2000 gtx di fluctuating voltage and misfire.

[neo297]

Hello all, new to this forum but have been lurking for a while. I work on my own motorcycles and cars and can turn a wrench but have the benefit of proper tools and obd2 readers. I'm new'ish to pwc. This is regarding a 2000 gtx di 951. I put in new plugs and battery and rebuilt the jet pump, new impeller and ring last year and it ran great all season (fresh water lake in East Texas). It was winterized and battery on trickle charger. With first start up this year it was misfiring blowing white smoke and no power. The fuel was replaced fresh non ethanol gas prior to start up. RED warning light on dash and maintenance warning. NO low voltage warning. I pulled plugs and they were wet cleaned and re gapped to .043 no change. I put voltmeter across battery 12.8 v not running and it was fluctuating from 1 volt to high 12's to 4 to 3 to 8 to 2 to 10 never holding steady voltage while running never above 13.0, only saw that once or twice. Occasionally backfired and would eventually stall. I was hearing clicking coming from rave valve solenoid but not sure if was only at time engine was turned off/stalled. With such low voltage fluctuations maybe that was making it think it was turned off ?? After reading about the rectifier issues being common I bought a " seadoo 2000-2003 951 gtx di heavy duty voltage regulator/rectifier" from RegulatorRectifier.com. I put it in and the problem is still there. Ohms across all pairs of the three yellow stator wires at the regulator are all 0.00, there is no resistance from connector at voltage regulator to connector at rear of coil box at back of ski. With red black connector exiting regulator with engine running reads steady 4 volts should be 14.5? Old regulator was 0-4V. Now I'm confused if regulator is bad shouldn't high voltage at battery be found? Although no seeming resistance at 3 yellow wires in to regulator might stator be bad or did I get a shit regulator out of the box. I also have a 951 rx carb ski that runs great after i redid the jet drive replaced all fuel lines filters and rebuilt the carbs last year. It has steady 13+ voltage at battery while running. Does it have a regulator that I can use to test on the di or is it different. Any help is greatly appreciated. I have downloaded the service manual and have read the relevant sections but am still confused as to what step I should take next. It always beeps twice and starts with placement of key on post. All fuses on mpem all good, I assume 30amp in rear electric box ok as it will start and run.

 

[POPPS]

The DI's are picky about their voltage for the electric fuel pump..if you are charging 14+ plus volts, then it is not a battery/stator/reg charging problem...Make sure you load test the battery to easily remove it from your equation,,,now its time to test the fuel pressure,,,when these pumps go,,,due to having metallic internals,,,rust actually forms,,,and the pump draws extra current,,,so,,,you may be low on fuel pressure,,and also putting excessive load at the battery.

 

[neo297]

The DI's are picky about their voltage for the electric fuel pump..if you are charging 14+ plus volts, then it is not a battery/stator/reg charging problem...Make sure you load test the battery to easily remove it from your equation,,,now its time to test the fuel pressure,,,when these pumps go,,,due to having metallic internals,,,rust actually forms,,,and the pump draws extra current,,,so,,,you may be low on fuel pressure,,and also putting excessive load at the battery.

Thanks popps, I'm not getting 14v charging. The voltage at the battery when running fluctuates between 1 volt to 12 volts never holding steady at any voltage. My meter jumps all over. I never see 14 v at battery with ski running. I put my voltmeter on the two pin red / black output plug from voltage regulator, it is new, I only get 4 volts when ski is running. Battery is new last season and trickled charged on battery tender over the winter. Would fuel pump draw keep voltage from reading steady at the battery or so low from voltage regulator I thought it's out put should be at 14v. I planned on pulling fuel pump to check filters at some point. I can take the battery to AutoZone to have it checked or I may swap out the battery from the rx.

