Author Topic: engine breather (again)  (Read 1768 times)

Offline KeithJ

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Re: engine breather (again)
« Reply #30 on: 30.11. 2016 22:24 »
Just looked at a breather and it has two holes in it 180 deg apart.  So it "vents" every revolution.

AtB

Keith
'59 A10RR + Second engine

Offline duTch

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Re: engine breather (again)
« Reply #31 on: 30.11. 2016 22:38 »

 Yep, as it needs to
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Online KiwiGF

  • Last had an A10 in 1976, in 2011 it was time for my 2nd one. It was the project from HELL (but I learned a lot....)
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Re: engine breather (again)
« Reply #32 on: 01.12. 2016 02:21 »
Hi
Quote
The clearance between the breather and the inner timing cover would also impact the vacuum

When the case is bolted up and compresses the cork washer there is zero clearance between the breather flange and inner case !

Kiwi,
If the case was bolted up without aligning the peg and breather it may have damaged the case ???
Worse if it was run like that, or with a too tight preload and worn the alloy case ????

John

There was no evidence of wear on the case, but it's difficult to tell, there was evidence of the peg wearing the breather, but nothing too serious so I guess the peg wore away pretty quickly. The bike was a basket case pretty much when I got it and I never ran it like that, I noticed the problem when building the engine up.
New Zealand

1956 A10 Golden Flash (1st finished project)

1949 B31 rigid “400cc hot rod” (2nd finished project, + favourite bike)

1949 C11 rigid, but why!!! (cos it was cheap)

1937 B21, project missing parts, mission impossible?

GL1800 Goldwing, well, the wife likes it

KTM 950 ADV, cos it’s 100% nuts

1952 Armstrong Siddeley Whitley for rainy days (with wife

Offline duTch

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Re: engine breather (again)
« Reply #33 on: 01.12. 2016 03:20 »
 
Quote
Its an urban myth.
Has anyone actually seen with their own eyes that replacing the cork washer fixes oil coming out the breather?

  This may well be a mighty fine opportunity to find out...."suck 'n See" *smile*

 I'm not sure if I needed to actually do it, but at least considered packing a too-thin cork with gasket paper behind (sneaking suspicion I did)
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Online RichardL

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Re: engine breather (again)
« Reply #34 on: 01.12. 2016 06:34 »
Uuuuugh! It's been a long time since I looked at that damn breather and have embarrassed myself again. So, anyone care to comment on my claim of neutral pressure versus tuning for pressure? I may as well have a thorough stropping, no reason to go half way.  Next time I'm just claiming old age and leaving it at that.

Richard L.
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020 (if it's not cancelled and we are free to move about by then). Watch website at https://www.gentlemansride.com for details.

Offline KeithJ

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Re: engine breather (again)
« Reply #35 on: 01.12. 2016 08:37 »
Doesn't the cork washer also cut take out the end float on the cam shaft?  Or have I misremembered?
ATB
K
'59 A10RR + Second engine

Offline duTch

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Re: engine breather (again)
« Reply #36 on: 01.12. 2016 09:01 »

 
Quote
Doesn't the cork washer also cut take out the end float on the cam shaft?........

 Emphatically NOT... *bash*

Quote
  Or have I misremembered?
     Yep

 Set the Cam end float independently, and when I did mine, I put the barrels on blank (no lifters/followers/"tappets") and look down the pushrod tunnel to check for centrality.
 Then do the other thing whatever we're on about
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia