Jump to content

B12 broken oil pump gear - why?how?


FJD

Recommended Posts

Posted (edited)

story so far: i´ve sold ths perfectly working B12 few weeks ago.

Today he calls to tell me he wanted to have the clutch being replaced by some mechanic.

Before getting there from his words there was a "bang" on the traffic lights, and then he pushed the bike to his mechanic (which i do not know if he is a pro, or just some friend of the Bandit Buyer).

My question: what could have possibly gone wrong ?

Or do they want to fu... with me, because the mechanic screwd up while doing the clutch ?

Maybe impact wrench - failure ?

I don´t want to be unfair, but this bike worked very well all the time i had it, never had any problems at all.

Edited by FJD
Posted (edited)

They only normaly break if you don't get the teeth lined up when assembling it..."So Ham Fisted mate by the look"

tell him to do one

PS I would toss back why does it have a different clutch cover gasket now ? It had a cometic one  on it when I sold you it line 9_9

 

Edited by Duckndive
Posted

i have a half torn apart b12 engine in my workshop with a blown oil pump (it´s cracked), and i do not recall it to have broken teeths.

I do not know what caused it to crack, as i´ve bought that engine stuck as it was

Posted
7 minutes ago, Duckndive said:

They only normaly break if you don't get the teeth lined up when assembling it..."So Ham Fisted mate by the look"

tell him to do one

PS I would toss back why does it have a different clutch cover gasket now ? It had a cometic one  on it when I sold you it line 9_9

 

what i wanted to hear....but there are a few teeth broken, some in between are good again - that´s funny somehow ?!

just misaligning would only break a few, just the ones in contact i think

Posted
11 minutes ago, FJD said:

what i wanted to hear....but there are a few teeth broken, some in between are good again - that´s funny somehow ?!

just misaligning would only break a few, just the ones in contact i think

yes but if he then started it up as they had not noticed the #uc# up ...Bang more teeth......looking at the gear on the back of the clutch basket would help / show the full damage...

 

Posted

Looks like the classic clutch basket removal and not re fitting it properly, :) if the drive gear for the pump and alternator arent meshed before tightening the clutch hub, it will break the oil pump teeth, have a look at the alternator drive gear  and see if thy are bust as well.:tu

never known a pump to fail and jam..:|

Posted

So boils down to 2 poss mistakes:

A) Oil pump stuck

B) mechanic's bodgery/misaligning

 

If i take out the clutch, and cannot rotate the oilpump by hand it's A i guess ?

Posted (edited)

i just dismantled the clutch on the B12 lump with cracked oil pump i had lying around, and one more possible reason crossed my mind:

no clutch holding tool combined with an air gun/impact driver could have broken the teeth, as the crank won´t be able to rotate backwards becaus of starter sprag clutch.

Im definitly sure, it could not happen during running engine, and i do not think the oil pump is stuck.

Also talked it over with my uncle, who´s a very good self teached engine builder (runs a 600hp Superstreetbike Kwaker turbo), and he has come to the same conclusion.

Tomorrow evening i will drive to this guy, take out the clutch, and see if the oil pump spins or not.

Edited by FJD
  • Like 1
Posted

Soo...he has a brand new clutch, a hand -rotatable oil pump, and a lot of missing tooths on both gear wheels.

Told him point blank that the failure was up to the one who changed the clutch.

  • Like 4
Posted

What's the betting the mechnik almost got it right and just cracked one or two of the teeth, then after completing the work , he hit the starter and .......... carnage resulted. Those little starters have so much torque, a damaged pump gear don't stand a chance - expensive mistake!

  • Like 1

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...