Success report: changed fork seals without separating fork tubes

[t3rmin]

http://img218.imageshack.us/img218/7286/seal3sm5.jpg Just make sure your fork is fully extended, drywall screw, pull old seal out. No pressurized oil vapor blowing around and no mess either.

Hey that's a good idea too. Maybe one on each side and you can work it out evenly?

[t3rmin]

ok, I tried this the other night... Of course I tried the one that WASNT leaking first. I got the dust cap off and noticed it was all rusty underneath. no problem I thought, all the more reason to change it... took the spring out, hooked up my air, and put a little in... the forks extended, but that was it... little more air, nothing... I checked the pressure, and had 89PSI in there... and it wasnt budging.... I didnt think of using a manual pump though...

the other seal should come out fairly easy, though...

I just kept the air chuck on there and air flowing 'till the seal popped. Dunno how much pressure it took, but it very well might have been more than 89psi. Any reason you didn't just let loose with it? I doubt your average consumer-class compressor has enough power to damage it or be terribly unsafe, even if you tried.

[salty_monk]

Well thanks for the tip, I used this method on mine this evening & it worked great.

I used a bicycle "track" pump (stirrup type) rated to 160 PSI.

For info the better sealed fork leg showed around 170 PSI (right off the gauge) before it went & the bigger leaker went at around 155PSI. Nate you need to keep filling!!

Progressive fork spring fitted with 40mm spacers & 15wt oil. Just need a couple of new nuts & bolts for the top clamps on the forks & I'll be test riding.

Interesting that when I got it off I realised that the old forks with no air (always struggled to get the right amount of air in there) were about halfway through their travel with me on board. Now it's around an inch.

To fit the new seal I used a 2' length of 1-1/2" waste pipe from Home Depot. About $1.50..... Slid over the top & tap in to place.

Thanks once again for the tip.

Dan

[Billy Ricks]

I took mine totally apart. New fork seals and steering stem bearings. Now Im wondering about the reassembly. what gets tightened first ? Steering nut, upper & lwr fork tree, front wheel axle ? Whats the proceedure to get everything aligned back up ?

This answer is a little late, but for future reference you start at the axle and work your way up.

[mortation]

OK Now this I am gonna try. Exactly the half baked way to do things I wish the picture would load on the original link though. I like pictures

[SabreJim]

I have always poked a small screw driver into the body of the seal (since its trash anyways) and popped it out without any problems.... seems to me the air thing is just another method. End justifies the means as long as no dammage is done 8-[.

[bonanzadave]

This answer is a little late, but for future reference you start at the axle and work your way up.

Thanks Billy,
Thats what I did. Since then I had one of the seals from Bikebandit leak. I got another one from Z1. Much better seal. There was no way I was gonna disassemble the whole thing again so I jacked the bike up in the air and got the fork tube slid down out of the top and bottom trees. I didnt use the air method I just pryed the old seal out. Slipped fit the new seal for the old and in less than an hour Im back on the road. \\/

[mortation]

OK I made the link into a PDF document with the images. If anyone wants it PM me.

[longgreensilverado]

ok i'm going to stir up the pot: I'm not a fan of this method for a few reasons. First, when you drain the oil out of the top cap or drain screw at the bottom there is still quite a bit of residual oil in there which could effect your oil level and thus blow out the new seal. Second, you risk ruining the fork leg by using foreign tools that can scratch and mar the surface that the seal rides against. on my 1980 gs850g i remove the forks, wipe them down of all dust and gunk. remove the top cap and spring. then you will need an 8mm allen wrench for the bottom and a 19mm bolt with nuts on it. this 2.00 handy tool will go into a 19mm socket where the end of the bolt sticks out enough to fit into the fork leg (you will need a long extension 1/2" drive is best for rigidity inside the tube) this way you can seperate the fork halves and be able to clean out the old oil which turns to gunk and can cause other issues.
when reassembling put the seal in and then slide the fork leg back together and tighten up. this way the seal is not "poked at" .

[t3rmin]

ok i'm going to stir up the pot: I'm not a fan of this method for a few reasons. First, when you drain the oil out of the top cap or drain screw at the bottom there is still quite a bit of residual oil in there which could effect your oil level and thus blow out the new seal. Second, you risk ruining the fork leg by using foreign tools that can scratch and mar the surface that the seal rides against. on my 1980 gs850g i remove the forks, wipe them down of all dust and gunk. remove the top cap and spring. then you will need an 8mm allen wrench for the bottom and a 19mm bolt with nuts on it. this 2.00 handy tool will go into a 19mm socket where the end of the bolt sticks out enough to fit into the fork leg (you will need a long extension 1/2" drive is best for rigidity inside the tube) this way you can seperate the fork halves and be able to clean out the old oil which turns to gunk and can cause other issues.
when reassembling put the seal in and then slide the fork leg back together and tighten up. this way the seal is not "poked at" .

Draining out of the top cap with the fork upside-down while pumping it is very thorough. At this point you could also use something to flush out any old oil/grime residue. And nothing is stopping you from using some kind of "dip stick" measuring method after re-filling to insure proper levels.

In no way does this method risk marring the tubes -- it's less involved than complete disassembly and I daresay *less* risky in that respect. I did mine without ever touching the tubes with a tool ("foreign" or otherwise).

The new seal is never "poked at" or otherwise molested. Driving it home with PVC pipe or the old seal is perfectly safe.

Done properly, this method is safe and easy. If you want to do it the hard way, you have my blessing, but don't unduly discourage others.

[salty_monk]

It worked fine for me. I used ATF (cause it's cheap) to flush out the tubes & get rid of old oil then flushed with fork oil before filling.

To get a level I took the top off a spray bottle, cut the small tube to the right length then put it on the top of the fork (cap rests on the top, tube in the oil) then pull the trigger & spray excess into a cloth. I checked with a depth gauge & it was spot on.

There is no risk to the fork legs. I used plastic pipe like a slide hammer to insert the new seal.

Dan