1999 XP accelerator pump

[JKSTI&R1]

Hey Guys,

Ok, so I took my ski out to the lake the other day for the first time since last Oct and it had a hard time running under 3k rmps. I did clean carbs and change over all the fuel line last Summer. I havent take it out since until the other day. It ran perfectly after it hit over 3k in the water, bogs at low idle and idles a little rough, but got it up to 61 mph that day in choppy water. So I read its prolly my accelerator pump. So tonight I was pulling the carbs back out to check the pump and I noticed that there is a nipple ( lower one towards the motor ) had no hose to it. I looked around and for the life of me I cant find the hose to go to it. It also seems that there is fuel in the lower hull, so im assuming this is my problem. Would it even run with this not connected or is it bogging because it only had 1 carb getting fuel from the pump?

 

[ski-d00]

not sure which nipple you are referring to, maybe post a pic. it could be your return line which is why it is dumping fuel into the hull. if it's small, it could be your supply to your acc pump.

 

[howie099]

If the accel pump is that same as on my 1800 Sportster which I think the setups are you have 2 lines. The intake line from the carb fuel circuit at the bottom of the card to the pump and than the pump back to the carb top. If the line is missing you will leak gas pretty much all the time since the bottom line is the charging line and the top one gives you the squirt when you pull the throttle.

 

[JKSTI&R1]

Hey Guys,

Thanks for trying to help me. So I took the carbs out or started to and I didnt even have the line from the pump to the squirt nozzles hooked up, duh. SO I hooked them up and put it on the hose and it started right up and stayed at 3k rmp's, but now when I give it throttle, it bogs and wants to die. In the water it idles fine, give it gas and it bogs. So I pulled it out of the lake and started it up, idles at 3k perfect and I have to feather it to clime rpms but at any point if I give it a lot of throttle, it just drops the rpm's and will die. Do you think my carbs are bad or do they need to be rebuilt again? I did it begging of last season when I put new fuel lines in. Or is it still my pump? I check the compression and the spark are both fine. Is there something I am missing here..... Anyways as always thank you all for trying to help me and I hope to get this fixed asap......grrrr

 

[howie099]

Did you replace all the rubbers, needle & Seat, & accel pump? The fuel pump usually comes with the rebuild kit.

 

[Coastiejoe]

When you rebuilt them last year, did the ski run properly?

 

[JKSTI&R1]

Hey guys,

I didnt replace the N&S nor did I rebuild the pump. I just cleaned them and put in new parts that looked like they needed. The carbs were super clean and prolly didnt need cleaned at all but I didnt want to chance it. I did put in new gaskets, diaphragm etc... I didnt change the spring or anything. Yes the ski ran fine and here is the crazy thing. I took the ski out 2 days ago, when I was having problems with it not wanting get to rpms and I noticed that I didnt have the accelerator pump line even hooked up but even that day, once I got on it and passed 3k it ran perfect and I even got it up to 61 mph. Ran great for the few hours we were out there, well as long as we kept the rpms up. So when I got home I hooked up the pump lines and ran it on the hose and it seamed to do fine. I had the water box off and it kind of bogged when I gave it a good amount of throttle but It was very little bog and I figured it was just to much air going in because of the box not being hook up. So we went out today on the lake and it started right up, idled perfect on and off the trailer but as soon as I gave it any throttle, it bogged and wanted to die. let off the throttle and stayed running perfect. So now that I hooked up the pump line, now it wont run on throttle when just 2 days ago with the pump line off, it did. How can it change from night to day, just like that. Does the 99' xp have a fuel pump in the tank or is it just a baffle like all the others? I have rebuilt many many carbs on my skis and I just cant figure this one out. I even double checked and re set the carbs to factory specs, which there were already at anyways..... I was thinking about pulling the carbs and re building them again and the pump as well, but isnt the pump just for under 3k rpms and then the carbs kick in, so if it was the pump, wouldnt it not run as perfect as it does at idle on and off the trailer.....

 

[racerxxx]

Just skimming this, where did you get the rebuild kits and what brand are they?

Sent from my SGH-T889 using Tapatalk

 

[JKSTI&R1]

Im not sure what kits I used, It was last season and it did run after that. It seams like it is starving for fuel or too much fuel and flooding. The strange thing also is I dont get any beeps when I plug in the key,now that I think of it, I dont think I ever have.........If it is the Mpem, could I swap it out think my 98' gtx or my 98' gsx, both have the 951 in them....

 

[JKSTI&R1]

Ok update ***

So I just went and started it on the trailer and it started right up and got to the 3k rpm's, if I feather the throttle up pasted like 4k and them gas it more, it revs up great and gets to full rpm's, but if I gas it like 50% and not feather it, it bogs and wants to die...... So does that mean its not getting enough fuel?

