RestoCycle How-To: Replace an engine oil seal
Posted: Tue Apr 01, 2025 10:19 pm
Moving over some content I created on Facebook for safer keeping here. This one may seem elementary to many of you.
A mini-tutorial on how to install a shifter shaft seal into a Honda CBX - but the techniques will work for most any old motorcycle.
OK, here's our patient, a 42 year-old shifter shaft seal from our 1980 Honda CBX project. It's not leaking, but quite a lot of the rubber parts on this bike were hard and punky, and it's just a good idea to replace this while the engine is empty of oil and easy to access.
This is everything we may need, plus a few drops of clean motor oil.
This is how we'll extract this seal, with this wimpy-looking pick. This particular seal is not metal-reinforced, and that makes removal and installation easy. Once in a while, a stubborn seal will require more drastic measures to get a grip on it to remove, including driving a wood screw into it, and then yanking it out by the screw with pliers. You have to be very careful not to damage the seal pocket, whatever method you use. This is pretty safe, but even so, we're going to take care not to scratch the aluminum seal pocket with the steel pick.
Stab it dead center of the rubber part, being mindful of where the tip of the pick will end up. What you do NOT want to do is gouge the soft aluminum of the seal pocket with your sharp pointy steel tool.
A mini-tutorial on how to install a shifter shaft seal into a Honda CBX - but the techniques will work for most any old motorcycle.
OK, here's our patient, a 42 year-old shifter shaft seal from our 1980 Honda CBX project. It's not leaking, but quite a lot of the rubber parts on this bike were hard and punky, and it's just a good idea to replace this while the engine is empty of oil and easy to access.
This is everything we may need, plus a few drops of clean motor oil.
This is how we'll extract this seal, with this wimpy-looking pick. This particular seal is not metal-reinforced, and that makes removal and installation easy. Once in a while, a stubborn seal will require more drastic measures to get a grip on it to remove, including driving a wood screw into it, and then yanking it out by the screw with pliers. You have to be very careful not to damage the seal pocket, whatever method you use. This is pretty safe, but even so, we're going to take care not to scratch the aluminum seal pocket with the steel pick.
Stab it dead center of the rubber part, being mindful of where the tip of the pick will end up. What you do NOT want to do is gouge the soft aluminum of the seal pocket with your sharp pointy steel tool.