Help!! 99 XP won't start.

[dimesismoneytoo]

Okay guys, I go out today everything is running perfectly. Then, my doo just bogs down and will only do 4000 RPMs at WOT. Then it sputters and dies. I couldn't get it to start after it died. So luckily someone stopped and asked if I needed help and towed me back to the ramp. (about 4 miles) I checked the water separator and there was fuel there, and I just had the carbs and fuel system completely replaced. So what could it be. But first, how do I check to see if the motor is flooded with water from the tow. And how do I remove it so I don't hydrolock m motor. We only did 5 MPH set on cruise. So should it be really bad?

 

[jhjesse]

Pull the plug wires and place on the grounding posts. Remove the plugs and put a rag over the plug holes while cranking the engine over. If there is water in the engine it will shoot out the plug holes. On the chance there is water in the engine keep cranking the engine at 10 to 15 second intervals, as to not overheat your starter, until the water is out. Get some fogging oil and spray into the cylinders and crank the engine. Do this several times to displace the water. Put the plugs back in and try to get the engine to crank. If you can get it to crank and run for about a minute and you will have gotten all the water out.

If you were towed at 5mph or less I would say there is probably not any water in the engine.

 

[rvaughn704]

Pull the plug wires and place on the grounding posts. Remove the plugs and put a rag over the plug holes while cranking the engine over. If there is water in the engine it will shoot out the plug holes. On the chance there is water in the engine keep cranking the engine at 10 to 15 second intervals, as to not overheat your starter, until the water is out. Get some fogging oil and spray into the cylinders and crank the engine. Do this several times to displace the water. Put the plugs back in and try to get the engine to crank. If you can get it to crank and run for about a minute and you will have gotten all the water out.

If you were towed at 5mph or less I would say there is probably not any water in the engine.

I agree with Jesse on this.

Now for your original issue.
Let get the compression checked on that engine. That will tells us where to start. No need to chase a fuel delivery issue if you have lost compression which is very possible and will have the symptons you describe.

 

[ueww40]

My question is of a different note and I appologize if I appear ignorant to something that everybody else may be aware of, but why would the engine flood with water when you tow the sea doo at any speed above 5 mph.?

 

[dimesismoneytoo]

Pressure builds up and backs water up the exhaust, flooding the cylinders.


Sent from my iPhone using Tapatalk

 

[ueww40]

Ok, never thought of it that way. Sounds sensible though, even though I never heard this before nor is it written as a warning in my manual. But what strikes me as weird is that you knew that, but did not have a clue how to get the water out of the cylinders. Taking the plugs out to avoid waterlock and cranking it would be my first instinct and I know nothing. Can someone else out there second this back pressure theory please.

 

[Bnelson]

Second, third and fourth that.... If you tow it, clamp off the water inlet line or you will fill the motor with water, same principle as if the ski was running, being towed there is still water circulating through the pump, thus cooling..... You have to tow it fairly fast though to create the same pressure

 

[ueww40]

Thanks, Bnelson. I learned something. Manual only says: Tow at moderate speed. I read that as a safety on the water thing rather than an intrusive mechanical warning. Your post is clear and makes perfect sense now.

 

[Bnelson]

No prob at all man.... The manual is definitely not clear as to why to tow at moderate speed. I would think they would want people to know that

And yes to the OP, a compression check would be good to know first.... Also, no if you towed back at a slow speed you should be fine... But if there is any doubt in your mind you need to get that ski running ASAP!

 

[dimesismoneytoo]

Okay, no water in the motor. GOOD! Compression is 125 in the front hole, and 130 in the back one. I've been told that those numbers are good for a 951. Motor only has 20 hours on it, could it rell lose compression that fast?

 

[Bnelson]

Well anything can happen.... But, your compression #s are just fine.... How about the fuel lines? Are they still the factory grey lines? Carbs ever been rebuilt?

 

[dimesismoneytoo]

Carbs just rebuilt, all new fuel lines


Sent from my iPhone using Tapatalk

 

[Bnelson]

Sorry missed that in the first post, is the first run after all that work has been done? If not could be a possible rectifier issue... Will it start now after it has been sitting?

