1994 Seadoo SPX hard to start in water

[beebs208]

I have a 1994 Seadoo SPX and I am having problems with starting it starting in the water but it starts fine out of the water.

A little back ground to when it started to act up and what I have done to it since.
It was running great and then came into the dock and stopped. Then we wanted to go out and I could not get it started. I packed it up and then cleaned the Carbs and replace the wear ring. Then I could start it on the trailer with the garden hose attached. Then I took it down to the dock and before putting in the water made sure it started. It started and revs the way it should and idles fine. then put it in the water and would not start. then pull it out of the water and it would start. So I started the ski and backed it into the water (still running) and pushed it off the trailer and it ran great. It would idle just fine. I could cut it off and then start it right back up with no problem. But then after riding the ski it was time to put it up. I turned off the ski and went to get the truck and then tried to start the ski and it would not start. Then got it out of the water and could not get it to start. It would almost start but nothing. I don't know if I fouled the plugs and that is the reason I couldn't get the ski running after being out of the water.

Any suggestions will be great. Thanks

 

[alldodge]

Howdy and :welcome:

This sure is a weird one, there is no reason I can think of as to why one way over another. When you go to start it, the engine does crank over every time, just won't start in the water, right?

 

[beebs208]

Yes. When I start it on the trailer it cranks and starts. but when I put it into the water it cranks but doesn't start.

 

[beebs208]

And once its started it runs like a champ. And i can cut it off, while out on the water, and then start it after 30 sec and it does not struggle to start.

 

[alldodge]

My only thought is your carb or fuel pump, maybe flooding or drain back. When its on the trailer is it level or at a tilt? Figure the boat ramp would be tilted some what.

 

[beebs208]

Before I leave my house to go to the lake it is level and starts. then at the boat ramp its tilted. I was thinking it was the carb that was not sealing off the gas. So my thinking was it is flooding. Do you know of any test that would help me know if the carb is performing how it should?

 

[alldodge]

Before I leave my house to go to the lake it is level and starts. then at the boat ramp its tilted. I was thinking it was the carb that was not sealing off the gas. So my thinking was it is flooding. Do you know of any test that would help me know if the carb is performing how it should?

Wonder if you have the gray fuel lines on your ride. According to what I have found looking at different forums the 1990 models have an issue. Here is a good thread to run though to see if it can help. They need a complete fuel run from tank, to selector to carb and back to tank to work correctly. Even one drop of water can cause some issues
http://www.seadooforum.com/showthre...el-Delivery-Problems-low-revs-bogging-surging

 

[Jeff Walkowiak]

This may sound odd but humor me, engines with low or bad compression will start on the trailer easily but not in the water, so before doing anything do a compression check, the engine turns over faster out of the water because the pump is not slowing it down . In the water the pump is causing it to turn slower. If the compression is good and even test your battery and the ground cables from the engine and the positive cable to the starter and to the solenoid, , Move then and see if they feel brittle also check the connections to be sure the contact points are clean. Put a volt meter on the battery when you crank the engine make sure it is staying above 12 volts. If it drops you probably have a bad cell.

 

[beebs208]

I did I a compression test and the front has only 60 and the back has 130. So it looks like I might need to put a new top end in.
If the piston hasn't scared the walls could I just replace the rings? Or should I replace the whole top end? I have not tore down the motor yet.

 

[alldodge]

I did I a compression test and the front has only 60 and the back has 130. So it looks like I might need to put a new top end in.
If the piston hasn't scared the walls could I just replace the rings? Or should I replace the whole top end? I have not tore down the motor yet.

Your going to need to take it apart to see what is needed. You might be able to get by with a partial job, but you always rolling the dice

 

[Jeff Walkowiak]

Ok another mystery solved.
Now what color is the top of the piston, remove the spark plugs and look at the top of both pistons with a flashlight and tell me what color the bad one is.

 

[beebs208]

No Title

Here are a few pictures of the Pistons and the cylinders. With looking at these pictures can you tell what when wrong with the piston rings? and is this salvageable? I am trying to figure out what to do next. Suggestions?

 

[alldodge]

The top of piston is black so it was getting oil, but then the sides and the ring shows scoring so the oil probably stopped. With a chunk out you could also have lost a needle bearing out of the crank and that got sucked up in there. Either way need to take it all down and see if you need a crank

 

[Jeff Walkowiak]

I don't see any signs of water getting in the combustion chamber, the pistons do look dry so I would say either the oil injection is bad or it is premix and someone forgot to add the oil , remember on the rotary valve engines you need the oil in the crank case between the cylinders for the valve driveshaft bearings, and you need to time the rotary valve correctly when you reassemble it. check the end play on the connecting rods to get an idea of wear on the bearings, you can wash the case out and dump it to see if any trash is in the bottom end, each side is separated from the other and the rotary valve compartment is also isolated so if there isn't any trash and the rod bearings feel tight no end play you may be able to replace the pistons to oversize and bore the cylinders be sure they machine shop matches the pistons to the cut, a good shop will mike each new piston and cut the holes to match and mark each piston for the hole they cut. Cast pistons are not as bad as forged pistons and I would strongly suggest avoiding a forged piston unless the shop knows about cutting over for expansion etc.