Prop Shaft Reassembly
MG Midget and Austin-Healey Sprite
by James Reinhard - email@example.com
In his wisdom Donald Healey saw fit to include a closed transmission tunnel in the original Austin-Healey Sprite. This design feature was carried over to the subsequent Spridgets, and contributes to the little car's strength by stiffening its backbone. It's also a good test of backbone for the home mechanic carrying out a universal joint replacement.
Disassembly is straight forward enough: undo the four sets of nuts and bolts holding the prop shaft yoke to the flange on the diff and slide the shaft out past the diff. Mr Haynes in his usual offhand style says "reassembly is simply a reversal of the above process". Mr Haynes lies through his mechanically gifted teeth.
Because the transmission tunnel is fully enclosed, the mechanic cannot simply guide the front of the prop shaft over the gearbox output shaft. Proceed as follows:
1. Remove the steel gear lever turret from earlier cars, or the leather gaiter from later cars.
2. Either roll the carpet forward or cut away some of the excess carpet material to allow a clear view of the rear end of the gearbox extension and splined output shaft.
3. Place a plastic bag over the front end of the prop shaft to protect it from the decades of gunk which will be in the transmission tunnel. If you are a concourse addict, and regularly clean and polish the inside of the tunnel, you can skip this step.
4. Slide the prop shaft into place as best you can, and pull the plastic bag out past the gear lever using Special Tool MGAH-XYZ-037. This tool is made using a piece of stiff wire such as coat hangers are made out of, bent into an L shape. Because Spridgets are British cars, the tool should be 12 inches long, but I believe that a tool of 30 cm long works almost as well.
5. Lie under the back of the car while your Significant Other sits in the driving seat (get used to it) and uses the Special Tool (see above) to encourage proper alignment of the prop shaft front yoke with the gearbox output shaft while you move the prop shaft back and forward as instructed by your SO.
6. Now, finally, reassembly is a reversal etc., etc., etc.
This method works - I know because I have done it twice - but your SO may lose heart if it does not work immediately. SO's do not understand that part of the joy of motor maintenance lies in getting things to work when it appears that they will not! The only alternative to the method described above is to dangle the car perfectly vertically so that the prop shaft can be dangled down the transmission tunnel until it mates up with the gearbox. This alternative method should only be used if you have used it before.
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