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Discussion Starter #1
I have a Walbro WF-1B carb with problems. I just had it rebuilt and apparently can't get it adjusted. I have it on a Kawasaki 440. It starts up great every time, but bogs down every time I hit the gas. It never will open up. I have adjusted the high speed and idle screws on the top every way but Sunday with no luck. What am I missing here?
 

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Well I just ordered a carb kit for my 399 cheetah.
Should be interesting???

I hope you find your problem.

I rebuilt a tilson carb, one pull it would run, now all of a sudden, it won't suck up any gas, Ill have to tear it down, I guess.

Good luck
 

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I should mention that I am getting WAY too much fuel to the engine no matter how I adjust the two screws on the top of the carb. Fuel is even coming out of the intake. Is there something else to adjust? It has a fixed high speed jet located under a brass hex cap, but I would have thought that would be cleaned and/or replaced during the rebuild(?). I'm not a big fan of Walbro after this episode. I do have an old Tillotson HD87A from a Kawa 340 that I think works on the 440, too. Maybe I should swap the carbs altogether and beat the hell out of the walbro with a baseball bat. HELP ANYONE!
 

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Hey pantherpride,
I'd say try the Tillotson carb and see if it corrects the problem. The HD should be the same mounting spec. as the WF. Start the low and high speed screws at about 1 1/2 turns out and adjust them as needed. I use to replace the carbs with a Mikuni BN diaphragm carb from Chaparral and they worked so much better. Now adays I don't think you can find them. It would have been so much easier if the early sleds came with Mikuni slide valve carbs. Good luck!
 

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Hey pantherpride, ive got a kawi 340 with a walbro aswell, i had it working fine, the thing would lift the skis EASY, but later i found out a mag oil seal was leaking, so ive rebuilt the engine, and decided to rebuild the carb while im at it, should be back together by the end of the week, well see how it goes...
 

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The needle is not seated properly or is stuck open and the fuel is going right through the carb. I would try to put a mikuni round slide carb on instead of the walboro or tilitson carb. they ar a pain in the butt. you have to constantly put diaframs in them and the needle valves always stick. i put a mikuni on my 399 rotax and also on a friends 300 rotax and they ran alot better.
 

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We used to have a '79 Scorpion Whip 440 that had a Walbro. It was hard to start no matter how we adjusted it. It often was tough to get it to not run rich no matter what we did. And you often had to goose the throttle while you were stopped because it didn't want to idle. Baseball bat sounds like a winner.
Originally posted by pantherpride
[br]I should mention that I am getting WAY too much fuel to the engine no matter how I adjust the two screws on the top of the carb. Fuel is even coming out of the intake. Is there something else to adjust? It has a fixed high speed jet located under a brass hex cap, but I would have thought that would be cleaned and/or replaced during the rebuild(?). I'm not a big fan of Walbro after this episode. I do have an old Tillotson HD87A from a Kawa 340 that I think works on the 440, too. Maybe I should swap the carbs altogether and beat the hell out of the walbro with a baseball bat. HELP ANYONE!
 

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Discussion Starter #8
Since I don't have a Mikuni on hand, I am trying the switch from Walbro to Tillotson. I connected the main fuel line to the bottom of the bowl and the impulse line to the fitting on the side of one of the bowl plates. However, there is still one fitting I don't understand. According to the Tillotson HD diagram I found, they call it a body channel elbow connection. It looks like a regular size fuel fitting, except it has only a pin size hole in the end. What do I do with this?
 

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The the fitting you are talking about is probably the return line. All tillotson carbs I have ever seen have a return line that feeds back into the tank, so if you have your main fuel line on the screw in filter on the bottom of the carb and the vaccum line hooked up all that is left over is the return line.
 

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Discussion Starter #10
Canadian redneck...that's pretty damn funny. I guess I qualify for Wisconsin redneck. Anyway, if that's the case, how will I manage that if the only fitting on the tank is being used to draw fuel to the carb? Can I get away with plugging it or does the return fuel have to go somewhere?
 

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It goes back to the fuel tank.
 

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OK. Here is the scoop. The air bleed screw is the one with the larger head that is on the top and closest to the engine. The small one immediately next to it is the low speed mixture screw.Start with that one set at 1 and 1/4 turns open from the seated position.(turning low speed mixture screw clockwise leans the mixture)
Some models of the WF carb do not have an air bleed screw. If it does, set ti at 1/8 to 1/4 open initially and then adjust if necessary after engine is warm and low speed mixture is adjusted for smoothest obtainable idle. Turning the low speed needle clockwise richens the mixture. Adjust idle speed stop to desired rpms after idle mixture has been set.
High speed mixture jet is fixed on most models. If there is an adjuster screw present, start with is set at 1 and 1/4 turn open from the seated position.

When the carb was reassembled, with the unit upside down, the floats should be 1 to 1/16th in (measured at the bottom of the float) abouve the gasket of the carb body. the float balance spring should be pre-loaded 1 and 1/4 turns in to close valve. Float height is adjusted by bending float lever.
Fuel pump uses two neoprene check valves. Renew valves by pushing stem out from back side of plate.

Hope that this is helpful.
 

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Yes, you have to have a return line going back into the tank or else you will have fuel squirting everywhere and you cant plug it either or it will not work. Take the tank out, drill a hole in the top and put in a fitting. I Drilled a hole in my old sled tank and pressed in a fitting off of another tillotson carb I had around. Also on my old go-kart I drilled a larger hole and got a screw in type fitting and put it in the top.
 

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Discussion Starter #14
RJG (er, OldCatRider)...thanks for the insight. After considering a change to a Tillotson, I decided not to since I need a return fitting on my tank. I've seen tanks this vintage with a fitting on each side, but not mine. Anyway, trying to understand your instructions, I took the bottom of the Walbro off to check the float level. It seemed close to what you suggested (I can tell previous owner had bent the float lever a number of times!). I looked closely at the float spring and saw that it was serving no purpose the way it was installed. You said it should be pre-loaded 1-1/4 turns, so I did. Now, the float presses gently against the lever, even when I turn the carb right-side-up. If I had turned the carb upright before, the float would have just swung down allowing the valve pin to drop. Do I now have it set correctly? Would this be the too-much-fuel problem all along? Please tell me yes!
 

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YES!
 
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