Advise on how to re-install my transmission?

[apbos]

Group
My transmission is ready to install on my rebuilt 948. I will have to do this myself, with my motor on a dolly. Initial attempts have not gotten the bolt holes to line up. Difficult to do by yourself. Should I put the motor on it's nose to have gravity work with me while lining it up? Any advise?
Thanks
Paul

 

[Trevor Jessie]

I've not done a 948, but the 1275's seem to slide on with no problem. Did you check for burs on the locating pin/hole.

 

[nomad]

The obvious......clutch centered?????

Kurt.

 

[Guest]

The obvious......clutch centered?????

Kurt.

X2, never really had a problem before. I had one give me some trouble (can't remember which car) and the clutch wasn't lined up perfect. It still went together, just not as easy as it should. Don't force it, something isn't right. There's no reason you shouldn't be able to do it be yourself.

 

[apbos]

I used the centering tool, I will check the postitiion again. I wil check the locating pins again. My dad said to put the transmission is gear so I could line up the splines. I also put some grease in the pilot bushing (may be too much ?). We will try again tonight.
Thanks
Paul

 

[Billm]

If it won't go together the next time try this experiment-
Remove the pressure plate and clutch disk and try to mate them (engine and trans) again. If it goes together then see if the disk will slide onto the trans shaft (without the engine). If the disk DOES slide on the shaft OK then it was a centering problem.
BillM

 

[Bob Claffie]

Most of those clutch disc centering "tools" are next to worthless. Their tolerances and clearances are too great to be any better than a rough guide. The weight of the disc is sufficient to move it off center enough to cause interference. I've often done a better job just eyeballing the components. Whatever you do, DON'T try to draw the engine and transmission together using the mounting bolts. It will slip together with NO force when everything is lined up. Bob

 

[Gerard]

Group
My transmission is ready to install on my rebuilt 948. I will have to do this myself, with my motor on a dolly. Initial attempts have not gotten the bolt holes to line up. Difficult to do by yourself. Should I put the motor on it's nose to have gravity work with me while lining it up? Any advise?
Thanks
Paul

Paul,

Lining up and bringing home any of the A-series gearboxes should be quite easily done single handed. Your mentioning having put grease in the pilot bush makes me suspicious. More than the slightest amount of grease will create a seal with an air pocket behind it that you would not be able to overcome. That's why the technique of removing and old one by filling the bore with grease actually works to drive the pilot bush out. Typically, the pilot bush is oilite, which should be soaked for 24 hours prior to installing. no grease should be necessary.

 

[apbos]

You are all on the correct track. Put a little bit to much grease in the bush and used the incorrect centering tool. I was given both of these when I had the motor at the machine shop. They said they did so little work on A series transmissions and clutches they would not need them anymore. I always "assumed" they were the same. Cleared out the grease and used the "long" centering tool and Bob's your uncle. Thanks for the help guys. I am getting closer!

 

[Gerard]

You are all on the correct track. Put a little bit to much grease in the bush and used the incorrect centering tool. I was given both of these when I had the motor at the machine shop. They said they did so little work on A series transmissions and clutches they would not need them anymore. I always "assumed" they were the same. Cleared out the grease and used the "long" centering tool and Bob's your uncle. Thanks for the help guys. I am getting closer!
View attachment 29199

If you look at my Tech page, you'll see the difference in input shafts between the smoothcase and ribcase.

https://gerardsgarage.com/Garage/Tech/TO_Bearings/tobearings.htm

This is also what you want to use the thicker cast backplate with a ribcase.

 

[apbos]

So I have a set ! Never thought there would be a difference!

 

[nomad]

Most of those clutch disc centering "tools" are next to worthless. Their tolerances and clearances are too great to be any better than a rough guide. The weight of the disc is sufficient to move it off center enough to cause interference. I've often done a better job just eyeballing the components. Whatever you do, DON'T try to draw the engine and transmission together using the mounting bolts. It will slip together with NO force when everything is lined up. Bob

An old trans input shaft works best IMHO. Years ago I picked up a set of line up tools that an E-bay seller had made up for sale. They were cast out of some sort of plastic using molds he had made up from original trans input shafts. They work quite well and the set covers all common British cars. Too bad he didn't keep making them.

Kurt.