Replaced fork seals, leaking at air valve?

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JustinM

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So I replaced my fork seals (93) according to my Haynes manual, and it seems they dont want to hold air pressure now. I removed my dust caps and a bit of fluid was on top of the fork. It could be the upper o-ring also, but is it a common problem to have the air valves leak? Also is there a way to double check fluid level after the forks are installed? Thanks, Justin
 
So I replaced my fork seals (93) according to my Haynes manual, and it seems they dont want to hold air pressure now. I removed my dust caps and a bit of fluid was on top of the fork. It could be the upper o-ring also, but is it a common problem to have the air valves leak? Also is there a way to double check fluid level after the forks are installed? Thanks, Justin

See the attached schematic.

Parts numbered 3 and 7 are the o-ring air (and oil) seals for the air suspension system and 5 is the air valve.

If the o-rings are old and flattened they will probably not re-seat properly and subsequently leak.

Use new ones.

See the two red arrows in the schematic?

Those nuts clamp the air-pressure balance pipe between the forks. They achieve their seal with nylon washers and can also leak if incorrectly seated or tensioned.

To test all these connections for leaks prepare a bit of detergent and water in a spray bottle, pump about 14 psi into the forks and spray the mix on these points.

Spray around the new fork and dust seals as well.

If it bubbles, you've found your leak.
 

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You did put the seals in the right way right? Not upside down?:confused2:

As for air... You are better off spending a little dosh on a real set of springs and using NO air.:thumbs up:
 
You did put the seals in the right way right? Not upside down?:confused2:

As for air... You are better off spending a little dosh on a real set of springs and using NO air.:thumbs up:

I'll vouch for that. Mine rides a millions times better with the racetech springs with no more worries of air. The local shop charged me $76 dollars to change the springs and seals and change the oil to 15 wt.
 
Even stock springs with thicker oil and no air works quite well.

Sean
 
Well no oil leaks anymore, must have been just residual. The front just feels spongy, perhaps because its all stock. Can you fill me in on changing to thicker oil? Budget won't allow for new springs at the moment, would 15 or 20wt be better with no air? My main issue is nosedive under braking. Thanks, Justin
 
Well no oil leaks anymore, must have been just residual. The front just feels spongy, perhaps because its all stock. Can you fill me in on changing to thicker oil? Budget won't allow for new springs at the moment, would 15 or 20wt be better with no air? My main issue is nosedive under braking. Thanks, Justin

most are running 10-15wt with aftermarket springs, with stock springs I don't know but proabaly 15 wt or even thicker .....



Rusty
 
I'm running 20w with stock springs & leak-proof seals & I don't have an issue with diving. I know the leak-proofs will start leaking in about a year, but I was in a hurry & leak-proofs were available. Will probably upgrade springs someday, but now I'm saving for a new clutch.
 
20w works well. If it ends up being too stiff you can back out to 15w.
 

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