Bridgestone Motorcycle Parts Discussion Board

Bridgestone Tech Talk => 350 Talk => Topic started by: mrjones on September 13, 2021, 04:51:57 PM

Title: clutch pushrod seal
Post by: mrjones on September 13, 2021, 04:51:57 PM
hello everyone from a uk member! my clutch pushrod oil seal is leaking and i need to change it, can i do this without stripping the engine down? and what is the correct size? as im sure one from another bike would fit, thanks Marcus
Title: Re: clutch pushrod seal
Post by: mrjones on September 13, 2021, 04:56:00 PM
ha ha! i forgot to say the bike is a 350 gtr !
Title: Re: clutch pushrod seal
Post by: BRT-GTR on September 14, 2021, 09:33:38 AM
    Hi Marcus,
         I assume you mean the seal on left side of engine where push rod enters the clutch shaft. This is a 17x28x7 seal, available from any good bearing/seal supplier.
    I use 'Simply Bearings' here in the UK, here's a link to the seal  https://simplybearings.co.uk/shop/p70270/17x28x7mm-TC-/-R23-Double-Lip-Viton-Rubber-Metric-Rotary-Shaft-Oil-Seal-with-Garter-Spring/product_info.html (https://simplybearings.co.uk/shop/p70270/17x28x7mm-TC-/-R23-Double-Lip-Viton-Rubber-Metric-Rotary-Shaft-Oil-Seal-with-Garter-Spring/product_info.html)

    This seal has a second rubber lip on the outside to exclude dirt and grit which is a good thing near the chain sprocket.
    I don't know if seal can be installed from the outside, they're usually clamped between the cases when rebuilding an engine.  But, you have nothing to lose by giving it a shot.
       Brian.
Title: Re: clutch pushrod seal
Post by: mrjones on September 14, 2021, 12:10:02 PM
 thanks for that Brian ive ordered one! my pushrod is 6mm diameter but fits in an 8mm gap (the worm drive is 6mm though) is this right?
Title: Re: clutch pushrod seal
Post by: Steve Swan on September 14, 2021, 02:15:35 PM
hello everyone from a uk member! my clutch pushrod oil seal is leaking and i need to change it, can i do this without stripping the engine down? and what is the correct size? as im sure one from another bike would fit, thanks Marcus

Hi Mr. Jones,

One of the last shops i worked at primarily serviced bike out of the 60's through the 80's.  It was common practice to replace leaking seals without dismantling anymore than was necessary to remove the seal.  There are a number of approaches to remove a seal, the most common is to screw in a self-tapping screw through the metal housing of the seal and then get on the screw head with a pair of pliers and pull the seal out.  The best way to put a hole in the seal's metal housing is source a metal or drywall screw, use an electric drill to drill a tiny hole in the metal housing and then thread the screw into the housing or use a hammer and tap the screw in enough to make a hole in the housing, then thread the screw in.  Whichever approach you decide depends on where the seal is, how easy it is to get to and how big the seal is.  It's very helpful to only make a tiny hole so you can start the screw and so the screw has as much "purchase" as possible.  The other approach is to use a small punch or small sharp chisel, make a hold in the housing so that you can use a screwdrive to prise out the seal.  Like any process, depending on what tool selection you have at your disposal, give thought to what tools will work best for you to do the job and how you will carry out the procedure.  I've replaced many seals this way.  My friend who is doing the work on my GTR, his is the last shop i worked at as a mechanic, he has replaced all the seals external to the eye on my GTR using the very same methods i am describing to you.  Give your project some forethought, take you time and you'll do fine.  The other consideration, have the area entirely clean before you begin to remove the seal.  Then grease the seal, wrap a single sheet of saran wrap around the shaft, smear some grease on the saran wrap and slide your seal on.  Prior to being at this point installing the seal, find the appropriate sized drift that you can use to push by hand or using a small hammer to tap the seal home.  in your case, there's not much of the shaft protruding, so give the seal and the shaft a film of grease, then install your seal.