95 SEADOO SPX issues!

[grss429]

So i bought a 95 seado SPX about a week ago tested it out last week.. only had half throttle/bogging issues.. did a carb rebuild, new fuel lines from the carb, oil lines etc... cranked right up ran for a few mins in driveway fine... full throttle etc.. so i took it to the boat ramp, unloaded started right up... off i went, opened it up and it flew.... went to slow down and turn and i lost all throttle, started running rough got out of the water got home cranked it in the yard... pulled one plug and the electrode was smashed, looked in the hole doesn't appear to have smacked the piston. put a new plug in it same issue hardly any throttle so while it was running, unpluged one wire.. it stalled.. (thats good) started it up and unpluged other wire.. still ran... but was sparking at the wire.. i could hear it

took both plugs out put my finger over 1 cylinder.. great compression.. put my finger over the rear one and hardly any..



so my question is where do i go from here... what are my possibilities


i'm buy a compression tester tomorrow to find out actual numbers.. from what i gather.. no lower then 135 per plug hole

 

[Ralster26]

I bought a 20$ compression tester from amazon and its not very accurate, ppl also say look at how far they are from each other in compression if you think the gauge is janky and not necessarily the reading of max psi itself

 

[MacAddict]

Compression test with a good tester, but by the sounds of it You are looking at new top end at minimum... will need cylinders bored and honed and new pistons/rings... unless the rings snapped and smashed against the head, to which you will need to find a decent used head to replace. You will need new base gasket as well... be sure to retain your old one to know the thickness (will be stamped 3, 4, 5 with circles in pattern like dice) FullBore does great jobs on the top ends, and sells kits with new pistons, etc included

 

[grss429]

Compression test with a good tester, but by the sounds of it You are looking at new top end at minimum... will need cylinders bored and honed and new pistons/rings... unless the rings snapped and smashed against the head, to which you will need to find a decent used head to replace. You will need new base gasket as well... be sure to retain your old one to know the thickness (will be stamped 3, 4, 5 with circles in pattern like dice) FullBore does great jobs on the top ends, and sells kits with new pistons, etc included

how bad would it be to pull the head cover off, and inspect/throw some new rings on?

and ill get some readings tomorrow

also how do i tell what motor i have in this ski?

 

[MacAddict]

Going through the trouble of pulling jugs off just to get new rings in will only cause Murphys law to kick in and cause something catastrophic. Best to go ahead and have bored up/honed. The cylinders could be out of round or taper, or could be glazed over. Who knows what's going on in there honestly. The SPX of that year range was the 717/720 engine from.what I know, and one pf the most reliable 2strokes Seadoo made, but grab a free manual at www dot seadoomanuals dot net .... you'll need it for sure. ..

 

[grss429]

Going through the trouble of pulling jugs off just to get new rings in will only cause Murphys law to kick in and cause something catastrophic. Best to go ahead and have bored up/honed. The cylinders could be out of round or taper, or could be glazed over. Who knows what's going on in there honestly. The SPX of that year range was the 717/720 engine from.what I know, and one pf the most reliable 2strokes Seadoo made, but grab a free manual at www dot seadoomanuals dot net .... you'll need it for sure. ..

i guess ill report back tomorrow with some compression #'s then ill pull the head covers off and see the top of pistons and see if i can find the issue...


my question is if i get the rebuilt kit from fullbore for 285..

Pistons
Rings
Gaskets
Circlips
Upper bearings
Wrist Pins
Your cylinders bored to fit.

am i gunna have more issues?

 

[eavega]

First off, the 95 SPX has a 657X engine, not the 717. Top end rebuild will correct a bit lot of sins, but keep in mind if the bottom end (the crank, connecting rods, etc) is tired, a top end rebuild may stress the bottom end into failure. It's the chance you take. Also, you may want to inspect the pump, impeller, wear ring etc if you pull the pump to remove the engine . Also, verify the oil injection pump is working. A 20+ year old ski will have issues, that is a given.

 

[grss429]

First off, the 95 SPX has a 657X engine, not the 717. Top end rebuild will correct a bit lot of sins, but keep in mind if the bottom end (the crank, connecting rods, etc) is tired, a top end rebuild may stress the bottom end into failure. It's the chance you take. Also, you may want to inspect the pump, impeller, wear ring etc if you pull the pump to remove the engine . Also, verify the oil injection pump is working. A 20+ year old ski will have issues, that is a given.

guy before me put a new wear ring in it, injection pump seems to be working, ski is definitely getting oil, plugs will tell yah that plus i can see the oil in the lines, I'm hoping to not remove the motor

i bought the ski from a old feller, that used it to putt around in fresh water, so.. not too sure on why it failed.

so it's a 657x FOR SURE?

 

[grss429]

guy before me put a new wear ring in it, injection pump seems to be working, ski is definitely getting oil, plugs will tell yah that plus i can see the oil in the lines, I'm hoping to not remove the motor

i bought the ski from a old feller, that used it to putt around in fresh water, so.. not too sure on why it failed.

so it's a 657x FOR SURE?

Well, took head off and look what i found....


I think this is running lean, the first day i bought it i took it out without rebuilding carbs and it ran like poop... then i took it and rebuilt carbs/fuel lines/two oil lines


so pretty much, I need Pistons
Rings
Gaskets
Circlips
Upper bearings
Wrist Pins
Your cylinders bored to fit.

and a new head

 

[MacAddict]

That sucks man.... sorry to see it.... did the previous owner redo the top end and put the pistons in backwards and the rings snapped off on the exhaust port? That's what happened to me on my gti

 

[grss429]

That sucks man.... sorry to see it.... did the previous owner redo the top end and put the pistons in backwards and the rings snapped off on the exhaust port? That's what happened to me on my gti

from what i can tell the previous owner, didn't do any topend work to it.. he was old.. rode it in freshwater around creeks

 

[mikidymac]

With that much crap bouncing around in there there is a good chance the crank is shot too.

 

[grss429]

With that much crap bouncing around in there there is a good chance the crank is shot too.

it ran, and never knocked so i think it will be opk

 

[mikidymac]

It's a 2 stroke so the crankcase is connected to the combustion chamber by the transfer ports.
With debris in the cylinder like yours it almost always ends up in the crank too. When you pull the cylinders make sure you look down in the cases really good.

 

[grss429]

Will definitely do that, so when looking for parts its for sure a 657x? Is there a number on motor to be sure?

 

[eavega]

Will definitely do that, so when looking for parts its for sure a 657x? Is there a number on motor to be sure?

If its a 95 SPX, then it has the 657x engine. There should be a plate on the mag cover that says what kind of engine.

-E