 

[Ckrawiec]

Thanks popps, I'm not getting 14v charging. The voltage at the battery when running fluctuates between 1 volt to 12 volts never holding steady at any voltage. My meter jumps all over. I never see 14 v at battery with ski running. I put my voltmeter on the two pin red / black output plug from voltage regulator, it is new, I only get 4 volts when ski is running. Battery is new last season and trickled charged on battery tender over the winter. Would fuel pump draw keep voltage from reading steady at the battery or so low from voltage regulator I thought it's out put should be at 14v. I planned on pulling fuel pump to check filters at some point. I can take the battery to AutoZone to have it checked or I may swap out the battery from the rx.

The classic problem....the rectifier/regulator is kaput.....if you are getting bouncing voltage at the battery with a running ski.....it should be a fairly smooth 14VDC (in that neighborhood) with a functioning rect/reg. The ski is making electricity, but it's all over the place because the rectifier/regulator is malfunctioning....sounds like your problem to me anyway!

 

[neo297]

Thanks for replying. That was my first thought but with the brand new regulator it does the same thing. I am not sure if a failing fuel pump could cause such fluctuations and with the 2 pin connector from the regulator showing only 4 volts while running I'm not sure if stator could be part of the problem. Is there a way to check the voltage output of the stator other than just resistance at the three yellow wires into the regulator.

 

[etemplet]

I wonder if the fuel pump is going kaput and drawing excessive amperage. Battery voltage should not jump around. Are you sure your meter is working correctly?

 

[neo297]

I have another ski , RX CARB, and using same meter it was holding steady 13+ volts at idle across battery terminals I had checked just to be sure that one, the meter is ok and two that the voltage wasn't supposed to fluctuate when the engine was running fine the carb ski runs great. I think though the carb ski has an internal regulator so I can't just swap it out to the di.

 

[Ckrawiec]

I'm a bit confused...but when is that ever not the case....

I'm looking at the 2000 model year wiring diagrams:

the 2000GTX has an integrated voltage regulator in the MPEM (according to the diagram)....so, you don't have that situation since you stated you have an external regulator.

the 2000GTX RFI has an external regulator, so that must be the diagram I need to look at then.....all you really care about is the voltage on the RED wire coming out of the regulator....that should be 14VDC (+/-) steady, feeding that voltage back to the solenoid post connected to the + side of the battery. If that voltage is bouncing all over the place...the regulator could be bad (I've personally experienced 2 bad regulators right out of the box). The other possibility is your ground path for the regulator could be suspect as well, so triple check all your connections - clean, bright and tight. You can check the resistance on the 3 yellow wires into the regulator to get a health check on the magneto- mark the wires 1,2,3 and check resistance between 1-2, 1-3, 2-3....should be .6 ohms thereabouts and be equal on the 3 legs (within .1 ohm).....that could indicate if the magneto is OK.....otherwise, you could have a magneto issue throwing strange AC voltage into the regulator.

 

[WaarrEagle]

Even if the regulator is bad, it seems odd that he would see such low voltages across the battery when running. With a charged and functioning battery, it should not drop so low, right? I would swap batteries with the RX and try again.

 

[POPPS]

If you have an external regulator,,,then disconnect the yellow coupler,,,then eith your meter on AC volts,,,which is the unregulated voltage,,,start it up,,,and you should see 25 plus volts from all three pairings of yellow wires,,,mark them 1st 1,2,3,...then measure 1/2,,1/3,,,2/3.,,it is possible to have the yellow wires pass the stationary non dynamic resistance tests,,,but under load a wire can short,,,I never put all of my faith in the non dynamic tests,,,also check for short to ground with each yellow wire,,.failing the resistance tests saves you the hassle of doing the dynamic AC voltage charging test,

 

[neo297]

I'm a bit confused...but when is that ever not the case....

I'm looking at the 2000 model year wiring diagrams:

the 2000GTX has an integrated voltage regulator in the MPEM (according to the diagram)....so, you don't have that situation since you stated you have an external regulator.

the 2000GTX RFI has an external regulator, so that must be the diagram I need to look at then.....all you really care about is the voltage on the RED wire coming out of the regulator....that should be 14VDC (+/-) steady, feeding that voltage back to the solenoid post connected to the + side of the battery. If that voltage is bouncing all over the place...the regulator could be bad (I've personally experienced 2 bad regulators right out of the box). The other possibility is your ground path for the regulator could be suspect as well, so triple check all your connections - clean, bright and tight. You can check the resistance on the 3 yellow wires into the regulator to get a health check on the magneto- mark the wires 1,2,3 and check resistance between 1-2, 1-3, 2-3....should be .6 ohms thereabouts and be equal on the 3 legs (within .1 ohm).....that could indicate if the magneto is OK.....otherwise, you could have a magneto issue throwing strange AC voltage into the regulator.

