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Discussion Starter #21
Spray cleaner is only good for the outside if the carbs, not so good at getting the varnish out of the passages. Use a fine wire to run through the jets, then blow out the passages.
 

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Thanks, will do tomorrow morning.
 

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Took off the carbs and cleaned out all the jets and everything else. Pretty easy job to do. Put them back on statred right up. I noticed that where the gas leak was it was from the gas lines where it connects to the carb. So I put new lines on. No more gas leaks. Runs so much better. Thanks again for your help. Oh the needle valves were fine no wear at all. Just cleand them along with the seats.
 

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Good idea! Ill put them on tomorrow.
 

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96 bearcat 440fc real hard to start seems to run on 1 cylinder , cleaned carbs,still doing it! get rpm up evens out. got to have idle screw all the way in to keep idling 120 psi both cylinders some times get popping sounds at higher rpm! had installed new cdi, new coil, sat for 3 years installed new used stator got great spark now! so got compression, spark, fuel and timing? any idea as to why its hard to start and some times pops and sometimes runs on 1 cyl.at idle
 

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Seeing as how at higher rpms it smooths out I'd say its in the carburetor. Idling is run by pilot circuit of carb., did you remove pilot jet and pass wire through to clean? I have seen time and time again where they are still partially blocked even though you can see through them, I take the paper/plastic coating off of a bread tie and use that to ream out the orifice of the pilot jet. Also spray carb clean with plastic nozzle on so you have some force through the pilot circuit of carb body while the jet is out, then while its still wet & soft use compressed air to blast out the carb clean and hopefully any gunk thats is built up in carb body. Just a thought.
 

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96 bearcat 440fc real hard to start seems to run on 1 cylinder , cleaned carbs,still doing it! get rpm up evens out. got to have idle screw all the way in to keep idling 120 psi both cylinders some times get popping sounds at higher rpm! had installed new cdi, new coil, sat for 3 years installed new used stator got great spark now! so got compression, spark, fuel and timing? any idea as to why its hard to start and some times pops and sometimes runs on 1 cyl.at idle
Seeing as how at higher rpms it smooths out I'd say its in the carburetor. Idling is run by pilot circuit of carb., did you remove pilot jet and pass wire through to clean? I have seen time and time again where they are still partially blocked even though you can see through them, I take the paper/plastic coating off of a bread tie and use that to ream out the orifice of the pilot jet. Also spray carb clean with plastic nozzle on so you have some force through the pilot circuit of carb body while the jet is out, then while its still wet & soft use compressed air to blast out the carb clean and hopefully any gunk thats is built up in carb body. Just a thought.
 

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Ok.... I replaced my needle and seat assembly in both carbs due to flooding the crank case....I found the problem to the hard starting....my sled is still flooding the crank... even after replacing the needle and seats,What am I missing to stop the flooding??? Any help would be greatly appreciated I just don't know if I got a carb problem or seal and gasket.
 

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Discussion Starter #31
Ok.... I replaced my needle and seat assembly in both carbs due to flooding the crank case....I found the problem to the hard starting....my sled is still flooding the crank... even after replacing the needle and seats,What am I missing to stop the flooding??? Any help would be greatly appreciated I just don't know if I got a carb problem or seal and gasket.
If after checking the choke cable as mentioned int he above post, the next thing would be the fuel pump is allowing fuel directly into the base.
It would only be on one cylinder though (the one with the pulse line on it).
A rebuild kit is cheap and easy fix.

If after all this, it still continues to flood when sitting, add a line shut off valve it ist does not already have one and use it every time that the sled is going to sit for more than a few min.
 

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I don't have a choke...it uses a primer....The carbs have floats but don't seem to be sticking(I've cleaned and recleaned the carbs and the floats glide up and down fine)...I've disconnected the impulse line at the motor and no fuel coming out from fuel pump to end of impulse line..fuel does spray out of the crank where you connect the impulse line to the motor. Does that mean it could still be flooding from the fuel pump into the impulse line or no??? I am going to do a gravity test on the carbs to see if they are still the problem...just because I replaced the needle and seats with new one's doesn't mean they are working correctly. I had new parts before that where bad....just tired of pulling my guts out to get the fuel out of the crank....is there an easy way to it other than pulling your guts out??? Thanks guys and I know it's probably a stupid petty solution but I haven't dealt with this problem before
 

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I don't have a choke...it uses a primer....The carbs have floats but don't seem to be sticking(I've cleaned and recleaned the carbs and the floats glide up and down fine)...I've disconnected the impulse line at the motor and no fuel coming out from fuel pump to end of impulse line..fuel does spray out of the crank where you connect the impulse line to the motor. Does that mean it could still be flooding from the fuel pump into the impulse line or no??? I am going to do a gravity test on the carbs to see if they are still the problem...just because I replaced the needle and seats with new one's doesn't mean they are working correctly. I had new parts before that where bad....just tired of pulling my guts out to get the fuel out of the crank....is there an easy way to it other than pulling your guts out??? Thanks guys and I know it's probably a stupid petty solution but I haven't dealt with this problem before
I am having a similar problem. I have read all sorts of possible problems and have not narrowed mine down. My sled starts great on cold starts, idles fantastic, runs like a bat out of hell but when i shut it down and try to start it warm, it will not start or will sputter and stall out. I dont understand it. Could it be running too rich? What does this sound like to you all? Help please. I am a beginner sled owner.
 

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96 bearcat not starting

here is what i got! 440 air cooled! 120psi per cyl, new plugs, new coil, new cdi, new/used stator has good spark now! carbs were fully disassembled and soaked in 100$gallon carb cleaner for 1 week and blown out with compressor before reassembly, mixture screws set at 1 turn where they were before disassembly, and i didn't mess with throttle or choke cable settings have to keep throttle screw all the way in to keep running! also need to slightly crack throttle to get started but it still won't start unless i prime it 2 times and leave choke off then it seems to intermitently fire on clutch side cyl. and runs strong on flywheel side although flywheel side heats up and clutch side stays coolto touch! any idea's i dont think its a carb problem but i have taken them off again and am soaking again day 3 now!
 

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Discussion Starter #36
I suggest an inline spark detector to see if that plug is firing under pressure.
Either no spark, or too much fuel on that cylinder.
 

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Well I've done a lot of checking and rechecking on both my carbs...I found the following. My pilot jet is 310 on one carb and 290 on another and all four floats have different number's stamped on them. Is this a start in the right direction? Is a 290 bigger than a 310 or smaller??? I'm just wondering because if I'm right the wrong jet can cause it to over flow down the piston into the crank...:dunno: Any body know for sure??
 

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Those #'s are for the MAIN jets and the larger the # the larger the jets orifice/size, your pilots will be the smaller jets that are usually along side the mains, more recessed into the carbs body and are smaller in overall size then the mains and have #'s like 15, 17 or 20 in that general size area NOT triple digit #'s like the mains unless they have a 1/2 size such as 17.5
 

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Thanks for the correction...That's what I ment to say....will the two different main jets cause a flooding problem...the sled oem is 310
 

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Took my sled out this weekend and noticed at about 1/4 to 1/2 throttle it seem to be flat. but once you went to 3/4 it picked right up and ran great. idles fine. Just wondering if you have any idea why its like this?
 
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