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Discussion Starter · #1 ·
on my 99 xc 700 im getting closer to getting it running i had it running today find and great getting ready to take off to hit the trails and my sled stops getting gas on the clutch side all the lines have been replaces even in the tank with a new filter, fuel pump is rebuilt and tested and working, the carbs have been cleane..it ran find and started alright now i have a hard time starting it..so what can be the problem i took the line off the carb and im getting gas through the line so im wondering can it have a stuck float thats my thought but not sure how to solve the problem or should i replace both my jets just in case im lost here i been having gas problems now for some time now im getting gas on one side but not the clutch side
 

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Pull the pto carb off the sled, take the float bowl cover off the bottom, put a piece fuel line on the inlet tube, hold the carb upright and blow into the hose connected to the carb, with the float hanging you should be able to blow air though the carb, when the float is pushed up the needle/seat will not allow air to pass through, if no air can pass with the float hanging then I am suspecting that the fuel passage is clogged, you will have to remove the float and needle/seat and take a fine piece of wire and run it through the passage to make sure it is clear, once you do this reassemble the float and needle/seat and do the air test again.
 

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Discussion Starter · #4 ·
98700xc said:
Pull the pto carb off the sled, take the float bowl cover off the bottom, put a piece fuel line on the inlet tube, hold the carb upright and blow into the hose connected to the carb, with the float hanging you should be able to blow air though the carb, when the float is pushed up the needle/seat will not allow air to pass through, if no air can pass with the float hanging then I am suspecting that the fuel passage is clogged, you will have to remove the float and needle/seat and take a fine piece of wire and run it through the passage to make sure it is clear, once you do this reassemble the float and needle/seat and do the air test again.
With the floats hanging I should be able to blow through the line correct and if tip it up side I shouldn't be able to to blue through it?
 

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Discussion Starter · #5 ·
And sorry for the spelling I'm doing this on my phone but yes I checked this the other day and air was passing through so its not plugged I checked this bc I thought maybe the float was allowing gas to go back through the lines that's why I was having a hard time starting it the.next day....but one minute ill hey has and it will run great then just stop ..I'm getting good spark good compression good gas through the line and I already checked my crank seals
 

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Maybe switch the output lines on the fuel pump. That fixed ours oddly enough, one side put out a little more pressure than the other and since it didn't have to push as far it ran perfectly.
 

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Discussion Starter · #8 ·
well nothing still replaced all the lines again to better stuff i tried to do eveything and wassnt getting gas in either of them so i took the line off the feul filter and by passed it then i picked up fuel and i can blow through the filter so idk if that was the problem so i got it started and now the one side is back firing and popping and that never happened before can it be my jets
 

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Discussion Starter · #10 ·
well guys just got in from from working on the xc heres the update i took the plugs out of the crankcase and the line and let a bunch of gas and s*&t out of it and i probably pulled it over 300 time gas coming out the line the plug hole of the crank and out my cyl because i had my pipes off also i put it all back together started it and ran on one cyl still shut it off changed plugs started on both cyl when hit the i am getting some crazy backfire i think it blew my ear drum what is causing that
 

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OK....breathe....it's usually a simple fix. Most likely, it's not your fuel pump or your filter. I doubt it's a crank seal issue because you probably would have burned it down by now. 98% of the time it's a clogged jet. Learn how to take the carbs apart and ESPECIALLY LEARN HOW TO REMOVE AND CLEAN YOUR PILOT JET. Don't ask someone who thinks they know how to clean the pilot jet ask someone who KNOWS. Pilot = low RPM. Needle (which rides on the main jet) = mid range. Main jet = wide open stuff. It is possible that there is gunk which is causing the needle/seat to stick. If your needle/seat is stuck this could cause it to load up and backfire. Forgive me if I'm telling you something you know!
 

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Discussion Starter · #12 ·
thanks for the reply i have cleaned them 20 times sometimes it just stop getting fuel on that one side..then others i have fuel then randomly i dont again will a plugged jet stop me from even getting fuel in the bowl
 

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Sounds like you have to clean the carbs. I just wrote this up in another recent post but it should help you.:

Do one carb at a time so you don't overwhelm yourself since the carbs might be a challenge if doing it for the first time.

1. The easiest way for you to take the carbs off will be to remove the air box, then unscrew the cap on top of the carb and pull the slide out and let it hang on top of the engine wrapped up gently in a rag making sure not to bend the long needle!

2. Then unscrew the choke from the carb by using 14mm and unscrewing it right off the carb.

3. Then obviously unscrew the thing that is clamped around the carb boot in between the carb boot and the engine so you can pull it.

4. Once you have the carb out, bring it to a workbench and take off the 4 screws on the bottom of the carb. This is the float bowl of the carb.

5. then unscrew the main jet and the pilot jet (http://www.teamcalamari.com/pix/24mm/6b.jpg)

6. Spray everything down with carb cleaner, including the jets.

7. Spray the carb cleaner in every hole you can find.

8. After, blow out all of the holes with compressed air.

9. After reinstalling the jets, you should be able to hold the carb up to a light bulb and see the light which should be unobstructed in a perfect circle.

10. Now you can put everything back together and move onto the next carb.

Some here may argue that you can't just blindly spray carb cleaner in everything and then blow everything out because you may miss a few things, but just give it a shot and see what happens. You really have to understand how a carb is designed to know how to clean everything out properly such as the pilot circuit or the choke circuit since these have 3 or more holes that are linked together. Let me know if I was unclear with anything or if you have any other questions.
 

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Discussion Starter · #14 ·
ok ill do it again tommorrow i have had these cleaned myself and the shop has done it. whats the best way to adjust the chokes i was told to drop them and pic them up an 1/8 of a turn so im getting full choke
 

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Another thing to rule out a dirty carb is just to swap carbs and see if the problem follows the carb.

Another thing with regard to the very good explanation about cleaning carbs is to clean the pilot you have to use a very small regular (slot) screwdriver to remove it -then take a small, stiff wire to clean all TEN holes....yes TEN.
 

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Discussion Starter · #17 ·
im heading right now to clean the carbs again...and for the gas in the crank im told im having needle and seat problems
 

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teamarctic14 said:
im heading right now to clean the carbs again...and for the gas in the crank im told im having needle and seat problems
In the bottom of the carb there are the floats. When that carb bowl is full, the floats rise up and push the fuel needle into the seat which blocks any more fuel from entering the carb. If you have a needle that is stuck, the flats may not be able to push the needle up far enough to block the fuel. This may cause the fuel to continue to flow and get into the cylinder. the only place the fuel has to go once it's in the cylinder is down around the rings into the bottom end. That may be one of your issues.

Here's an image to help you understand the different parts I am referring to in the following paragraph: http://ffracing.net/gallery/albums/Faded/floatlevel1.jpg
To check to see if the needles are good, there are a few things to check. One thing I like to do is when the carb is all apart, you can blow into the hole that he fuel line goes into. When the carb is right-side up, you should be able to blow into it, when it is upside-down, you should not be able to blow into it. You can also take them off and inspect the needle valves for wear. Also slide the needle into the seat, keep in mind that even the slightest rough spot can cause the needle to get stuck.
 

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Discussion Starter · #19 ·
i guess my carbs are bad i guess im told to look for new ones my crank is even filling right up with gas getting by the float
 
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