If your trans has the small, bullet type housing, they can be a little loose...not really much to hold them tight. There are two seals...an o-ring around the outside of the bullet, and the seal that seals the gear itself. You can loosen the 7/16" bolt that holds the small tab/bracket on, and let it flop down. Then, the bullet will pull right out. You might loose a couple of drops of fluid... not much, but have a drain pan, or something to catch what does drip out.
The o-ring fits around the outside of the bullet, and changing it is just remove/replace.
The inner seal, depending on what type is has, will be a little more challenging. There are a couple of different style of seals for that. Originally, is should have a metal clad seal. Changing it requires prying it out with a small screwdriver. Replacing the metal clad seal requires a small socket, that will just fit down inside the hosing, where the seal fit. Place the seal in the housing, and use the socket, and small hammer to tap the seal down until it stops. That's it.
Most replacement seals, and later model original seals are just rubber....no steel. They are held into the housing with a small, round, metal clip. A small screwdriver will pop it right out, and the seal after that. Installation is just the reverse...seal, then clip. On the rubber seals, you have to be careful to not push it down in the housing too far, as it will distort, and not seal well.
In the last pic I posted above, you can see the inside seal. This is the seal that the speedo gear ride in. You must check the end of the plastic gear, where it rides ont he seal, because the seal, regardless of the type of seal it is, can wear the gear down,a nd put a groove in it. If the gear has a groove, the seal will not seal, and it will leak....the gear will need to be replaced.
Also, if your speedo bullet is aluminuminum, you'll need to remove the gear, and look down into the hole, where the gear runs. If the bore is egg-shaped, the bullet will need to be replaced.
It's not really hard to fix the leak...just a couple of seals, and maybe 30 minutes of time.
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Joel Adams
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