The member photo gallery is now integrated and live!!  All user albums and pictures have been ported from old gallery.


To register send an e-mail to admin@bmwr65.org and provide your location and desired user name.

Author Topic: Cylinder removal - opinions?  (Read 707 times)

guitardad

  • Guest
Cylinder removal - opinions?
« on: December 02, 2007, 07:42:00 PM »
I've reached the point in Project Hans where it's time to replace the pushrod tube seals.  These are a pretty common source of oil leaks, and Hans' are definitely leaking.  But - that means removing the cylinders.  I've heard two schools of thought:

1. Pull the cylinder out until the piston skirt is out, so you can reach the wrist pin.  Then push the pin out, leaving the piston in the cylinder.  This way the rings are still in the cylinder and don't have to be compressed to reinstall the piston.

2.  Pull the cylinder completely off the piston.  That way the wrist pin doesn't have to move, and you can make sure the gaps in the rings don't line up.

So which do you prefer?  And why?

Offline Justin B.

  • Administrator
  • Mt. Olympus Resident
  • *****
  • Posts: 5983
  • I love my Beemers
Re: Cylinder removal - opinions?
« Reply #1 on: December 02, 2007, 10:34:47 PM »
I pull the jug off, that way I can de-carbon the top of the piston, inspect the lifters, and inspect the bore.  Some write that it matters not to de-carbonize but something just "feels" wrong if I put it back together dirty!  The rings are easy to squeeze together with your fingers and don't worry about having the gaps 120 degrees (or whatever) apart as rings rotate anyway, right?  I don't line them up right on top of each other but probably 30 degrees or so and I've never had any problems.

Oh, this is what a 78k mile lifter can look at, the others were fine:
Justin B.

2004 BMW R1150RT
1981 R100RT - Summer bike, NEKKID!!!

Offline Semper Gumby

  • Mt. Olympus Resident
  • ****
  • Posts: 2173
  • Dances with cow!
Re: Cylinder removal - opinions?
« Reply #2 on: December 04, 2007, 07:43:02 AM »
One other suggestion is to tap the rings down that hold the push seals against the crankcase.  Then either spot weld or put a hose clamp behind the ring so it doesn't slide up the tube again.  Call Nathan at Boxerwors to find out how much as he did this for mine on the top rebuild and they don't leak anymore.  Now about that darn $33 neutral switch..... >:(
Bill Gould ?1980/03 R65 When at first you don't succeed....Moo!

thrang

  • Guest
Re: Cylinder removal - opinions?
« Reply #3 on: December 06, 2007, 07:51:00 AM »
Since pulling the barel off is not something that you hve to do that often I just pull them off the bike.  That way I can inspect the nicasil liners inspect the rings and piston bodys before giving the piston crowns a clean and and check for any damage or heat scoring.

Although a few have mentioned leaking push rod tube seals, its not something I've ever had that much trouble with. I just make sure that the holes are nice and clean, and replace them the seals when ever I have had the barels off. wh bothe reusing the old seals when replacements aren't that dear?