Boxerworks.com

Working on a friend's '75 R90s that has a leaking left side intake, pushrod seal.

Motor was rebuilt last year and new seals installed (by another technician).

I want to first try moving the ring on the tube to tighten the seal, but would like to use the proper tool. I don't see one on Ed Korn's site (cycleworks.net) so I'm looking for another source.

Or another idea?

thanks,

jimmyg

You can quickly cut one from a plumbing nipple, or white plastic pipe. Someone should attach a photo of one and you will see just how simple it is.

This was posted on the forum before:

viewtopic.php?f=1&t=6658

I was going to say that at some point, the rings were brazed to the tubes and pounding on them moves the whole tube and that creates a whole 'nuther set of problems. But in the linked thread, "Deleted User 62" says they were moveable until 1980, then brazed. But from another source, I read that they were brazed since the mid '70s. YMMV...

Kurt in S.A.

The R90S ring will move on the tube.

Kurt in S.A. wrote:This was posted on the forum before:

viewtopic.php?f=1&t=6658

I was going to say that at some point, the rings were brazed to the tubes and pounding on them moves the whole tube and that creates a whole 'nuther set of problems. But in the linked thread, "Deleted User 62" says they were moveable until 1980, then brazed. But from another source, I read that they were brazed since the mid '70s. YMMV...

Kurt in S.A.

That would have been Tim, cause I don't know that information.
As far as I know, we are the only two Deleted users that post here.

Yeah, I probably got that info from Snowbum.

Have you looked closely at the seal for any cracks/splits?

Thanks everyone for the thoughtful replies.

I'll try tapping on the ring and see what that does.

jimmyg

As you tap on the tool, watch the rubber donut carefully. It should just barely compress and the ring shouldn't pop back at all. If the donuts are only a year old, they should still be soft. If you wish to test them, sink your fingernail into it. If it is hard, it won't seal.

If you are doing this for the first time, it is kinda hard to see under there. Tilt the bike over on one cylinder and you will have good access and visibility. Just put a block of wood under the valve cover to protect it.

If I am being super simple, it isn't intended to offend you, but we have new readers that may not know some of the tricks.

thanks Duane,

I've worked on Airheads for 35 years and know my way around but your tips are solid, logical and I appreciate your time.

When I did the seals on my R90s in 2010, I remember using a Loctite type sealant (514 maybe?, but not threadlocker)

After cleaning the bores in the crankcase and tube ends, I applied sparingly to the seals.

No weeping at all in the last 5k miles. (FWIW).

jimmyg