Thanks guys for responding The problem one is the gtx DI, not gtx or gtx rfi. I was confused as service manual is divided first part doesn't list rx, rx di or gtx di its halfway through scrolling down I find a separate manual for those 3. At first i was at the lake with the other ski when first starting to troubleshoot. When I saw the voltage jumping around but below charging voltage I just started the other ski (rx) and checked the voltage across it's battery normal and steady. I didn't see an external regulator to swap at that moment. Got the gtx di home ohms across the 3 yellow wires from stator all pairs exactly 0.6 ohms, rechecked today same. Assumed it was voltage regulator bought new no change in volts at battery or how it runs, continuity good to rear box plug. Red wire out of new regulator only shows 4 volts. Retrieved battery from RX looked again and on wiring diagram no external regulator on rx. Am charging Rx battery now pulled original battery out of di. Tomorrow will put Rx battery in and see what happens. Hate to buy another new VR without knowing for sure it's the issue and sure as hell don't want to have to swap stators. I just feel this is electrical not draw from fuel pump failing although i do need to change filters.

 

[neo297]

If you have an external regulator,,,then disconnect the yellow coupler,,,then eith your meter on AC volts,,,which is the unregulated voltage,,,start it up,,,and you should see 25 plus volts from all three pairings of yellow wires,,,mark them 1st 1,2,3,...then measure 1/2,,1/3,,,2/3.,,it is possible to have the yellow wires pass the stationary non dynamic resistance tests,,,but under load a wire can short,,,I never put all of my faith in the non dynamic tests,,,also check for short to ground with each yellow wire,,.failing the resistance tests saves you the hassle of doing the dynamic AC voltage charging test,

Awesome that's what I was looking for wasn't sure how to voltage check stator will definitely be doing this tomorrow.

 

[etemplet]

ON the 2003 RXDI I had the Regulator was up front behind the MPEM.

 

[neo297]

I know this is a work in progress and I thank everyone who has responded to this point I will post my results when done.
cc

ON the 2003 RXDI I had the Regulator was up front behind the MPEM.

I did not see one or any wires from the harness going behind mpem on the Rx I'll get out to the lake and recheck though.

 

[neo297]

Further f/u with the battery from the Rx in while running it was holding steady 12.3 volts at idle no change with rpm increase. I have 0.6 ohms across the 3 pairs of yellow stator wires and 19.6 to 20.5 v at idle even across all 3 pairs and increases to 55 to 60v as I rev it I'm in the front so I can't see exact rpms. Still 4 volts DC out of red wire from the new regulator. No continuity to ground from any of the 3 stator wires.

 

[neo297]

If I assume my stator is good then I have to say my new voltage regulator is bad out of the box. I got a new multi meter to be sure my readings were accurate. Now when I check it seems ski is just running off battery as it has steady voltage but only 12.3 V. across battery terminals. Where should I go to get one I don't want to just randomly pick internet sources. I just want to see good out put from regulator and charging system then see if the misfire / ruff running is still present. The ski is a 2000 but only has 57 hours on it. I checked compression for shits and giggles while I was cleaning rave valves today it had 135 on front cylinder and 140 on rear. I feel like it has more life in it but want to be systematic about working through its' current issues.

 

[WaarrEagle]

I would buy it from OSD: OSD Heavy Duty Rectifier - Sea Doo 787 RFI / 947 DI (1998-2004) [OSD4001] - $97.99

 

[neo297]

I'll update after getting new regulator #2

 

[neo297]

Well osd out of stock will wait to see when they are back in