What else can cause a rich condition?

M

marz831

Location
FL
Boat is rich at about 25% throttle. If you hold the throttle there, it will slowly drop in RPMs and will sputter when you nail the throttle. Definitely rich. Gets worse when motor warms up. Plugs have very little color (only the tips are dark and wet). The ski is rideable and as long as you vary the throttle, it runs fine.

I have tried TONS of jetting/pop off combos and it never seems to get any better. Could it be something else?
 
Speedfreak

Speedfreak

Location
So. IL
Tell us what your setup is and what you have tried and see what where we think you should be.

Also have you done a leak down test? I had a leaky motor and I tried for a year to get the thing dialed in. I tried everything I was going to replace the carbs. After I found my leaky cases I dialed it in 2 times out.
 
M

marz831

Location
FL
B-pipe limited
TLR 48 Carb - basically just a 44 with the bottom bored to 48
Riva conversion manifold

Have tried:

Pilots 112.5-120
95 and 115g springs
2.0 n/s
135-145 mains

Also went down to a 1.5 n/s and got similar results except it seems to have lost some bottom end with the 1.5

Wouldn't an airleak cause a lean condition?
 
Speedfreak

Speedfreak

Location
So. IL
marz831 said:
Wouldn't an airleak cause a lean condition?
Click to expand...


Yes if you are dialed in and then get an air leak but if you are trying to dial it in then it just makes it a nightmare to get it right. I rejetted my carbs every weekend for a year. I dropped 3 main jet sizes when I got the cases sealed.

But sorry I can't help you with the jetting on a single carb. Do you have a pop off gage. They can be built for about $10 and an old bike pump.
 
M

marz831

Location
FL
Actually, if I made block off plates for the intake and exhaust could I use a pop off gauge on the pulse fitting to pressure test? How much pressure should it hold and for how long?
 
M

marz831

Location
FL
Ok, so tonight I went through the carb again. I cleaned some junk out of the internal filter, I cleaned out the external filter, I bypassed the fuel selector, and I went back to the jetting that has been the "best" so far. I was finished when I fired the ski up to get fuel back in the lines/carb. I did this with the f/a off. Take a look at the pics below. The butterfly and the inside of the carb was CLEAN before I started the ski and revved it to about 1/4 throttle. Is it just me or does it look like the carb is dribbling fuel all over the place?!

By the way, the new gallery features rock!

 
SUPERTUNE

SUPERTUNE

Race Gas Rules
Location
Clearwater Fl.
Where's all that goo coming from! You need to completely remove tank and clean entire fuel system and remix new fuel and oil. It should never look like that!!! Double check to make sure your adapters are tight also. Get some really good 1/4 inline filters too, I use hi-flow paper motorcycle ones.
 
M

marz831

Location
FL
Chuck, it's not "goo", it's just gas. The pictures makes it look blacker than it really is. It seems like the carb is just spewing out fuel at about 1/4 throttle. This is exactly where it starts to load up if you hold the throttle there. This carb has done this from day 1. Is is possible that the carb is no good? Or is there something else that could make this happen?
 
Speedfreak

Speedfreak

Location
So. IL
Sounds like a bad needle valve or pop off too low. Asking the obvious... when you done a pop off test how was the pop? Nice and crisp? What is your pop off set at?
 
M

marz831

Location
FL
Pop off is 32 psi. I've tried multiple needles with the same result. I'm seriously considering just trying another carb.
 
LegDragger64

LegDragger64

X
Last night while running the SJ with the arrestors off in the garage i could see a steady stream of gas flowing from the primer , two year old bulb type primer. I had been ready to tear the engine apart and It sure is good to find out the problem with a ski will only cost $20 to fix.
 
WFO Speedracer

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
I noticed you said you tried multiple needles,did you just replace the needle or did you replace the needle and the seat,the o-ring around the seat could be leaking,does the needle hold pressure when you do the popoff or does the gauge leak down slowly,it should hold at least 5psi of pressure.
 
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