how to adjust 96 SP carburetore

[buxidoo]

HI,I just rebuilt the carb and get a mechanic to set it up ,now it does'nt go that fast as before,only when i have a jump with jet ski on the water ,as it get back to the water its a bit faster but after a few second goes back to same low speed ,he also adjust the impeller at the same time ,i don't know is it with the carb or impeller?
THANKS

 

[timmyboy76]

double-check the lsa/hsa, low speed is 1-1/4, high speed is 0...

 

[buxidoo]

thanks for response ,timmyboy

i tight the adjust screw which means 0 and open the idle to 1-1/4,its still the same ,iv got no much speed on flat water but as i get to the rough water it goes to high and fast speed as before i rebuilt the carburetor,
sorry guys English is not my first language i hope you understand my pour English

 

[seadoosnipe]

Impeller......

There is no adjustment for the impeller. What did he do to the impeller? You have the 587 engine, with one carb so it can't be that hard to fix.

How does it idle? What color are your fuel lines? Did you check the fuel filter for trash?

You said he rebuilt it. Did he rebuild it or clean it up? If it was rebuilt, the kit comes with 3 different size springs for the lever. Did you use the correct spring for the right carb?

 

[buxidoo]

impller and carburetor

i dont know what he did for impeller i drop the pump and pick up later ,i rebuilt the carb my self ,i used the same color spring from new pack which was goldenish i didnt used the silver one and all i did pull the spring and made that about to 3mm longer to make it as same length as the old one, i hope it doesnt create any problem, then i had problem with full throttle so get a jet ski workshop to adjust the carb,iv got silver fuel line ,i think the line could be fine because this issue just started after i rebuild the carb,yes i checked the filter as well, there was some water in there,what do you mean by(How does it idle).
why its faster on rough water and slower on flat and surface water?do you think what i just did for adjustment is fine ?
thanks

 

[timmyboy76]

that spring you installed, is one if not "thee" source of problem, stud. The spring you want to install is 80gm-95gm weighted, one you installed is 115gm, which means, your n/s(needle and seat) assy, is not pop'n to allow fuel to flow. Those springs are made for specific applications, thats why theres 4 to a pack...:cheers:dont want to alter those/any spring...
By chance, you still have the factory spring, install it, if not, you want to install the "dull silver" spring. That should put you in ballpark psi...

 

[timmyboy76]

hey stud...also, check the "float-arm"(tang-arm that rides on top of spring), make sure its level with carb body....:cheers:

 

[buxidoo]

still the same

hi timmyboy ,
i changed the spring , the float arm was also level , she still the same ,going heavily,i might need to check the pop up on the carb ,
and any idea why she goes faster after taking off (jump)a few times on the water?
i dont know why did i touch the carb ,it wasnt necessary:banghead:
any way its still fun i like to rebuilt the stuff,and see whats in there.

 

[12nvy]

Your Fuel pump could be leaking aswell did you pump it up and check for leaks? Silly question but how old is the fuel and spark plugs?

 

[buxidoo]

i dont know where is the sp fuel pump,but there is no smell of petrol in the hull ,i got new spark plugs and fill the tank a few days ago,
and if the problem is with the fuel any idea why its ok on the rough water and as it gets to the calm water the speed drops and looks like the jet ski carrying a heavy loud?
i also check the Clearance in between wear ring and impeller blade and thats good, its about 1.0mm, i m thinking to check the pop up on the carb ,it might be the reason?

 

[timmyboy76]

bummer...

hey bux...you replaced the n/s (needle and seat) assy, if not, possible the needle is bad/or o-ring around the seat, needs replaced, and/also, wouldn't be bad idea to do leakdown test on carb/s...

 

[EvilVtec]

:agree:

Leak down will help in troubleshooting. You could have a check valve that is not sealing on pressure pulse, or a diaphram that is leaking slightly and not building pressure at high frequency pulse. The fuel pump is a diaphram pump on the side of the carb. It pumps fuel by passing fuel through a check valve with an oscilating diaphram pump, which is sourced pulsed pressure by the crankcase. If you are unfamiliar with the operation of a diaphram Mikuni carb, check out some online drawings and get acquainted with how it works. This will also assist in your diagnosing the problem. Good luck.

 

[buxidoo]

Thanks guys
i going to check the diaphragm for leaking,but before do that i thought better to ask about this .
what about if i dont have a good idle ,(in the water) could it be the reason? ,because i need to hold the throttle fully and push the start button for 5- 8 sec and when its running also i need to hold it about 1/8 throttle other wise i need to start it again.

 

[seadoosnipe]

Throttle stop screw....

When you get the carb running right or if it's a pain because you can't keep it idling while working on it, look at the cam linkage on the carb. You'll see a small thumb screw with a spring on it that engages a small piece of metal that contacts that scew. This is your idle stop screw. Turn it in just a tad (close) to make it idle up a bit.

If your idle is really rough, you might open your low speed jet screws just a bit. What you do on one carb, do on the other.

Before you make an adjustment on the low speed screws, close the one on your MAG carb. Watch how many turns it takes to seat the needle. Don't turn it tight, just up to the point it won't freely turn anymore. It should be anywhere from one to two full turns open. Then, open it back up about 1 and a half turns. Do the same procedure to the PTO carb. If you find one of them open about 2 and 1/2 turns and the other 2 or less, this could be a reason for poor performance at idle. Both of these low speed screws need to be set the same.:cheers:

 

[buxidoo]

checkig the pop-off

i just check the pop-off a few times its about 21-22, which is the minimum ,iv got only two spring in the pack silver and golden and looks like the silver one is giving me more pressure( 21-22),
and another question what happen if i install one of the check valve (fuel pump disc)up side down?

 

[timmyboy76]

hey bux....
was it a rebuild kit you got, and if so, just those 2 springs., In the pack, you changed/saw the clear/whitish flap valve, or remember seeing one? For the valve, not sure if they can be installed wrong, but believe can be installed on "wrong" side of carb/s. Those are a pain to remove/install, I ripped the bullet plugs hold'n them in...

 

[buxidoo]

yea ,in the carb kit there was only two spring for lever ,as i remember from some threads should be about 4 spring in the carb kit (not sure),any way iv install the silver one,and about those clear valve with rubber in the middle i think one of them installed up side down there is a blue line marked at one side of them which should be up,but it was to late i was already replaced one and its a bit mission to take it off ,might ripped the rubber or damaged the valve