Topic: Cb750a 78 left case removal

[Remcod]

Hi,
I’m trying to remove the left case with the shift mechanism to change the gasket because of an oil leak.

Now the shop manual says remove 3 screws and then the case, apparently with no need to remove anything else.

I removed the 3 screws but it will not release, can anybody confirm that you only need to remove these?

Thanks,
Remco

[sammon287]

  I just did it a couple days ago on my '76. Once you remove the three screws, the left case comes off with the shift mechanism intact. Mine took a lot of force to break the hold of the gasket. I had a piece of 2x4 near the counter-shaft and pried against the back side of the left case with a big pry bar trying to stay near some reinforcement webbing. Be careful about applying lots of force to any of the cast aluminum. Spread the load out. The left case cover was similarly hard to break loose.

[Remcod]

Ok thanks, I give it a try

Any chance that the shaft seal can be replaced without splitting the case?

[Medyo Bastos]

I don’t remember them being that tough. Tap around the edges of the cover with a rubber mallet to be sure everything has seated.

Are you talking side cover seals? Ive taken those out with drywall screws before.

Sent from my iPhone using Tapatalk

[sammon287]

Ok thanks, I give it a try

Any chance that the shaft seal can be replaced without splitting the case?

If you are only trying to replace the shaft seal, that's on the case cover which has more than three screws, just to be clear. I think it would be possible with the drywall screw technique mentioned above. The shifter and neutral safety shafts appear to use the same seal size, but the kickstart seal is different. Where did you get your seals and gaskets? I had no responses to posts and PMs on that topic.

[Remcod]

Managed to get the case of, required indeed force, same for the oil pump.

Glad too because a piece of the neutral stopper shaft was broken off ages ago and resting in the case. Let’s see if I can find one, probably eBay with high shipping unfortunately, problem of owning an automatic in Europe

The side cover seals I will get of no problem, I was referring to the countershaft that I suspect to be the culprit, so I was wondering if anyone removed and replaced it without splitting the cases. I noticed it’s 2 pieces, perhaps removing the outer one would do the trick, but I’m not looking forward splitting the cases, usually one thing suddenly becomes many things.

I sourced the seals and gasket from cms

[sammon287]

That site is helpful (cmsnl.com) and I see those seals are available.

[Remcod]

Just went for a test drive, unfortunately still leaking, but for sure it’s the countershaft seal. Anybody having experience pulling it without splitting the cases? It’s a 2 piece seal so I’m very curious. Otherwise my next winter project just volunteered.

Also interestingly the shift light went from neutral to 1 and to neutral instead of 2. It didn’t do that before I took it apart, something to look into also.

Feel free to share your thoughts

Thanks,
Remco

[sammon287]

  It is not possible to change both seals without splitting the cases. I actually removed them yesterday with my cases split. The inner seal has a metal outer circumference that fits in a groove in both case halves. The outer seal was so firmly stuck to the upper case, it took all my strength to pull it out (up) from the case using a rag looped through it as a handle. The outer seal is not in a groove, so it could be possible, but I think it would be exceedingly difficult.
  Having recently removed the left case, I would guess you crossed the wire connections for the gear indicator on reassembly. 

[Remcod]

Ok thanks, a winter project it is.

[jonnycakes]

I've replaced the outer counter shaft seal with out splitting........easy

[sammon287]

I've replaced the outer counter shaft seal with out splitting........easy

How did you do it? Screws and slide-hammer? I could barely budge it with it only stuck to one case half. Was yours ever removed before? Mine was likely the original from 76.

[jonnycakes]

got a shirt wrapped around the countershaft, ruined the outer seal............big screw and pried it out and drove in a new one