2000XP Running Terrible

[4Run4Fun]

Ok,
We're dealing with a 2000XP 951 here.
I have replaced the grey fuel lines with brand new automotive fuel hose. I have totally rebuilt both carbs with kits from SBT including the in-carb filters, all o-rings, diaphrams, etc., cleaned the fuel selector switch, and the spin on fuel filter. I also replaced a busted exhaust hose. Plugs seem OK and compression is good. Drained the fuel tank and refilled with fresh 93 octane.
The boat runs like crap. Its VERY difficult to start in the water and almost any touch of the throttle will cause it to stall. In the rare event that you can get it past idle, it will never come close to planing off and maxes out around 2900RPM. There are occasional backfires (through the carb I can only assume) and some of them are severe.
I know this model has reed valves instead of a rotary valve, so I cannot see a possible timing issue.
The whole purpose of replacing all the fuel lines and rebuilding the carbs was to correct these exact symptoms, yet there is absolutely no difference in performance since the job was completed.
Diagnosing this problem seems to be exceeding my mechaincal abilities, so any help from the experts would be great!
Thanks,
Ryan

 

[timmyboy76]

Ryan...did you replace the n/s springs, with ones from the kit?

 

[4Run4Fun]

Yes, the kit supplied several springs and I had to do the best I could at matching. To be honest, I could find very little difference in the springs, and even less difference between the new one I put in and the old one I took out, it looked to be in pristine shape.

I have done this procedure on other skis (all older 580s and 650s) and the symptoms were instantly cured. Beyond the fact that I cannot get any power output, the backfiring really concerns me. Is it a symptom of a larger issue?

Thanks,
Ryan

 

[timmyboy76]

put the stockers back in. those springs look the same, but the weighted "gram" are completely different, thus...chang'n the pop-off in ur carbs...

Your "first" symptom was all clogged up carbs, so you fixed it, then along with that, "re-tweeked" the system, messing w/ the n/s assy.

 

[4Run4Fun]

Great, I'll try that tonight - provided it doesn't rain.

What would be your next guess if returning the needle/seat springs to original fails to improve the situation.

I only ask so that once I take these things apart again, I can check any additional things while in there. I don't own any high-dollar specialty tools, so I am taking these off and putting them back on with reguar allen wrenches, lol. I'd like to do the work as few times a possible.

Ryan

 

[Moto-Madness]

Check the sync on the carbs to.

 

[4Run4Fun]

Not to showcase my ignorance, but you may have to elaborate a little on that. Do you mean check to see that they are opening simultaneously (linkage)?

 

[4Run4Fun]

After reading through some other posts, I took notice of several mentions of lsa and hsa. Where are these adjustments located on the carb and are they labelled? Where should they be set for a 2000XP 951?

Thanks,
Ryan

 

[Moto-Madness]

Those are you high and low speed adjustments. The HSA is a small black adjustment screw located towards the top of the carb and the LSA usually has like a T-Bar on it and is located towards the base of the carb on the opposite side of the HSA.

HSA = Zero Turns
LSA = 1.5 Turns Out + or - .25 Turns

Pop Off should be between 19-22 PSI

Turning the LSA out enriches it and turning it in leans it out.

 

[4Run4Fun]

Great! Thanks for the info!

Just to clarify - by saying 'zero turns' you mean the high spped adjustment screw should be gently bottomed out and left there, and the low speed adjustment screw should be gently bottomed out and then backed out approximately 1.5 turns. Is that correct?

Thanks,

Ryan

 

[Moto-Madness]

That is correct. :cheers:

 

[4Run4Fun]

Tore down the carbs again and replaced the n/s spring with the original. Pop-off tested 22. Re-cleaned everything again - for the heck of it. Put it all back together, but its dark outside so I can't test until tomorrow.

By the way (stupid mistake alert), everyone remember to turn off your fuel selector switch before disconnecting your fuel lines and removing your carbs. When the time came to put the carbs back in - I was greeted with a hull full of 6 gallons of 93 octane. Had to siphon it out with an aquarium hose. I suppose now I'll have to flush out the hull with water before restarting to keep from blowing myself up.

Yes, I am happy to accept this week's Darwin award!

Ryan

 

[4Run4Fun]

2000XP still crappy

Well,
Back to the drawing board. If you recall I replaced the n/s springs from the kit with the old ones that were in the carb prior to the rebuild. Pop-off tested 22.
Still having the same problem. It does start easier now, and the backfiring seems to have ceased, but it still will not pass 3000RPMs in the water. Even on the trailer, it seems to rev up relatively slowly when the throttle is feathered. In other Seadoos I own, if you rev the engine out of water, it absolutely flys up the RPM range.
Guys, what am I missing here? Its as if the engine is in slow motion. It runs, and really seems to idle smoothly on the trailer, and even at an acceptable level in the water - but when you punch it, theres just no go.
It reminds me of my truck when the distributor advance quit.

I am desperate for a solution,
Ryan

 

[mat1112]

i had the same promblem it wont pass over 3000 rpm what i did was change the wear ring and clean my mainjets in the carb i took it to test on the ocean and it runs good not perfect but does pass the 3000 rpm mine is just slow from start then it pops in midrange prrety wierd but fixed tht promblem