FORK SEAL REPLACEMENT

[Kennyg]

While taking my 85 apart for other I thought it a good time to replace the fork seals.Any tips? First attempt at this procedure.Does the anti-dive assembly need to be maintained as part of the system or can it be bypassed or removed? I recall hearing they were not the greatest long term? The forks have to come right off the bike? and what tool removes the adjuster bolts from the top? Thankyou.

[Mark Olson]

Please consult a repair manual before attempting your fork seal replacement.

The anti-dive does not work well and can be removed .

consider getting some later year forks from a 89 fj to 93 and you will be able to have a 17" front wheel and better brakes.

[Kennyg]

Thanks Mark.

[markmartin]

Kennyg,

In the files section  http://www.fjowners.com/index.php?topic=1911.0

The write up includes more than replacing just your fork seals, however it'll give you some better pictures to go along with the directions for changing fork seals in a repair manual, and answer your other questions about tools and removing the forks from the bike. (You won't be cutting your Damper Adjuster Rod or installing cartridge emulators as in the write up)

As recommended to me, it's advisable to change the bushings ( fork tube bushings and fork slider bushings) while you are changing the fork seals.  The bushings are very easy to change. 

[RichBaker]

Please consult a repair manual before attempting your fork seal replacement.

The anti-dive does not work well and can be removed .

consider getting some later year forks from a 89 fj to 93 and you will be able to have a 17" front wheel and better brakes.

Completely removing the anti-dive assemblies requires block-off plates with drilled passages so the forks don't lock up.... IIRC, I have a '90, so don't have direct experience.

[balky1]

Kennyg,

In the files section  http://www.fjowners.com/index.php?topic=1911.0

The write up includes more than replacing just your fork seals, however it'll give you some better pictures to go along with the directions for changing fork seals in a repair manual, and answer your other questions about tools and removing the forks from the bike. (You won't be cutting your Damper Adjuster Rod or installing cartridge emulators as in the write up)

As recommended to me, it's advisable to change the bushings ( fork tube bushings and fork slider bushings) while you are changing the fork seals.  The bushings are very easy to change. 

Eeeeehmmmm, resurrecting an ages old post, but why to create new one, I think this one will do just fine. 
After having a clunk sound when going over bumps for some time now and I wasn't able to find the source, I guess the fork bushings finally worn out enough so that I can detect the free play. And yes, I checked the steering stem, wheel bearings, etc. and I'm positive the fork bushings need replacing. Strange enough, the forks don't leak yet. Maybe I've noticed it just in time before the seals got damaged (yes, there is oil inside).
To cut the story short, I've read the instructions provided in the qouted post and Clymer and I have a couple of questions:

• Is it possible to unscrew the damper rod (the bottom screw that holds the legs together) without the special long hand-made tool, i.e. without holding the damper rod from inside? For example by leaving the spring inside to create pressure or by not removing the damper rod locating screw prior to unscrewing the bottom screw? Would that damage the locating screw?
• When assembling, again, is the locating screw strong enough to hold the damper rod while torquing the bottom screw?
• Is it possible to remove just the bottom part, without removing the stanchions? I guess it would be hard/impossible to install the seals?
• Will the front end be high enough for this job when on the center stand, tilted backwards?

I think this covers it for now. 

[balky1]

I've read the manual again and interestingly it doesn't say you are supposed to unscrew damper rod locating screw prior to unscrewing the bottom allen bolt. But then on assembly part, the screw is out.
Help! 

[Sparky84]

My workshop manual says take out damper rod stopper (locating) screw just prior to unscrewing the bottom Allen bolt

[balky1]

Thanks!
There have been posts about Clymer being somewhat inaccurate when it comes to fork disassembly (and lacks some things obviously). You have just confirmed it to me.

[FJ1100mjk]

A. When assembling, again, is the locating screw strong enough to hold the damper rod while torquing the bottom screw?

B. Is it possible to remove just the bottom part, without removing the stanchions?

A. Possibly, but not advisable. Better to fashion a tool to hold the damper rod from turning, so that its screw can be loosened or torqued properly. If the locating screw is bent, you won't be able to remove it again.

B. Yes, once the damper rod screw is out, the lowers/sliders pop apart from them. But why bother? Your 98% of the way completed with the disassembly at this point anyways.

[racerrad8]

Balky,

Sorry I missed this yesterday.

1) You can remove the allen screw from the bottom without the tool... sometimes. Other times it just spins round & round.

There have been plenty of photos of tools made using a bolt driven into a socket to hold the damper rod posted on the forum over the years. There has been stories told of using the end of a broom handle to wedge again the damper rod.
Or you can buy the correct tool for the job: 27mm Fork Tool

2) Remove the damper rod indexing screw. It is not there for disassembly or assembly purposes. The screw can get bent or crushed during that process. I use a punch that fits the threads snugly, as well as the damper rod tool to index the damper rod during installation. The punch is there just to index, the tool is what I use to hold the damper rod.

3) Yes, you can remove the lower slider without removing the fork. But, you will not be able to replace the fork seals.

4) Yes, you can push the back of the back down on the center stand to remove the wheel, then you have plenty of room to remove the forks.

Your source of the clunk one thing other than fork bushings. I have seen the damper rod installed onto the location screw which caused the damper rod to be off center and come loose.

I have attached a couple of photos of a damper rad that was tightened, and came loose on top of the locating screw.

All of your fork rebuilding parts are in stock and ready to ship once you get them torn down.

On more thing, don't forget about the fork seal driver 41mm Fork Seal Driver. Not only does it allow you to install the seals and wipers in seconds, it will easily install the new upper bushing into the top of the forks too.

Randy - RPM

[balky1]

Thank you all for the advice. Very helpful and all my doubts and questions are now answered. 
Randy, I'm pretty sure the bushings are culprits. I put the bike on center stand and lifted the front wheel. Stood in front of the bike and grabbed the forks at the level of anti-dives. Pulled and pushed and there was a sound and feeling of free play. Then I grabbed on the stanchions and did the same to rule out steering bearings and no free play observed.

[racerrad8]

When you take them apart, look at the bottom of the damper rod and see if there is damage like in the photos.

Also, if the screws do not come out easily, they are probably pinched in there. At that point loosen the damper rod and then they will unscrew.

Randy - RPM

[simi_ed]

I'd bet the bushings are indeed worn out. As a rule I never will replace fork seals without doing bushings also. It's just too much of a PITA to do seals and not bushings at the same time.

My 2¢

[balky1]

I'd bet the bushings are indeed worn out. As a rule I never will replace fork seals without doing bushings also. It's just too much of a PITA to do seals and not bushings at the same time.

My 2¢

I know the feeling when you just assembled something and a week later you see you have to disassemble it again because of some other thing. I took the rear wheel down at least four times in the last 2-3 months.