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Oohh Err Missus!!!


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Hobbit210

 
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Oohh Err Missus!!!

Wed Jan 11, 2012 11:00 pm » Post: #1 » Download Post

Started stripping down Noodle to check crank seals etc etc to find out why it was such a 'dog' to start. Well I think that I found out why..see below...



The little four way plastic joiner was broken. I have carefully super glued it then I've built uop a layer of Araldite around the break. Should (?) be okay. If not, are they available to buy?





Then I removed the carbs and look what I found......One of the crank halves (1/4's) has heavy rust pitting on it. Has anyone seen anything like this before?




Help please!

Mike
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Lesviffer750
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Wed Jan 11, 2012 11:23 pm » Post: #2 » Download Post

Jesus Mike, cant believe what im seeing, ill look see if i have a spare plastic cross piece.
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Lesviffer750
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Wed Jan 11, 2012 11:29 pm » Post: #3 » Download Post

David Silver has the plastic cross piece, special order £13.22, ill check in the morning if i have one.
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Hobbit210

 
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Thu Jan 12, 2012 8:35 am » Post: #4 » Download Post

Thanks Les, do you have his number?

I've never seen rust quite like this before, it appears to be quite thick.

Plus points: More crankcase compression (on one cylinder)
Negative points: Out of balance crank...... Wel you got to laugh Crying or Very sad
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Lesviffer750
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Thu Jan 12, 2012 9:27 am » Post: #5 » Download Post

PM sent Mike.
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Hobbit210

 
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Thu Jan 12, 2012 11:06 am » Post: #6 » Download Post

Thanks Les. PM sent

I have my own ideas about this and this is why I wondered if 'anyone' had come across anything like this before. The crank was 'supposedly' new in 2004, I've got the reciept for it BUT is it posible that the crank might have been a 're-build' as this rusting only appears on this one crank halve. If there had been moisture in the crankcase (?) then surely it would have effected both halves. The rusting is all around the periphery so, in my opinion, that cancels that theory out anyway.
The rest of the motor, so far, looks superb.

Mike
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Hobbit210

 
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Thu Jan 12, 2012 4:29 pm » Post: #7 » Download Post

...Anyone?
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Dave Ett
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Thu Jan 12, 2012 7:46 pm » Post: #8 » Download Post

Very strange! Mine has never looked like that, and it has stood in a garage for several periods of it's life...
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Hobbit210

 
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Thu Jan 12, 2012 10:22 pm » Post: #9 » Download Post

Of course. I don't think that it is caused by 'sitting around'. I feel sure that the company that originally put the 'New Crank' in it were not, maybe, totally conversant with the word NEW! The other half of the web on that cylinder is completely spotless...it even looks like different metal...but maybe I'm just being paranoid now!
Is it possible to just get one part of the crank replaced?
It might be that I'm able to clean it off when I get the crank out?

Mike
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Harryredchow

 
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Fri Jan 13, 2012 9:07 am » Post: #10 » Download Post

Could be that the bottom cylinder gasket (front or rear) has been leaking coolant into the crank case. Would certainly explain the rust.
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Lesviffer750
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Fri Jan 13, 2012 10:07 am » Post: #11 » Download Post

I think you have stumbled on the answer Mike, yes you can split the crank, and yes, that company probably did'nt know what the word new meant. Having said that, their should'nt be any problems, clean it up put some new seals in while you have it apart and it should be good to go. At least we know where not to go in the future.
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Hobbit210

 
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Fri Jan 13, 2012 4:00 pm » Post: #12 » Download Post

Thanks Les. I should get time on Sunday to remove the crank and take a closer look.

I'll keep you informed.
Mike
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Hobbit210

 
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Mon Jan 16, 2012 11:32 pm » Post: #13 » Download Post

Got the crank out tonight to look at the rust situation.

It's not as bad as I thought, I have cleaned it up but it has left the crank a bit pitted. Do any of the 'guru's' out there think that it will be ok?

Just to chec k the crank, I put it between centres on the lathe and there was only a small amount of 'throw-out' Don't laugh, I can't really read the meter but I remember from when I used to do my kart (single cylinder) cranks what was the allowable amount of movement. It's well within that spec! Not bad for a twin I thought!

Before:


After:



Do you think that I should try to clean the crank web up more. I didn't want to start removing metal.

Also, the bearing on the clutch side is well, dry! It's in good nick but it doesn't look 'well oiled' if you see what I mean.

Mike
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Hobbit210

 
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Tue Jan 17, 2012 7:59 am » Post: #14 » Download Post

One thing that I didn't mention, and I don't think that you can see from my 'phone' pics, is that the crank is quite 'blued' around the big end pin on rusty web.

Mike
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nobby62
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Tue Jan 17, 2012 12:29 pm » Post: #15 » Download Post

Hobbit210 wrote:One thing that I didn't mention, and I don't think that you can see from my 'phone' pics, is that the crank is quite 'blued' around the big end pin on rusty web.

Mike


My crank is out at the moment and it is also "blued" around the crank pin... There's no sign of any damage though, so I suspect its quite normal.....?
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