg

kustomkarl
12-20-07, 05:36 PM
Did I miss a Post? You pulled the head off the engine why? Does the seadoo have a problem or are you just checking things out? Remember the old saying.."if it ante broke don't fix it..."
Karl

93'XP
12-20-07, 07:46 PM
no you didnt miss anything, i had a seadoo mechanic say well you could pull your head off and look at the cylinder walls to tell of its been rebuilt recently, so i did, it took me all of 10min to pull the head off, and i was bored

dieselman
12-21-07, 06:58 AM
Well if you are still bored you can wash my truck lol just make sure you use a new head gasket and tork the head bolts in a criss cross starting from the center out to the manufactures spec's:rofl:

kustomkarl
12-21-07, 08:23 PM
Uh, if you were bored, why didn't you go riding, rather than wrenching? That's where I'd be! It is 80* here in Florida water temp is 72*. I'm not sure where Belleuve is. If it is warm and the water isn't frozen...then go have fun!:)
Karl

93'XP
12-25-07, 01:05 AM
Uh, if you were bored, why didn't you go riding, rather than wrenching? That's where I'd be! It is 80* here in Florida water temp is 72*. I'm not sure where Belleuve is. If it is warm and the water isn't frozen...then go have fun!:)
Karl

yeah i would have been out there but it was about 34 degrees and raining

kustomkarl
12-25-07, 09:48 PM
Yecks 34* is kinda cold to really enjoy the water. I'm originally from Upstate N.Y., where it gets cold from late October to about late April. It is tough to just look at you machine when it's that cold, cause all you want to do is tinker with it and the wind is blowing... Where is Bellevue anyway? You really might want to join as a premium member so as to have some good reading materal on you doo. Check out the link at the top of the page under "seadoo manual" for info. It just might help you get through the long cold season.:)
Karl

93'XP
12-26-07, 01:26 AM
its in washington, 13miles away from seattle(by the waterfront), and we even had a white christmas(snow on the ground)

kustomkarl
12-26-07, 10:48 AM
I miss the white christmas with snow and all, but I really enjoy the warm weather here year round more. We have white stuff here too like you ...but we call it beach sand! Hope you had a great Christmas.
Karl

seadoosnipe
12-26-07, 04:38 PM
Wow, it's been many years since I was out your way. I got family in Washington.
I lived in Portland for a couple years, learned to ski on Mt. Hood at Timberline. I must say about the only thing I miss of the snow is the fun sking down a fast slope and warming up with an avalanche drink in the bar after the run. Come to think of it, I spent more hours in the lodge than on the slopes!..........:rofl:

93'XP
12-27-07, 06:37 PM
yes, i like the snow too, in the past 2days stevens pass got 15inches of snow, thats where im headed this weekend