Fuel screw adjustment

viperino

viperino

New member
Joined
Feb 7, 2005
Messages
174
Location
Welland, Ontario
Had the carbs out for cleaning and made a small adustment to the fuel screw....turned them in a bit to 1 and 7/8 because they were about 2and 1/4 out(which was what dealer set at). Well now i'm getting a bad low end bog when i crack the throttle from a stop.
i have researched this a little and figure i need to turn the fuel screw back out cause i think it's a little bit lean.

My question is has anyone figured a way to adjust the fuel screws without taking the carbs out. And if you have, you might be worth alot of cash right about now.

The other question i have is what are the consequences if the fuel screws are out too far?
 
Last edited:

Fun eh. I think you have to take them off.
Screws being out to far, maybe poor fuel mileage but its really only in its idle curcuit. Not really.
To back up, what are your screws set to now? Were they at spec before and did the sled run fine?
I would screw them in till lightly seated then back out to spec.
Did you do any thing else to the carbs ( floats ) did you put everything back together correctly? are the boots put on correctly?
 
i am pretty sure the viper carbs set the fuel screw at 2 and 1/8 or so from factory.....you are getting a lean bog now....take the carbs out again and open em up to stock or a little more....if your sled hangs up after coming to a stop then they are not far enough out.....daman has a great posting on this and what affect it has.....as for setting them the only way is to remove the carbs....unless you buy remote fuel screw adjusters...or make some....doing this is on the tech pages....
 
Just the nature of the beast, start pulling 'em my friend, you just can't do a good job of synching them in the sled.

try 1 7/8 or 2 out..
 
error in my original post....i have them set at 1 7/8 right now(not 1 1/8). I turned them in slightly when i did the carbs.....they were at about 2 1/8 and never had problems at that setting so out comes the carbs...again

the reason i turned them in is because i thought the factory setting was 1 7/8.

I have edited original post.
 
Last edited:
ya what daman said...hehe make sure the boots are on....i bought a srx mountain dirt cheap because the guy folded the boot over and toasted all 3 pistons and 2 cylinders....its an expensive mistake....
 
i have readjusted the fuel screws to just over 2 1/8...although low end bog problem very much improved, still noticing slight hesitation when i crack the throttle from idle (completely stopped). I havnt been able to snow test it yet......should i come out with the fuel screws a little more or is this hesitation(very slight) normal or maybe another problem somewhere else?
 
Last edited:
viperino said:
i have readjusted the fuel screws to just over 2 1/8...although low end bog problem very much improved, still noticing slight hesitation when i crack the throttle from idle (completely stopped). I havnt been able to snow test it yet......should i come out with the fuel screws a little more or is this hesitation(very slight) normal or maybe another problem somewhere else?
Click to expand...
are you all stock?????
 
ya pretty much stock except for clutch.....53/43 helix with green secondary spring and some additional weight in the primary.

sled has 8000kms and still running with original weights and sheave bushings.....wondering if hesitation may be result of some worn clutch parts
 
If your stock and your out 2 1/8 out now that far enough. we need to find out if your bog is lean or rich,try hitting the choke when she bogs,if it come out of it or doesn't do it it's lean..
 
when i give it half choke before cracking the throttle, i don't get the bog....just to confirm, this means its lean and i need to come out a little further with the fuel screws... correct?
 
Are you sure you cleaned AND blew with shop air the P/J's out good?,you when held up to a light you could seen the light through them??

2 1/8th is getting awful far for stock..thats telling me the P/J's aren't flowing like they should.
 
I'll second the above notion...I cleaned the carbs on my SRX last night since 2 P/J's were completely blocked. Nothing short of my 120psi shop air got them fully clean. Take a wire and poke it through too....one looked clean at a glance, but further exam showed it about 1/3rd blocked still.

Next time I'm just buying new primary jets....I'm not sure it's easy to ever get them 100% clean, and the remains of the debris clinging to the sides can potentially attract dirt no matter how miniscule....probably why this is so frequent on these sleds, the small diameter notwithstanding.
 
Last edited:
You must log in or register to reply here.


Back
Top