 

[dimesismoneytoo]

No I've ran it about 6 hours since the fuel system work. I haven't tried to start it since I got it home the other day


Sent from my iPhone using Tapatalk

 

[Bnelson]

Ok, see if it starts today.... That will help to point us in the right direction.... Check and see if you have spark while your out there.

Also, how much fuel is left in your tank?

 

[dimesismoneytoo]

Okay, runs on the trailer. Nice clean plugs, good spark. Runs really rough though. Like it starving for fuel or air.


Sent from my iPhone using Tapatalk

 

[dimesismoneytoo]

And I have around 3/4 full tank.


Sent from my iPhone using Tapatalk

 

[Bnelson]

Ok that helps, in the grey e-box you will find the rectifier. It will have 3 yellow wires and one red wire coming off of it... Unhook the red wire and see if it clears up the roughness

 

[dimesismoneytoo]

Where is this grey ebox you speak of?


Sent from my iPhone using Tapatalk

 

[Bnelson]

Hmm not sure on the 99, thought it was towards the front of the ski... But I've been wrong before, maybe someone will chime in and let us know where the rectifier is, don't think yours is integral to the MPEM on that model

Possibly in the black e-box

 

[dimesismoneytoo]

Everything I've read says it is integral to the MPEM on the 99 XP. And I've also read to check the RAVEs before jumping to replacing the MPEM. How do I go about doing this? First jet ski, gotta start somewhere.

 

[- BiRkS_]

Check the raves first yes. make sure they are closed fully. Unfortunately to test the internal regulator you must disconnect the 3 yellow wires from the stator plug OR at the MPEM. I now own a pin tool, but my last ski i cut the wires. My regulator was indeed bad, it was overcharging the system and limiting rpm to 4-5k rpm. You must test with a voltmeter on the battery. Must be above 12.5 volts while running, preferably 13-14.5 volts at 3000 rpm. Mine was 15+ volts when the ski would limit rpm. Then you have to test the stator as well. should be 20-30 volts AC between either 3 wires when running and show no resistance to ground with either connection. I found one of my yellow wires to the MPEM was shorting to ground, indicating an internal regulator issue.

If the regulator is bad, you can buy the external regulator kit, or do what i did on my last gtx... cut the 3 yellow wires at the MPEM and splice them into an external regulator from a 787. Then red power wire with inline 10A fuse and a ground is needed either right to battery or constant power/ground in the e-box.

 

[dimesismoneytoo]

How do I go about checking the raves/ cleaning them. I don't even know where to begin with this motor.

 

[dimesismoneytoo]

I downloaded the service manual for this ski, and it doesn't have anything about the 951 engine in it. So help would be very much appreciated.

 

[- BiRkS_]

The RAVES are under the 2 black/red caps ontop of the engine. To remove them, unclip the retainer and hold the cap in place, there is a spring underneath. Take the retainer off and the cap and spring slowly and set aside. cut the tie strap off the hose at T connection, or at the rave solonoid and pull off the hose. Loosen the 2 5mm cap screws on each rave and remove the it by pulling up. I like to mark which valve came from each cylinder.

Take over to a bench to disassemble. Hold the spade like valve and use a 10mm wrench to loosen the black cap and spin the valve out. I find it easier to rotate the valve rather than the black cap as its attached to the bellows (rubber boot).

Once valve is removed, inspect the O-ring on the shaft. If it is hard and brittle, replace it. If its still perfect then keep it in a safe place. Soak the valves in carb cleaner for a couple hours and most of the carbon should come off. Then a wire brush or a cookie disk on a die grinder will polish them up to look like new. Inspect the bellows for any rips or tears. Wipe up any residual oil and gunk. Avoid carb cleaner on rubber bellows. To clean the bores in the cylinders, rotate engine so piston is covering the hole. Use a rag wrapped around a blunt screw driver or rod soaked with carb cleaner and clean the bore. Use a clean rag to soak up any reidual cleaner and dirt. I use compressed air too to make sure its all clean. Then take a tablespoon of oil and poor into each bore. Re-install and you should be good to go.