My 1996 SPI Resto

[racerxxx]

I don't quite get the transmission fluid test but it can be difficult sometimes to get the holes and passages clear and there is no way to positively check 100%. I'd like to see the pump rig.

So, you take a can like this. Fill it with atf, put the nozzle in the internal ports (see mikuni side cut drawing for port flow) and squirt. You'll see exactly where the red fluid flows, like those little micro holes in the carb throat. It's a actual visual confirmation that you have flow going thru all the ports. It's very, very simple. It has never failed me.

 

[racerxxx]

Just disconnect the line going to res on the baffle. Run a new line straight to the carb inlet, run a filter inline. I'd leave the rest alone.

 

[Seadoo Tuner]

Just disconnect the line going to res on the baffle. Run a new line straight to the carb inlet, run a filter inline. I'd leave the rest alone.

Don't have extra line so that's why thought of taking carb inlet from water seperator in and moving to RES.
Won't there be a possible air leak if "ON" hose to fuel selector is not disconnected at the baffle and capped?

 

[Seadoo Tuner]

Just got back from going to the lake for a 30 minute test ride with the selector and water seperator bypassed - bog was still there but not quite as bad. With the bypass there seems to be a bit more power, or maybe it was just my imagination.

Will be ordering a genuine carb rebuild kit, JSP has the genuine mikuni kit with needle and seat as well as base gasket for $71.95 but the pic shows both a non red middle piece for the diaphram in the kit (which I have seen means its not genuine) and one with red piece in the same pic with parts in an expanded view to the left so is the red middle piece an indicator of a non genuine mikuni carb rebuild kit or not? :

 

[mikidymac]

Just buy from OSD Seadoo, one stop shopping and guaranteed to be the correct genuine parts.

 

[Seadoo Tuner]

Just buy from OSD Seadoo, one stop shopping and guaranteed to be the correct genuine parts.

Thanks, before ordering, I'm trying to figure out the needle size needed for a 96 SPI 587 - Seadoosource website and some listings show a 2.0 but stock is apparently a 1.2. Seadoo p/n is 270 500 208 which some listings show the 2.0 needle they sell is a replacement for that part number. Has the 2.0 needle superceded the 1.2? Confusing.

Can you shed light on whats really required for the needle size?

 

[mikidymac]

Yours takes the 2.0. I just checked the parts diagram for a 1996 SPI...
Ref:
40
270500208
Needle Valve 2.0
MSRP: $29.99
Dealer Price: $25.49

 

[etemplet]

I didn't look but it is most likely a single carb. My SPI was a single so hence the larger seat size.

 

[Seadoo Tuner]

So OSD sells 3 types of the 2.0 Needle :

A push in type "quality" aftermarket
A screw in type "quality" aftermarket
One apparent oem?(but doesn't state) showing p/n 275500208

3 choices, the one in my carb is push in, I assume these all come with the seat as well?(description is needle valve)

 

[mikidymac]

You can use amazon too.

 

[Seadoo Tuner]

Found a local Mikuni distributor at the last minute and just got back from picking up the 2.0 Needle Valve.

Will be picking up some Felpro gasket paper Monday at the local auto parts store to cut out my own carb to intake gasket (no local source for them).

 

[Seadoo Tuner]

Needle and seat was $16 and comes with 2 springs, a 80gram and a 115 gram, silver and black.

 

[mikidymac]

Never seen that kit. Awesome that it comes with the 80 gram.

You might have to start reselling them here [emoji6]

Is there a part number in the back of it?

 

[racerxxx]

Never seen that kit. Awesome that it comes with the 80 gram.

You might have to start reselling them here [emoji6]

Is there a part number in the back of it?

It's right there on the paperwork

Mk-BN 38 NV

THEN then 44NV 1&2 are a 2.3 and a 2.5 needle. It's great it comes with the spring required in the first kit.


Mikuni Needle Valve Repl Kit SBN 38 MK BN 38 NV for sale online | eBay

 

[mikidymac]

It's right there on the paperwork

Mk-BN 38 NV

THEN then 44NV 1&2 are a 2.3 and a 2.5 needle. It's great it comes with the spring required in the first kit.


Mikuni Needle Valve Repl Kit SBN 38 MK BN 38 NV for sale online | eBay

Well, yes if you zoom in, LOL.

 

[Seadoo Tuner]

So the kit comes with a black 80 gram spring for 21 lbs popoff and a gold 115 gram spring for 32 lbs popoff, which do I use for a 96 SPI needing 21-37psi and 14 minimum stabilized pressure

 

[etemplet]

32 psi would be my choice. It's gonna be rich at 21.

 

[mikidymac]

Neither of those springs your's takes the 95 gram spring.

 

[Seadoo Tuner]

Neither of those springs your's takes the 95 gram spring.

So the dull silver 25psi one, guess I should leave the stock one in then as I don't have a dull silver in the kit unfortunately and have read its recommended to use the old spring anyway.

 

[Seadoo Tuner]

So took my airbox off and the fire arrester housing as well and see this (all screws loose and one ready to fall in the motor), guess the last 3 hrs riding last 2 times out shook them loose and lucky one didn't fall down the carb.

 

[Seadoo Tuner]

So got the carb off and I checked the high and low speed screws and high was out one turn (should be zero according to seadoosource website) and low was out only half a turn instead of the 1 and a 1/4.

Carb is off now and disassembled to be cleaned again and new needle and seat installed.

 

[Seadoo Tuner]

Spring inside the carb seems to be the wrong one, the correct 95g dull silver one is 15.7mm long, the one in the carb is more like the shiny silver 65g one which is 14.6mm long :

Wonder what would the effect be if the black 115g spring with a 32 popoff was used instead, or, on the other end of the spectrum a 80g spring with a 21 popoff since popoff for the 96 SPI single carb is supposed to be 21-37 popoff.

 

[mikidymac]

If your ski is stock use the correct stock carb parts and settings. The only thing you are going to gain by mixing and matching is headaches.

 

[Seadoo Tuner]

If your ski is stock use the correct stock carb parts and settings. The only thing you are going to gain by mixing and matching is headaches.

New spring is 3 weeks out at my local distributor, if I use the black 80g 21psi spring in the meantime and can get to 24 or 25psi popoff by bending arm slightly should this be ok for temp fix? Dull silver 95g spring is spec'd at 25psi popoff with my SPI and 2.0 needle so thinking it should work if popoff is the same?

 

[etemplet]

I like to stay between 60-75 % of the top figure. in the pop-off range I don't like going below 50%. as some carbs tend to get too much fuel below that. I spent a lot of time with my GTXs testing different pop-off settings. People might not agree but that's my numbers. Good Luck !!