Trouble Shooting For Weeks ??

[shaunster]

Hello My Seadoo Brothers and Sisters..

Not a very good summer for seadooing :-(

I have a 1999 Sportster 717

On the lake in July my drivers side motor just completey shut down ?

Checked the coils tested it in the the good motor ..carb is good its getting gas ..the
spark was a little weak so I changed the coil in where the Sator is... now I have a stronger
spark,,.

It turns over but won't start..Its getting its Gas and Spark..Could it be that its not getting the proper air ?

Very Frustrating,,


Your Help would be greatly Appreciated !!,

Shaun ,
Nova Scotia

 

[USAF_Pride]

I assume you changed the spark plugs out?

 

[LouDoo]

Just for a starting point check your compression, remove the spark plugs, ground the spark plug wires, turn off fuel, check with throttle open. Ideally you should have around 150psi, but anything above 130 is O.K.

Lou

 

[shaunster]

I have 120 psi and 150 psi is was that way when I bought the boat..That shouldn't stop it from starting ? It ran liked that for 1 and half summers.. ?

And is they are new plugs.. Thers a good Purple Spark ..

 

[shaunster]

Sorry Typing to fast...

I have 120 psi and 150 psi it was that way when I bought the boat..That shouldn't stop it from starting ? It ran liked that for 1 and half summers.. ?

And yes they are new plugs.. There's a good Purple Spark ..

 

[Coastiejoe]

That compression is bad for two reasons,,,

1). 120 PSI is at the VERY bottom of the scale. If everything is PERFECT it can run. But like I said all must be perfect.

2). You are greater than the 10% variance that is acceptable between cylinders.

If you feel that things are good, (spark, fuel, ect) then you need to take a look at timing type issues / components.

In the end, you will need to do engine work as you are on borrowed time.

 

[1800chall_tim]

That compression is bad for two reasons,,,

1). 120 PSI us at the VERY bottom of the scale. If everything is PERFECT it can run. But like I said all must be perfect.

2). You are greater than the 10% variance that is acceptable between cylinders.

If you fell that things are good, (spark, fuel, ect) then you need to take a look at timing type issues / components.

In the end, you will need to do engine work as you are on borrowed time.

just what you wanted to hear, at least its october not June !!!

 

[LouDoo]

Yep, with compression that low and that different it's time for a rebuild, if it was mine I wouldn't run it again.

Lou

 

[racerxxx]

A 717..... I'm placing bets on a stripped rotary valve shaft gear cause the drive gear on the crank walked. Pop the Rotary valve cover off and give her a look see. Please read the manual before you go digging in if this is uncharted territory for you. Regardless, it sounds like it's time for a rebuild anyway.

 

[shaunster]

A 717..... I'm placing bets on a stripped rotary valve shaft gear cause the drive gear on the crank walked. Pop the Rotary valve cover off and give her a look see. Please read the manual before you go digging in if this is uncharted territory for you. Regardless, it sounds like it's time for a rebuild anyway.

I think the timing is off.. at this point..Its blowing oil and gas out of the carb instead of sucking air..

Your thoughts?

Thanks!!