Fork Seals

[jamiewalp]

Hello, new to the site. I own a 1100SF 1979 and am finally doing a much needed overhaul. So far so good but have ran into a problem with the fork oil seals.
The seals in the forks do not correspond to either tech manuals I own. I know the bike has never been touched by anyone but my dad or myself. A large seal like the manual and yamaha shows and under that a second smaller seal, kind of like a o-ring encased in a metal c channel. These were both on top of the washer as described in the manual. Does ANYONE know if I need to replace this or where to find it. Yamaha says it doesnt exsist. ANY help greatly appreciated. Jamie

[prometheus578]

If I understand you correctly.....
The "Large Seal"(can be seen on the outside of the forks) is the dust seal. The inner seal is the actual fork oil seal. That is the one you'd replace.

[jamiewalp]

Fork seals, again

Dont think its the dust seal, but if it is, does anyone know the correct Yamaha part #s for the dust seal and oil seal as Yamaha doesn't list them for a '79 1100SF. Thanks Jamie

[Jerry]

The following are part numbers:

Item 4: 3h3-23146-00-00 Seal, Spacer
Item 5: 3h3-23145-00-00 Oil Seal
Item 6: 1J3-23156-00-00 Stopper Ring, Oil Seal
Item 7: 1J3-23166-00-00 Piece, Oil Lock
Item 8: 383-23135-00-00 Metal, Slide

Item 14: 3h3-23144-00-00 Dust Seal

Don't know exactly what parts you need, but this is the official Yamaha microfiche for a '79 SF fork. If the parts you have are not in the microfice I'ld rebuilt it to match the 'fiche.

Yamaha does list them, sounds like your dealer doesn't want to be bothered. This photo is from the on-line Yamaha parts catalog which you can find at:

Yamaha Parts Catalog

[Jerry]

Fat fingers...item 8 should be 3H3, not 383...

[jamiewalp]

Thanks guys for the help.

[tony7914]

Hi there,
I have a question concerning replacing fork seals. Hows the best way to do it at home and what tool do I need to buy to seat the seal without damaging it?
Any help would be great! I don't want to pay $100.00 a fork to let the dealer do it, besides it's more fun to do the work myself.

[xssiveone]

Originally posted by tony7914
Ho what tool do I need to buy to seat the seal without damaging it?

Any round tubular object that will fit over the fork uppers and inside the fork lowers. I used a piece of ABS pipe that I had left over from a plumbing job. Can't remember the size, either 1 1/2" or 2". You don't need anything fancy, just ensure that the seal is driven down evenly.

[TopCatGr58]

Hey Tony,

Here are a few threads regarding Fork Seals:
Fork Seals 1

Fork Seals2

Fork Seals 3

[tony7914]

Thanks for the replies!
I have OEM seals on order and intend to remove the lower tubes to replace the seals. I was thinking of using a big socket to drive the seal into the tube but if there is a softer tool available I would rather go that route.
This bike has turned into a great project for me and I am very happy with it!

I bought the bike a few years back it was in a barn and hadn't been started in 3 or 4 years, the harness was cut up and parts were left off and the tank was dented up.


The picture below is how it looks after I repaired everything.

Since then I have put a double bucket seat on it and a light windshield and some new chrome. soon I'm going to change the cam chain and tensor then rebuild the brake calipers and put in new fork seals. I have this forum and Merriam Cycles to thank for all the information and help when it comes to this bike, you folks are great!

[prometheus578]

I love a good before and after photo spread

One tip not mentioned for fork seals. Before sliding the new seal down the tube to install it, place a lubed piece of plastic, like a piece of ziplock sandwich bag(without the zip, obviously), over the open end of the tube. This prevents the seal lip from getting gouged should the tube end have any scratchies or sharp edges.

[tony7914]

Is it better to install the seal with something inside the lower tube?

Like this.


|_| |_| <- Seal driver or tube of some sort
.. | | <- Upper tube or PVC pipe
._|_|_
|_ _ _| <- Seal
| | | |
| | | | <- Lower tube

And the tool you use to drive the Seal slipped over the tool you have stuck in the lower tube? (sorry for the crappy picture, the dots on the left are nothing.) I planed to remove the lower tube from the bike then drive the seal in with a tube or socket. I wasn't planning on having anything in the middle though.

[prometheus578]

The seal is the last thing I put on, after assembling the whole fork tube. Then you can use a piece of pipe as a "slide hammer" to push the seal down into place.

[Eveready1100]

Hi guys,
I'm having a similar experience as Jamiewalp. My '79 SF started leaking a few months back so I went down to my nearest yamaha dealer (in a major regional QLD town) to order some new seals. After placing my order along with engine/frame numbers and exact model designation and paying (up front) for the replacement seals, approximately 3 weeks laters, I received the call that my special order was at the shop to be picked up. To put it briefly, after a 120 Klm round trip to pick them up, I pulled the front off my bike, dismantled the legs and went to fit the new seals. You guessed it! They were for a Standard. A couple of pointless phone calls to the dealer later, now with my bike unrideable, I resorted to ebay to rescue me from my dramas. Sure enough, within 15 minutes, I had a set on its way from the U.S. They arrived within ten days and as went to put them in, I noticed that they were a lot skinnier than the remains of the old original seals. I was desperate to get my bike on the road again so I milled some nylon down to act as spacers so the seals would seat properly in the leg. Put it all together and went for a run down the road and it was all good.
About 3 weeks later, a familiar oily ring on the fork tubes appeared again and got very much worse quite rapidly. So much so that I've decided to take the fork sliders off my '78E parts bike and fit them to the tubes of my special.
I'll let you know how this thing works out.
I've seen the listing of the part numbers required to restore my special's forks to operational status again, and will be ordering them from Yamaha U.S.A. this week but I just want to get my bike back on the road
Regards
Errol