New B-pipe help

M

marz831

Location
FL
Installed my limited pipe today, took the ski out and performance was very inconsistent. Half the time I would hit the throttle and the ski pulled very hard. The rest of the time it seemed like it did not want to go, but eventually it would rev up. A couple times it would fall flat on its face and die at low speeds. It seems like the pop-off is too high, but it is set up exactly to the FPP specs. The ski is all stock other than the pipe and two screens removed from the F/A. I have the bottom and middle screws closed. Top is open around 1/4 or so. Engine temp seems ok, pipe temp seems a little cool.

Here is my carb setup on stock 38's

70 pilots (stock)
135 mains
stock n/s
stock spring
1.25 turns out on lows
1.5 turns out on highs

Any ideas?
 
FLY6584

FLY6584

Location
Clearwater, FL
Well FP calls for a 95g spring and depending on the year of your ski you could have the 95g spring as your stock spring or the 115g spring as your stock spring. I would make sure you have the 95 in there.

I would also consider running a 72.5 pilot. Before I sold my superjet it had an occasional slight lean bog and I recommended to the buyer that he try a 72.5 and he did and he said it runs awesome now without any hesitation.

good luck:biggthumpup:
 
M

marz831

Location
FL
The ski is a 97, but the carbs are very new (they had the tamper caps on them). Do the newer SJ's (04-07) have the 115 spring?
 
Crab

Crab

thanks darin...noswad!
Location
Seattle
marz831 said:
Installed my limited pipe today, took the ski out and performance was very inconsistent. Half the time I would hit the throttle and the ski pulled very hard. The rest of the time it seemed like it did not want to go, but eventually it would rev up. A couple times it would fall flat on its face and die at low speeds. It seems like the pop-off is too high, but it is set up exactly to the FPP specs. The ski is all stock other than the pipe and two screens removed from the F/A. I have the bottom and middle screws closed. Top is open around 1/4 or so. Engine temp seems ok, pipe temp seems a little cool.

Here is my carb setup on stock 38's

70 pilots (stock)
135 mains
stock n/s
stock spring
1.25 turns out on lows
1.5 turns out on highs

Any ideas?
Click to expand...
I think the main is open way too far and causing you to have to "clean out" before it runs right. Their site shows 1/2 turn on the high adjuster, but work it in slowly to see how it responds.
 
M

marz831

Location
FL
I'll switch to a 95gm spring and see what that does, and if i still have problems I will start working in the high speed adjuster.

Thanks!
 
M

marz831

Location
FL
Looks like you were right Dan, pulled the carbs apart and there were 115 gold springs in them. I am going to try to dig up a couple 95's and give that a try tomorrow.
 
Crab

Crab

thanks darin...noswad!
Location
Seattle
marz831 said:
I don't have a gauge. I'm going to give the 95's a try. If it still doesn't feel right, I will pick up a gauge.
Click to expand...
Don't change the springs with out checking with a popoff guage, they will for certain almost always be different . Test before changing and after.
 
Speedfreak

Speedfreak

Location
So. IL
I used an old bicycle pump a 1/4 inch "T" and put a gage on the end of the "T". It might not be dead on accurate but it works. I checked the gage with all the other gages in the garage and it was pretty close before taking the unit apart. The gage is a 60 PSI tire gage for under $5 at walmart I unscrewed the end off of it and clamped the threads into the hose. It might be really late or something but I don't think that makes a lot of sense so I drew a very crude picture.
 

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Jr.

Jr.

Standing Tall
Staff member
Site Supporter
Location
Hot-Lanta
marz831 said:
Installed my limited pipe today, took the ski out and performance was very inconsistent. Half the time I would hit the throttle and the ski pulled very hard. The rest of the time it seemed like it did not want to go, but eventually it would rev up. A couple times it would fall flat on its face and die at low speeds. It seems like the pop-off is too high, but it is set up exactly to the FPP specs. The ski is all stock other than the pipe and two screens removed from the F/A. I have the bottom and middle screws closed. Top is open around 1/4 or so. Engine temp seems ok, pipe temp seems a little cool.

Here is my carb setup on stock 38's

70 pilots (stock)
135 mains
stock n/s
stock spring
1.25 turns out on lows
1.5 turns out on highs

Any ideas?
Click to expand...


FPP jetting specs are slightly off............
Change your pilot jet to a 75
Keep all the other settings you currently have.
Do not mess with the pop off on the oem 38's
Run the stock N/S & spring...... they need to run the high setting!!

Your water setting should be

3/8 top
1/4 mid
Bottom closed

Now go have fun!!!!


ski ya, Paul
 
M

marz831

Location
FL
Still having issues getting beyond 25% throttle, response was better but not quite there. I am going to try the 95gm spring. If I end up too rich, I'll step back to a 72.5 pilots.
 
Last edited:
Watty

Watty

Random Performance
Location
Australia
Sounds to me like you have too much water going into your pipe.

Try the bottom screw 1/8th open and ride and see if that makes any difference. I use the same settings as Paul suggested above, but it's always nice to do the elimination thing to find out where your problem is.
 
M

marz831

Location
FL
Would incorrect pipe settings cause you to be able to hold the throttle wide open for 20-30 seconds without going above 25% throttle or so? I thought for sure it would be a carb issue.
 
Jr.

Jr.

Standing Tall
Staff member
Site Supporter
Location
Hot-Lanta
marz831 said:
Would incorrect pipe settings cause you to be able to hold the throttle wide open for 20-30 seconds without going above 25% throttle or so? I thought for sure it would be a carb issue.
Click to expand...


???? 20-30 seconds is quite a lot of time??? You were origionally saying a second or two?? in order to help with your problem, please give an exact describtion................??

if in fact your current describtion is acurate, You have way more problems than just carb adjustment!! :bigeyes:
 
M

marz831

Location
FL
The first time I start the ski, it takes quite a bit of feathering the throttle, sometimes up to 20 seconds or so before the the ski will go above about 25%. Once it takes off the first time, it will only hesitate a second or two. After shutting it off, the same thing starts over. As long as you keep it running it doesn't really feel like it is that far off.
 
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