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Loose main jet on 645b kehin carb..

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Quick question for you all... I've got a 72 honda xl 250. As you can imagine the carb is quite oldLOL In taking it apart to clean it I took the main jet out, and now it wont go back in and stay. Im sure i don't have the terminology right but the main jet looks like a small plug. It has what looks to be a plastic sleeve around it that holds it in place...its partly cracked. Anyone have a fix for this? Other than a new jet?

It may sound a little farfetched (i.e. stupid), but i was thinking of a little form-a-gasket to keep it in place but im unsure if thats a good idea for the innards for a carb...

Any suggestions? I'm kinda getting desperate here...

Maxx

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its held in by a oring and a bracket that the float bowl pushes against.

Oh.....DUH :thumbsup:

Yeah I went back and took a look at ALL the parts and now i see it. I guess thats what happens when you look at all the small bits and not everything together. Thanks for clearing things up.

So, is this one of the ten stupidest questions asked here? I really am smarter than this I swear...

One question.. What happens if the o ring is old and not sealing perfectly?

Off to play with gasoline and matches...

M

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they will run super rich becuase fule is being pulled around the main jet instead of thru it.

Ugh, thats not good. Is there any way to fix it without buying a new o ring? I'm not even sure they even SELL a new o ring for a carb this old...

M

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you need a new oring.

a good hard ware store should have the right oring.

Well, I put the carb back together and tried it without the o ring. Not that i dont think your not right, it just wont be for another weeks until i can get to a decent hardware storeLOL I live 70 miles out from a good storeLOL

Somewhere in the rebuild i fixed one of the problems. It starts on the second kick and i can rev it freely without it dying. Now it seems to be running rich (and i was hoping to get luckyLOL) and idling VERY fast. This im guessing is from the lack of decent sealing from the o ring. Its also blowing out a LOT of blue smoke and some oil out the tail pipe and where the exhaust connects to the engine. Is that from the running rich as well? I hope???

M

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try turning the idle speed down.you definately need the oriing,but sounds like the motor has some issues.

I did and it helped a little...but still seems rich and idling fast. I took it for a test ride and first gear was twice as fast as it was before i did the carb. I had to ride the breakLOL

I was told it could be worn valve guides, but the guy who told me that was later fired for incompetance. So, I was hoping..LOL

Anyway, thanks for your help! I'll get the o ring and do a little more research on engines. Maybe post to the engine section and see what hey think as well...

Again, thank you!

M

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