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fuel screw/pilot screw??

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this is the same thing right?? in the manual it calls it a pilot jet in the OEM microfish it calls it set screw A and i now they sell a fuel mixture screw which is the same thing as the pilot jet right??

so starting from set or all the way down how many turns should i go out and the farther out it goes does what exactly to the bike ???

also how important is the washer and the spring that goes on this fuel/pilot jet mine did not come with one how bad is it not to run the spring and washer???

thanks for the help

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No the fuel screw and pilot jet are two different pieces. The pilot jet is inside the carb. The Fuel screw is accesable from outside and under the carb. They are related though, If your fuel screw doesn't get the bike tuned properly, your pilot jet size is wrong. But if your bike is stock it should be fine with the stock pilot jet.

The spring, washer and o-ring are on your stock screw. If it didn't come out with the screw put the screw back in, run it all the way in and then out, the parts should come out. Then transfer them to your new fuel screw. You need them or your screw will fall out. Didn't you read the instructions that came with the screw? They are basicly what I just posted.

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No the fuel screw and pilot jet are two different pieces. The pilot jet is inside the carb. The Fuel screw is accesable from outside and under the carb. They are related though, If your fuel screw doesn't get the bike tuned properly, your pilot jet size is wrong. But if your bike is stock it should be fine with the stock pilot jet.

The spring, washer and o-ring are on your stock screw. If it didn't come out with the screw put the screw back in, run it all the way in and then out, the parts should come out. Then transfer them to your new fuel screw. You need them or your screw will fall out. Didn't you read the instructions that came with the screw? They are basicly what I just posted.

What he said. :ride:

For your air fuel mixture screw, the spring, washer, and o-ring are very important. also make sure they are stacked in the right order. If you don't see them, then cj-s4 is right they may be stuck inside the A/F port(channel) I have had to use a dental pick to get them out. Let us know how it goes. :thumbsup:

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thanks they are not stuck i pulled the o ring out but no spring or washer i did not buy a new fuel screw i wa cleaning my carb out when i found the missing parts and as far as i can see the pilot screw is the same thing as the fuel screw they both come out side the carb at least that is the only screw on my manual that has a oring washer and spring

i have ran this bike about 2-3 hours since i bought it and it never had a fuel screw washer or spring how bad is that as well as it was backed out 5-6 full turns when i took the carb apart under the rubber fuel pump it was all auxodated and rusty color what is going on is this bad???

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check out items:

number 8 ( air fuel mixture screw) ADJUSTABLE (TURN OUT 1.5 - 2.0 TURNS OUT)

number 42 or 45 are the slow speed, or starter jets. they are not adjustable, only replacable with different oriface diameter.

hope this helps

2374_CARBURETOR.gif

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Can you tell me the Honda part number for that fuel screw O ring? # 2 in the diagram? Need it quick for a WR Yamaha, and Yamaha only sells the whole fuel screw and I don't have time to order it separately from Sudco.com.

BTW, for anyone good on jetting or modern 4 strokes, I recently started getting a horrible high rpm misfire, (about 10k, I guess, btw- I am not hitting the rev limiter, that is about 13,500 on the 250). It happens in neutral or with the clutch in while in gear easily, but not as easily, under the load of the bike while riding, where it does not rev as easily, but still starts a misfire just as you are thinking about shifting. The bike starts and runs perfectly, except for this misfire. I tried a new plug, checked all electrical connections, tested my TPS (and removed it with no improvement), went leaner on the main jet and clip (thinking it was rich on top, even though it has ran fine all year with the current JD jet kit) and cleaned the carb. When I removed the fuel screw, I found the O ring tore in half, so I tried to run without it, but still have that darn miss. Now, I know the fuel screw is for low end and part throttle applications, but could having that O ring gone completely be causing my high rpm misfire? That is the question!!! Thanks alot, Randy

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