As my airhead gently weeps

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Wobbly
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Re: As my airhead gently weeps

Post by Wobbly » Thu Sep 21, 2017 11:25 am

richard t wrote:
Wed Sep 20, 2017 9:41 pm
On the /6's the ring on the push rod tube is movable, I have a tool to tighten it against the seal, some times it will stop the leak until you get time to change the seal. If the rubber is rock hard you gonna have to change the seal.
I agree. On the /6 and /7 machines I'm familiar with, the chrome push rod tube is pressed into the cylinder. The push rod seal is a large block of synthetic "rubber" which, through the material quality of being "springy", works by pushing against both the tube and the engine case, thereby effecting an oil-tight seal.

As these seals naturally age harden due to heat, soap, UV, etc, their springiness starts to wane. The drift shown is typically a homemade tool that allows the push rod tube to be driven out of the cylinder 1 or 2mm to restore the seal's tight fit with the engine case.

It's a temporary measure, since the real culprit is the hardened push rod tube seal. But I agree... if the engine is running really good... then don't mess with it. Do the rings, seals, and valves all at one time. Much better to 'kill 2 birds with 1 stone.'

The top end job is expensive, but the real BMW parts are worth the price. The wise thing to do is to start stockpiling gaskets and seals over the next few months, so that you don't have the full expense at that future date. ;)
After 20 years as a professional bike mechanic and 30 years as an engineer I know just enough to be dangerous !

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Zombie Master
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Re: As my airhead gently weeps

Post by Zombie Master » Thu Sep 21, 2017 12:57 pm

I've got all the gaskets for a top end re-seal, though I bought them from Moto Bins and am a bit concerned that they might not be the best parts to install. I had a terrible time with their caliper re-build kits, and ended up having to buy an OEM kit that went in with no problem. Turned out that I didn't need to rebuild the calipers anyway:(
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Rob
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Re: As my airhead gently weeps

Post by Rob » Thu Sep 21, 2017 2:18 pm

So, I guess that we in the USA are blessed that Moto Bins does not ship here?
Rob V

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George Ryals
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Re: As my airhead gently weeps

Post by George Ryals » Thu Sep 21, 2017 5:24 pm

I bet it is the oil pressure switch!
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'74 R90S, '67 /2 Conv w/sc, '66 R50/2
'74 Harley FXE, '72 Harley FLH w/HD sc
'69 BSA 441 Victor Special, '74 R90/6 Basket case
'85 R80RT wreck for parts

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Zombie Master
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Re: As my airhead gently weeps

Post by Zombie Master » Thu Sep 21, 2017 7:15 pm

George Ryals wrote:
Thu Sep 21, 2017 5:24 pm
I bet it is the oil pressure switch!
I'll check that out...thanx!

Can I pull off that switch when the bike is full of oil. How is the switch sealed?
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melville
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Re: As my airhead gently weeps

Post by melville » Thu Sep 21, 2017 11:42 pm

Zombie Master wrote:
Thu Sep 21, 2017 7:15 pm
George Ryals wrote:
Thu Sep 21, 2017 5:24 pm
I bet it is the oil pressure switch!
I'll check that out...thanx!

Can I pull off that switch when the bike is full of oil. How is the switch sealed?
Yes, you can pull it off when the sump is full. The switch is on an oil galley above sump level.

My /6 had a crush washer and straight threads on the switch. Some might have pipe (tapered) threads like an ACVW.
Call me Mel. Some years ago- never mind how long precisely- having little or no money in my purse, and nothing particular to interest me at home, I thought I would ride about a little and see the other parts of the world.

richard t
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Re: As my airhead gently weeps

Post by richard t » Fri Sep 22, 2017 1:01 am

you are right, only works on the older bikes. Airbear's picture looks right. Mine has a numbers on it.

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Zombie Master
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Re: As my airhead gently weeps

Post by Zombie Master » Fri Sep 22, 2017 4:34 am

Thanx Mel! I'll do some checking to see if that switch is leaking. I've got a long 24mm impact socket. Anybody know what size gasket would be on that switch?
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SteveD
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Re: As my airhead gently weeps

Post by SteveD » Fri Sep 22, 2017 7:31 am

Rob wrote:
Thu Sep 21, 2017 2:18 pm
So, I guess that we in the USA are blessed that Moto Bins does not ship here?
That'd be Motorworks Rob.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/
2006 K1200R.

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SteveD
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Re: As my airhead gently weeps

Post by SteveD » Fri Sep 22, 2017 7:32 am

Rob wrote:
Thu Sep 21, 2017 2:18 pm
So, I guess that we in the USA are blessed that Moto Bins does not ship here?
That'd be Motorworks Rob.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/
2006 K1200R.

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