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front sprocket leak

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:wall: much help needed. ive just finished my 199A and my front sprocket is leaking. so i changed the seal behind the front sprocket and the o ring and the metal bush. i replaced the sprocket and it was still leaking. it is leaking from the final end drive. so i replaced the seal on the end of the gear shaft. it is still leaking slightly but can you advise that this is normal for bultacos?

:wall: much help needed. ive just finished my 199A and my front sprocket is leaking. so i changed the seal behind the front sprocket and the o ring and the metal bush. i replaced the sprocket and it was still leaking. it is leaking from the final end drive. so i replaced the seal on the end of the gear shaft. it is still leaking slightly but can you advise that this is normal for bultacos?

Mmmh,

If you have installed the bearings right there should not come out any oil, Now there is only guessing left:

1.

The axis of the front sprocket spindle contains the shaft of the gear box and the clutch pressure rod / pin, like these russian puppets. May be you have something installed the wrong way from the inside?

2,

Maybe you have just filled in too much gear oil?

Where does the oil come out:

-a between the sprocket shaft and the oils seal

-b between the sprocket shaft and the inner shaft

-c from the hole of the clutch rod/pin?

Maybe this helps?

  • Author

hi thanks for your reply. feels like im going made. ive tryed about 4 seals now. the oil leak is comming from. between the seal and shaft. must say i may have put a wee bit to much oil in. but it wasnt alot more.also i didnt change the bearing. only the seal and o ring and bush behide the sprocket.

bondy -

You fixed this leak yet ?

A couple of thoughts - if it's leaking just standing, it points to incorrect assembly on your part.

On the other hand, if it only leaks after running or riding, it may be pressurising because the g/box breather is blocked - particularly if you've overfilled it with oil.

If you look at the left hand crankcase just above the boss for the kickstart shaft, you should see a small drilled hole - make sure this is clear.

Hope this helps.

  • Author

bondy -

You fixed this leak yet ?

A couple of thoughts - if it's leaking just standing, it points to incorrect assembly on your part.

On the other hand, if it only leaks after running or riding, it may be pressurising because the g/box breather is blocked - particularly if you've overfilled it with oil.

If you look at the left hand crankcase just above the boss for the kickstart shaft, you should see a small drilled hole - make sure this is clear.

Hope this helps.

hi mate no it dosent leak when standing. only when running. it dosent seem to be leaking as much. but dose still leak. i rang bultaco uk up.and they said i shouldnt have put 600ml in the gear box he says. it should only be 400ml ill have a look at what you said. and let you know how i get on. thanks for the addvice :thumbup:

  • Author

hi mate no it dosent leak when standing. only when running. it dosent seem to be leaking as much. but dose still leak. i rang bultaco uk up.and they said i shouldnt have put 600ml in the gear box he says. it should only be 400ml ill have a look at what you said. and let you know how i get on. thanks for the addvice :thumbup:

hi again yes you was right the gear box breather hole was block. with paint from when id painted the engin. i didnt even know there was a breather. so thanks for that. with abit of luck it might be ok now cheers :guinness:

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