2003 low power

[Steven Osley]

My girlfriend has a 2003 seedoo with the 717 motor in it. It basically maxes out at 30 mph top. My question is I did a compression test and they came back 118 and 120. I am a mechanic but know very litte about seedoos but I though even though the chambers are close that this was low and maybe causing the low mph. Anyone know what the compression should be because I get mixed answers when talking with people. Also this is a brand new engine with less than 50 hrs on it using premix. Thanks.

 

[Coastiejoe]

A near perfect engine will be 150 psi. A very good engine around 135 psi. An ok engine at 120 psi.
One it starts to drop below 120, that is often a sign that you will be doing a top end over the winter months. At 120 psi I have seen may go all season long and not be an issue. If you get to around 100 psi, it is done....

A new engine often has slightly lower psi and the parts need to mate. As they do, the compression will increase a bit.

I am pretty sure I am correct on the info I gave you. I believe the 951 model is slightly different that the 717.

Is the engine revving up and you just don't go, or does it bog and not rev?

 

[Steven Osley]

It has a little problem getting up on top of the water especially if the water is choppy but once it gets to around 15mph it goes smooth up to around 25 to 30 mph. The motor sounds fine and clean at wot too. Nothing in the impeller either. I took the carb apart looked great and replaced plugs and exhaust gaskets too. I know they should get to around 40 to 45 though.

 

[Coastiejoe]

Does the engine rev up like if you were in a car and floored it but the tires are spinning and you don't really go anywhere.
Or, doe the engine RPMs basically stay low and progressively increase as the speed increases?

 

[CReynoldsMIZ]

118 is too low. Recheck with another tester. Won't run good at those numbers. Who did the rebuild? Warranty?

 

[benjilafouine]

Yes, try another compression tester. Is this a GTI LE? Top speed should be around 42 mph. I also found out with mine that when you are steering strong to the left or to the right and if your motor is weak, it will have issue accelerating. I replaced my engine last year.

Benji.

 

[Steven Osley]

I have tested it with 3 testers all about the same one a snap-on. It just slowly revs up and accelerates slowly until it tops out at around 25 to 30. It does slow down to 15 or so when you turn hard left or right too. This was a brand new motor supposedly.

 

[Coastiejoe]

If it doesn't miss, then you pretty much have to have a fuel related issue I would think...

What was the reason the engine was rebuilt/replaced?

 

[mikidymac]

At 118 with three different gauges that engine is shot. A rebuilt engine with 50 hours should be at 150 psi.

 

[trace864]

Does the engine rev up like if you were in a car and floored it but the tires are spinning and you don't really go anywhere.
Or, doe the engine RPMs basically stay low and progressively increase as the speed increases?

Hi.. I'm the girlfriend, owner of the Sea Doo in question.. Your first question, is about the most accurate description of how this thing is behaving. It's floored and the tires are spinning for sure.. And you don't really go anywhere. It sounds like it should be flying. It spits and sputters up to about 15 mph then clears up but won't get over 30 mph and sometimes not even that. My super sweet boyfriend has been killing himself trying to figure this out. My feelings are really going to be hurt if this is a compression issue bc although the supposed brand new motor was installed late August, 2013, we haven't had much of an opportunity to put more than 10 or so hours on it, so the warranty is done! The break-in process was flawless. I thought I was good to go..

 

[benjilafouine]

As [MENTION=53237]mikidymac[/MENTION] said "At 118 with three different gauges that engine is shot. A rebuilt engine with 50 hours should be at 150 psi", he is right. He proved his point no later that today with my ski.

That being said, if compression is really at 118, your engine may go kind of fast but in the end, it will lack power (30 mph is NOT normal). My same engine will go 42 mph at WOT at 149 PSI.

As for hard turns, they are hard on this engine because my ski is long (3-seater) and with a not a so powerful engine: speed goes down as well on mine so this is not necessarily proof of malfunction. Whatever model of Sea-Doo you own, and at no more than 200 pounds on the ski, a 717 engine 3-seater should go to 42-45 mph on calm water on average.

That being said, and until you test your engine with a $400.00 compression tester, you can never be sure. Trust me. Mikidymac will tell you. I wish your gauges were all of the same brand to ensure a wrong result or else, what you get could be reality (engine fried).

Finally, if the motor is really revving up and with limited speed (such as 30 MPH), you must also consider that the problem may be multiple, meaning both an engine issue and and a jet issue (impeller, wear ring, etc.).

Benji.

 

[Coastiejoe]

Ok. I think you have potentially 3 issues.

1). The high engine rev but not going anywhere. You are experiencing cavitation. In most cases it is the wear ring. Get a camera in there and post a picture for us. The gap from the impede to the wear ring should be no thicker than the width of a dime. It can also be caused by a bad Carbon Seal.

2). The sputtering is either the engine bouncing off the rev limiter or a carb issue. I would not address this until you figure out the cavitation issue.

3). At 118 psi (assuming it doesn't get better once the parts "Mate"), then you have an issue. At 120, that is normally the lowest you can go and still run reasonably well.

 

[mikidymac]

The key as others have indicated is the "clutch slipping" feeling. 99% of the time it is the wear ring in the pump. Easy $40 fix. THen we can move on to the more expensive repairs if it is not a cavitation issue.