Contradicting carb settings

[jwall116]

The repair manual for my GSI shows 1 3/4 turn on low and 0 on the high.

Seadoo source shows 1 1/2 on Low and 1 on the high.

Initial tune and riding has the low at 1 3/4, ran terrible at 1 1/2 and the high at 1 turn out.

Which is right? Would the ski load up/run terrible if the high was 1 turn out vs 0?? I'd rather foul plugs and save an engine than be lean! Has about 2 hours of WOT with it the way it is, haven't looked at plugs to check it.

 

[pwgsx]

Its probably because you have them adjusted wrong............It should be 1 Low, 1.5 High. Always do a plug check so you know if you are running lean. Also did you set your pop-off?

 

[jwall116]

 

[pwgsx]

From sea doo source :
1997
GTI
717
270500297
N/A
BN-40I (SB)
MAIN-175 PILOT-67.5
1.5
270500267
23 - 43
LOW- 1 HIGH- 1-1/2

 

[pwgsx]

From SBT:
1997 Sea‐doo GTI 23*‐ 43 LOW‐ 1*HIGH‐ 1‐1/2

 

[mikidymac]

Most seadoo's run the High at 0 turns out for stock settings.

The manuals are written before the skis hit the market and sometimes the actual settings are different. Seadoo source is pretty good.

It is better to be rich and go down from there.

 

[pwgsx]

Perhaps the manual you have is not the one for your exact model year? Some had 2 carbs, others had only 1 carb in different years so the settings would be different. The BN40i I thought had a acc pump? Does yours?

 

[jwall116]

The manual I have is a digital one and states quantity of carbs as one.

I mistyped in my first post, currently it is at 1 1/2 on LOW and 1.5 High. It did not idle well at 1 turn out on low. Had a very long slow return to idle 1 turn out.

Anyone with this ski have some input?

The low is pretty strait forward to adjust.. but the HS needle. Do i leave it at 1.5 or go to 0? I will pull plugs when I get home but this seems like a huge difference in settings..... Even the jet sizes are different. Main is the same but pilot is smaller on SDS.

 

[mikidymac]

Well the book calls for a 70 pilot and 175 main with LS = 1-3/4 and HS = 0.

Does that match the jetting in yours?

I am not sure where SDS got their info but they are typically correct.

The HS screw will not change the idle or starting.

 

[jwall116]

I did not change the jets when I tore down the carb. Heavy cleaning, new needle and seat and OEM carb kit.

Would you leave the HS needle at 1.5 out or lean it down to the book?

In your experience, if the HS needle was 1.5 turns out instead of 0, would it load up and fall on its face at WOT or is the adjustment pretty minimal in change of fuel flow?

The ski idles well, WOT is giving me 52 MPH and seems like consistent RPM. No real way to tell unless its glass smooth....

At 1/8-1/4 throttle the engine has a slight vibration it develops. No hesitation what so ever no matter where I am in the throttle when I transition to WOT.

 

[mikidymac]

Seadoo sometimes changed the jets and that caused a change in the screw settings. IF you could confirm what jets you have then you could match that to either the screw settings from SDS or the manual.

If it loads up at WOT try pulling the choke a little when going WOT and if it gets even worse you know you are already rich. You could also drop it to 1.25 to see if it gets better or worse.
My suspicion is that it should be at 0 but I would hate to see you smoke the engine.

 

[jwall116]

Considering it ran terrible with the low at 1.0 turns out, and runs great at 1 1/2-3/4, I think the manual is the correct one here.

Myself and the misses ran it pretty much WOT the entire time out last weekend. Never missed a beat. Seemed to me... mr OCD (isnt that what this forum really is for) that upon blasting in to the no wake and chopping the throttle the engine kind of went HEY MR OCD, IM RUNNING RICH! Meaning a little blurbliy but not fouling...

I could always go immediately back to WOT with zero hesitation.

I'll pull the plugs after work, they were brand new prior this weekends run.

 

[jwall116]

 

[mikidymac]

Plug readings, unless you do it absolutely perfectly correct those plugs won't tell you much.

That being said they are on the safe rich side.

 

[jwall116]

The settings get even more commical !

SBT says:
SPX/GS/GSi/GTS/GTi - Low Speed – 1 +/- 1/4
High Speed – MAG 0 PTO 1/4

I only have 1 carb .....

Mikidymac -- From your experience.... How effective is the HS needle? From my understanding on our carbs the needle supplies extra fuel AFTER the main jet. Meaning 0 turns out is on the jet per factory.

With that said. What would you personally do in my situation?

I am a fan of slightly rich, not 100 more rpm. I dont want to be filthy rich as to load up plugs or get bad performance. I will continue to run ski and 'feel' her out but for now... 1.5 on the high as it is or 0 ?

 

[mikidymac]

I would go by the manual. Your plugs look rich and a lot of the Seadoo's run 0 on the high that is compensated by the main jet.

I don't trust SBT on anything and I personally know the SDS does have some errors.

The HS screw does make a difference but only in the upper throttle range.

I can tell you the stock settings work 100% of the time on a stock ski. The only exception is if something else is wrong.

 

[jwall116]

Thanks mang !

What part of cali are you in? I'm originally for Torrance, also lived in San Diego for a few years. After 22 years in cali I moved to HOUSTON... not for the weather.

One of the plugs had a small droplet of moisture on it... broken exhaust bolt causing a little water into the intake or is this normal condensation?

I ordered a new used manifold for mineekota, WILL be on the water Monday/tuesday. These 80 degree days are killing my soul being away from the water.

 

[WhiskeyD]

You need to verify what size Jets are in your carb. I believe the difference in recommend carb settings is because they used different jetting in different 720 setups. Some have an accelerator pump too which would change the jetting as well.

 

[jwall116]

I am not removing the carb again until it's time for rebuild

Mine does have the accelerator pump.

 

[mikidymac]

Thanks mang !

What part of cali are you in? I'm originally for Torrance, also lived in San Diego for a few years. After 22 years in cali I moved to HOUSTON... not for the weather.

One of the plugs had a small droplet of moisture on it... broken exhaust bolt causing a little water into the intake or is this normal condensation?

I ordered a new used manifold for mineekota, WILL be on the water Monday/tuesday. These 80 degree days are killing my soul being away from the water.

I am on the central coast about an hour north of Santa Barbara.

A little condensation is normal and for some reason the 951's get a lot. That is the main reason I fog all my skis after every ride unless I am going out the next day.

 

[jwall116]

Do you use the brp stuff or something like the sea foam fogging spray version?

 

[mikidymac]

I buy the big can of Klotz FogOn. I think Amazon sells it but I get it through Rocky Mountain ATV. Any fogging oil is fine though. I think Walmart even carries one.

 

[jwall116]

Thanks for the help. Get back to that project ski!

I'm going to do 1/2 turn out on the high to be safe. A little rich is safety in my head. Will test run Tuesday. New truck Monday. F-150 2.7l eco boost. Sick and tired of my 14mpg Silverado!

 

[mikidymac]

I am going to do a little on it today. Those are nice trucks. I just looked at a friends brand new F150 platinum last night. Pretty sweet.

 

[TLH101]

The SeaDoo spec book, published 2003 states low @ 1 +or_ 1/4, and high at 1 1/2.
That's for a '97 GS (5621) & GSI (5622).