 

[JKSTI&R1]

Ok went t my jet ski shop and he said it might be my voltage regulator. So I went and started it up and it read 12.7v not on and when I turned the ski on it never changed. It stayed the same 12.7v. Shouldnt it of jumped in volts when the ski's system kicked in? I think I read somewhere it should be around 14v when the ski is running......

 

[JKSTI&R1]

Anything guys......?

 

[mikidymac]

These are not charging systems like an alternator and are not very strong. They are dependent on RPM to charge more. It idle you will only get about 12.5-13 DC volts and at 4500-5000 rpm only about 13.7-14.5 DC volts. If it doesn't go above 12 volts there is probably an issue. You also need to check for AC voltage because when they go bad they can allow AC voltage to the system and cause all kinds of running issues.

I think the 99 XP might have an internal voltage regulator and you can't change it also I don't think the MPEM can be swapped with the 98'GTX.

To me it still sounds like you are starving for fuel at the upper RPM's.

As far as no "beep beep" the beepers are know to go bad so I wouldn't worry about that till it is running good.

 

[howie099]

It should change in voltage when when you give it gas, but you have a generator not an alternator like cars have. Usually goes in the 13v range. The regulator is in the electrical box. It could be a bad charging stator also. You can do a static test on charging stator to see if it is good. The regulators are easy to swap out. It is sounding like your accel pump is still not working. Also check the feed line for the accel pump it has a small jet in there if you still have the OEM line that could be clogged also. The easy way to test the pump is after you run the ski kill it and pull the throttle and you will hear a squirt of gas go in. Only happens once since that all you get unless it is running. That is what gets you past the bogging when you hammer the ski. I can hear it in my boat when it is off so can probably see in in the ski if you take off the arrestor.

 

[JKSTI&R1]

Hey Guys,

So update. So I got the new stator installed and the ski will start up and idle fin, but as soon as it is given any gas it dies on the trailer in the water though. So off the trailer and in the lake, we can feather it fast 3k rpms and then it runs perfectly. I did adjust the carbs to factory specs but it seams like its not getting fuel before 3k. so should i turn the low end screw out a bit and see what happens?

 

[ski-d00]

Is your acc pump working? Do you see fuel squirting from the nozzles at the top when the throttle is pumped?

Have you checked your compression?

Factory carb settings will work very well if the carbs are clean. Have you checked/cleaned your whole fuel system including the fuel selector switch?

 

[mikidymac]

Don't just adjust the carbs from spec and keep trying to run it. You have a fuel issue and if you keep running it lean you could damage the engine. A stock ski should rum perfectly with stock settings. If not something else is wrong.

 

[JKSTI&R1]

Is your acc pump working? Do you see fuel squirting from the nozzles at the top when the throttle is pumped?

Have you checked your compression?

Factory carb settings will work very well if the carbs are clean. Have you checked/cleaned your whole fuel system including the fuel selector switch?

Ok here is what has been done up to date..... Last year new fuel lines, cleaned and rebuilt carbs ( yes with oem Mikuni kits ) pulled and cleaned fuel selector. All new lines on the carbs, set to factory specs. New battery and now a new stator. It was thought maybe the stator was the problem, but it is still acting up. But on a side note, after pulling the stator, there was a broken wire in the coil, so its good it was replaced. It starts right up and idles fine, forever on the trailer in the water. I do think the idle is down around 1100 in the water, so I can raise that but note sure its that simple..........

Don't just adjust the carbs from spec and keep trying to run it. You have a fuel issue and if you keep running it lean you could damage the engine. A stock ski should rum perfectly with stock settings. If not something else is wrong.

I only ran the ski to try and figure out the problem, not playing with it at all. The compression is 150+ in both cylinders......... I do remember yesterday that when it wanted to die when given throttle, if I pulled the choke for like half a second and let go, it would jump to 3k and run fine, then when we slowed down under 3k it would die. Starts right back up and idles fine. So I have a 98' gtx ltd and Im going to see if the carbs insides are a match, set it to 99' xp setting and see if that fixes the problems. Out of the tons of ski's I have rebuild, only had a few that the carbs were just bad.........

Just curious if anyone knows if the 98' gtx ltd Mpem will work with the 99' xp. Maybe the problems in the Mpem...........

 

[mikidymac]

98 and 99 are different.
My 2001 XP was acting similar and I had just rebuilt them and checked everything. Or so I thought. When I pulled them back off the ACC pump wasn't squirting anything. It took over an hour to finally get the check ball loose and finally it was squirting like a champ. I have not retested it since as we have no water in California.

 

[JKSTI&R1]

Ok, thanks for the heads up. Im going to pull the carbs and check them out again.............. Bahhhhhhhh lol