96 GTX mid range bogging HELP please !

[reelimpatient]

I had some bogging in the low end RPM range between 2000-3000 RPMS. I decided to pull the carbs and clean and inspect them for trash and worn diaphrams. I cleaned them and put them back on and adjusted them per Mikuni's factory settings and still have low end bogging. It does scream above 4000 rpms and now runs up to 6000 rpms whereas before it would only turn 5500.

It has new plugs, runs premix and compression is @ 175 per cylinder.
All filters are clean and have been checked.

After that, I ordered a carb rebuild kit and
Totally rebuilt carbs, replaced main jets and needles, springs, orings, check valves, rubber gaskets etc. Was real careful about it being clean and putting it back together correctly.

Replaced gray fuel lines with new.

Spent an hour or two on lake Saturday trying to dial it in, and now boggs badly at 3000-4000 rpms.
0-3000 rpms seems to run fine, beyond that, it will bog and die if I try to accelerate. I can sometimes feather the throttle and get it to jump past the bog to 4000 rpms and it will then take off like a rocket, and runs strong up to 6700 WOT.
What the heck can this be? This is driving me crazy and I want it fixed.
Runs premix and has great compression. Come on Pro's I know you guys have seen this before.

Thanks for any help !

 

[Bills86e]

Whats the compression? Have you cleaned the Raves?

 

[reelimpatient]

The compression is 175 on both cylinders. I cleaned the rear rave because I found that it was not able to do the full travel of open and closed. I have not cleaned the front. But the front Rave does travel fully open and closed.

Could that be the issue even though it freely travels the full length?

Thanks !

 

[Bills86e]

At around 4400 rpm is when the power valves should open and you will feel the surge
If you had any earlier water injestation, I would advise checking the crank index. (180*
apart TDC-TDC). Do you have the paint on carbs & selector chipped? Aluminum Oxide
can turn gas/petroleum product to a steel-like clog in the carb passages. Mikuni
states this fact, and adises painting the carbs for that reason. Do a plug chop and
compare the plugs with the plug color chart listed in Seadoosnipes corner on 787
carbs. You can drill the three fuel selector valve tubes with a 3/16" drill to see an
example of the steel-like crud on the drill's flutes. Then you'll know what to look for
when in the carb(s). Hope ya got some small wire size bits. Do a leak-down test after you re-assemble the carbs, keeping pop-off within 1 psi of each
carb, and syncronize the butterfly's.

 

[reelimpatient]

Not sure what you mean about the crank index. The carbs are missing paint, but they have just been rebuilt and cleaned pretty well. All passages were checked to be open, including tiny jets.

How does the fuel selector switch come off? I tried to take it off , removed screw on the rotating knob, but I couldn't get it to come off? Does the outer housing screw off?

Crazy thought, but could I back the ski into the water still on the trailer and bring it into the bog range and try adjusting the low rpm bottom carb screws and see if I can adjust it gradually until I hit get it to run right in that rpm range?

Also, someone said something about the rectifier, how would that affect it in that rpm range? And wouldn't that not change based on carb settings?

Thanks for the help! I really appreciate it

 

[Bills86e]

under the cap on the knob is a phillips #2 screw, take it out and pull cap with a pair
of pliers where you normally grab knob. Under knob is a nut, take that off, hammer tap the valve into the hull.

Yes, you could back it in, tied to trailor.

Rectifier changes the A/C current produced by Stator/flywheel into DC current. That
is used by the multiple electrical products module & battery. When its internal diodes
burn out, AC goes into MPEM as electrical Havoc! Ski would run & sputter dramatically.

 

[reelimpatient]

Ok, now I am getting somewhere.
1. If the ski runs WOT without any issues, is there likely a fuel delivery issue at throttle up and need to check the fuel supply valve for crud?

2. If it runs fine at all rpms except 3000-4000, could it really be the rectifier?
If so, I thought I saw where you could disconnect one lead from the rectifier and if the ski ran fine, that was your problem, if that is so, what lead wire?

Thanks for your help !!!

 

[Bills86e]

Not too far: 727-647-9300.

 

[reelimpatient]

Is it really likely that its the rectifier? I'll pop for one if you think its better than 50% chance of it being that?

any pro or con to buying an aftermarket rectifier instead of OEM?
thanks !

 

[reelimpatient]

No answer on the rectifier?

Also, how in the heck do you get the mpem box open or off the ski to open it?
I think the rectifier is in that box in the front of my 96 gtx 787.

 

[Bills86e]

If it were the rectifier, the ski would not go to WOT, the rpm may go about 5500.

The rectifier IS in the grey box. Pull rearward on the floor shoe latch, then lift box,
slide the box rearward, as the front bottom of the box is slid into a catch, and when
rear is pushed down, gets the box locked into the floor shoe. You remove battery,
then lift box up to about magnito houseing top to open the box. Each side has four
tangs similiar to floor shoe item #28. Ensure the box is completely closed to re-install
it so the front lower fits into the catch on front of the floor shoe, then push down to lock the box in place. Replace any Zip ties you may have cut from secureing the wire looms.

http://partsfinder.onlinemicrofiche..._oem/Seadoo_PWC.asp?Type=18&A=39&B=9&Action=O

 

[reelimpatient]

Well I took it to the lake this afternoon and left it on the trailer. Man is it hard to get to the low rpm carb screws while it's running. Is there a trick or special tool that you mechanics use to adjust them ? I seemed to get it running better, and can full throttle past the bogging range, but the bogging is still there but not as bad.

I guess it's just a carb tuning thing huh ? Or .... What do you think ?

Thanks for the help !