#@%^#* Fork Seal

[beby99]

What the heck...A few years ago I replaced my leaking fork seals. Well now one of them sprung a leak so I replaced it with a OEM seal and now that one is leaking worse than the aftermarket I just took off.

Do these seals have an downside or upside (maybe it's upside down).
It has like a 45 deg. angle cut around one end and flat on the other. I put the 45 deg. faceing down into the fork.

I did not replace the friction metals as they looked ok and the fork tube has NO pits or blemishes. Any ideas ya'all?

[Clone]

Yes, they do have an up and down. My memory doesn't serve me too well, but the tighter of the spring wipers goes down.

[tfb]

Sounds like you put them in the right way around.

1. Are you SURE there are no small nicks etc. on the fork tubes? Take some emery paper and deal with any nicks -- even tiny ones -- that you find.
2. Never mind if the bushes (= "friction metals") didn't look worn. The important question is, how much side-to-side freeplay is there in the unit? This needs to be examined before you put the seals in. If it is excessive, then it will cause premature failure of any seals you put in.

Now, if the freeplay seems excessive (and I think there are some figures quoted in the manuals; I would have to check) and the bushes aren't apparently worn, it will mean that the insides of your fork lowers are worn... and there's nothing you can do about that...

... EXCEPT, perhaps, inserting a sliver of thin metal sheet behind each bush to tighten things up a tad. :-| ... either that, or replacing them.

[beby99]

No...I'm SURE there's no nicks. I checked and double checked as I thought this was the problem...smooth as a baby's butt.

I guess I will try new bushings as there cheap and still available but I would wonder why the other fork/side is not having any problems. You would think that the bushings would where evenly on both sides?

Thanks for the info guys.

[tfb]

smooth as a baby's butt

Well that's a good thing!

As to why it's one side and not the other... hmm, if it's the worn bushings and/or fork lowers allowing too much lateral freeplay in the whole plot, it could be that in a week or two the other seal will burst too.

Of course I'm just speculating here, but honestly these are the only two normal causes of seals leaking that I know of: 1. worn fork internals, and 2. nicks in the fork tubes.

If anyone out there knows of other causes, please chime in with your wisdom!

[mdole]

It's actually pretty easy to damage the seal while sliding them down over the fork tubes. I damaged a number that way that had me redoing them a little later.

Now when I'm putting the new seal on I first put a small piece of plastic wrap over the top of the fork tube about 6 inch x 6 inch, coat the inside of the seal with cup grease (heavy coat) then carefully start the seal down over the plastic wrap, poke a hole in the p[lastic wrap to let it slide down the fork tube, grap an overlap the seal with the plastic wrap that is still below it and slide the seal down to close to the lower fork tube the pull the plastic wrap out and start the seal down into the lower fork tube. Then I slide the old fork seal down and use a hard plastic mallet to tap the seal into place. I use the old fork seal as a driver.

I haven't had a new seal mess up since I started doing it this way. On the few leaky seals that I looked at I could see fine cuts on the lips of the seal.

Good luck.

[beby99]

Thanks for the tip mdole....I have heard of using a piece of plastic from a milk jug to rap around the tube and then slide seal over it thus sliding the plastic down the tube instead of the seal. I however did NOT do this as my fork tube looked fine.....maybe not? I'll try this method as well as replaceing the bushings.