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JJH
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push rod tube seal hell
05/28/17 at 19:41:09
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1979 BMW R65
I am trying to replace my push rod tube seals.  First time removed carbon from piston and head, honed (not bored) cylinder, new rings, new gaskets and new o-rings.  The bike ran fine I rode it for a few hundred miles, but it was still leaking from the new  tube seals.  The seals where pointed down, head and cylinder properly torqued.  Spent some time looking around the internet, and found some advice to put a small smear of RTV on the seals.  So I pulled the cylinder/head (I kept the heads attached).  Cleaned the cylinder/ block surface and put a small smear of RTV on the push rod tube seals.  Put it back together, now the seals are leaking very badly on one side.  When I pulled everything the second time I did not use new anything, just put a light smear of RTV on the tube seals.  My next step is just to start over with new push rod tube seals and a thin smear of RTV.  I did notice when I pulled the cylinder the second time the tube seals were slightly indented.  I am thinking this was most likely the cause.

So...
1.  I am putting in new tube seals.
2.  Should I put in new cylinder o-rings and the little stud o-rings?
3.  Any reason to take off the head/ new head gasket?
4.  Any reason to put a light hone on the cylinder before putting the piston back in?

Thanks,
John
  
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Bob_Roller
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Re: push rod tube seal hell
Reply #1 - 05/28/17 at 19:47:26
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There are lines molded into the upper surface of the    pushrod seals, believe that the lines should be orientated towards the engine case .

Other possibility, is that the stops, or washers on the pushrod tubes may have moved up the tubes, so you are not getting a good seal on the pushrod tube seals .

If this is the case you can try tapping on them with a suitable tool to push them back down .
  

'81 R65
'82 R65 LS  
'84 R65 LS
'87 Moto Guzzi V65 Lario
'02 R1150R
Riding all year long since 1993 .
I'll give up my R65, when they pry my cold dead hands from the handlebars !!!!!
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JJH
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Re: push rod tube seal hell
Reply #2 - 05/28/17 at 20:56:47
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Bob, thanks for the reply.  I am pretty since the tube seals were indented and did not go in the exact same place, hence the large leak. I did not even start the engine (I changed the oil so was turning the engine over without starting) and I saw that the tube seals were leaking badly.  I am close to crying! Cry
  
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Bob_Roller
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Re: push rod tube seal hell
Reply #3 - 05/28/17 at 23:13:33
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OK, I was at work today had the Guzzi, when I got home I looked at one of the R65's, the molded line, is supposed to be located at the 12 o'clock position, towards the cylinder .
  

'81 R65
'82 R65 LS  
'84 R65 LS
'87 Moto Guzzi V65 Lario
'02 R1150R
Riding all year long since 1993 .
I'll give up my R65, when they pry my cold dead hands from the handlebars !!!!!
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JJH
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Re: push rod tube seal- again!
Reply #4 - 06/06/17 at 09:27:44
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1979 R65.  I need to know the proper orientation of the pushrod tube seals.  There is a "fat" side and a "skinny" side.  Which side goes down, which side goes up?  In looking online the fat side appears to go down, but is this correct?  When I tried to fit them it did not seem to want to fit this way.  If any of you have the time can you look down and see how your seals are oriented.  Thanks,

John
  
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Barry
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Re: push rod tube seal hell
Reply #5 - 06/06/17 at 15:35:13
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Hard to judge from installed seals because the pushrod tube collar is in the way but given the pushrod tubes enter the crankcase from an upwards inclination they must fit fat side downwards.
  

Barry Cheshire, England 79 R45
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JJH
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Re: push rod tube seal hell
Reply #6 - 06/06/17 at 16:10:36
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Barry thanks for the reply.  I am having a really tough time replacing these seals.  They seamed to deform the first time I placed them.  The second time I placed RTV sealant on them, and the leaked.  I pulled them again, thinking maybe they are in the wrong way, hence the question.

John
  
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Bob_Roller
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Re: push rod tube seal hell
Reply #7 - 06/06/17 at 19:02:48
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Remove one pushrod tube seal, look at the top of it, there should be a line molded into the rubber, that line is to be at the 12 o'clock position on the pushrod tube .
  

'81 R65
'82 R65 LS  
'84 R65 LS
'87 Moto Guzzi V65 Lario
'02 R1150R
Riding all year long since 1993 .
I'll give up my R65, when they pry my cold dead hands from the handlebars !!!!!
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JJH
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Re: push rod tube seal hell
Reply #8 - 06/06/17 at 19:24:26
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Bob, thanks for your reply!  Your earlier reply about the line at 12 is the reason for my question.  On the tube seal the line is on the skinny side (see photo).  So at 12 that would put the "fat" side down.  It seem to "fit" better with the skinny side down.  I am trying not to force anything, but I will admit I am pretty frustrated.  In other online references I have read about the line being at 6.  So I am trying to get away from the line and just trying to find out "fat or skinny" down.

Best regards,
John
  

r65_pushrod_tube_seal.jpg ( 28 KB | Downloads )
r65_pushrod_tube_seal.jpg
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Bob_Roller
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Re: push rod tube seal hell
Reply #9 - 06/06/17 at 19:35:32
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Remove a seal and place it in the hole in the engine case and see where it fits .

Also, you don't need any sealant on the seal, just lube it up with engine oil .
  

'81 R65
'82 R65 LS  
'84 R65 LS
'87 Moto Guzzi V65 Lario
'02 R1150R
Riding all year long since 1993 .
I'll give up my R65, when they pry my cold dead hands from the handlebars !!!!!
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JJH
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Re: push rod tube seal hell
Reply #10 - 06/06/17 at 21:45:46
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Bob,  thanks for your help.  I have the seals in place.  They seem "happy".  Once I get the rest reinstalled and adjusted I will give the board an update.  Thanks again.

John
  
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Bob_Roller
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Re: push rod tube seal hell
Reply #11 - 06/09/17 at 18:01:24
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Great you got it figured out !!

My first time with these seals wasn't a pleasant experience, I contacted a co-worker that had worked on airheads for decades clued me in on what to do .
  

'81 R65
'82 R65 LS  
'84 R65 LS
'87 Moto Guzzi V65 Lario
'02 R1150R
Riding all year long since 1993 .
I'll give up my R65, when they pry my cold dead hands from the handlebars !!!!!
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Re: push rod tube seal hell
Reply #12 - 06/10/17 at 00:10:09
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I think snowbum's advice is also to put new engine oil on the outside of the seals, and use some silicone grease on the inside so it is easier to turn them around to line them up when installing them and just prior to tightening the head nuts.   I've followed this advice with good results on my airheads.. though, my R100's "collars" were loose and kept sliding up out of position (by a large amount) and wouldn't hold any compression against the rubber seals -> continual leaks reappearing..  I ended up putting the collars into the proper position on the push rode tubes and silver-soldering them into place with some plumber's flux and a blowtorch. 
  

Airhead #12178   BMWMOA #123173  BMWRA #33525  GSBMWR #563  1982 BMW R65LS  1978 BMW R100/7 1998 Kawasaki Concours
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Aethelric
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Re: push rod tube seal hell
Reply #13 - 12/02/18 at 08:39:37
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Did we ever resolve if the seal should be installed fat side up or down.  I'm currently re-building mine and it seems that the fat side goes up and the line as mentioned is at 6 o clock. I can't really get it to fit the other way. 
  
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Re: push rod tube seal hell
Reply #14 - 12/02/18 at 17:57:19
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