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Old 03-15-2009, 06:19 PM   #14
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Re: 94 Metro 5 Speed Manual Transmission Rebuild - PART 2 - Assembly

The Gear Shift and Selector Shaft Assembly (which I never disassembled) was returned into the case.

Some Motor Oil was dripped on the Shaft before it was pushed in.

Make sure all the Shift Forks inside the case are lined up.

You have to hold the Gear Shift Interlock Plate horizontal as you insert the Rod as it must pass thru
those "Shift Forks" that shift the Gears.

Here is a close up of those "forks" and the Interlock Plate.

The Interlock Plate restricts the Shift Forks such that only one at a time can be moved.

This keeps the transmission from going into two or more gears at the same time.

The Mechanical Engineers who designed this stuff get all my admiration!
This transmission is a mechanical wonder to me - I cannot fathom an automatic transmission!

The Shift Yoke was installed by lowering it into the Case on a hooked piece of Solder Wire (easily bent).

The Yoke has a tilted top which needs to be tilted to the left side when looking at the case as in the photo.

You have to pull the Gear Shift and Selector Shaft Assembly out a few inches so that the Yoke can
pass by it into the case and be set onto the Shift Lever.

For God's sake, don't drop it into the case - you may have a Hell of a time getting it back !

Once you have the Shaft thru the Yoke, you must push the Gear Shift FORK on the outside bottom of the Case
in so that the hole in the Yoke lines up with the threaded hole in the Shaft - otherwise the bolt will not thread into the Shaft threads...

The Bolt with Blue Threadlock was threaded into the Yoke thru the Shaft and was tightened to 20 ft lbs.

Notice that there is a round "Plug" next to the Shift Shaft and Yoke with a Magnet in it. Why ? idea.

The Gear Shift Interlock Bolt was put in with Blue Threadlock and hand tightened - see the third photo above.

This Bolt keeps the Selector Shaft from going just any old place by riding inside a machined slot
on the Selector Shaft - see first photo above - inside that "Rotating Cage" is a pattern cut into the metal.
Looks like three circles side by side.

The the Bolt rides inside of that slot and the Shift Rod is restricted to that motion only - by the Bolt.

Now......I tried to move the Gear Shift Mechanism by trying to move the Shift Fork at the bottom outside of the case - Ha !

The Gear Shifter inside the vehicle has about a 5 to 1 mechanical advantage when one shifts.
Push the Stick 5 lbs and the Shift Fork gets pushed with 25 lbs...!

I cannot apply enough force by hand to get the gears to shift !

Neutral appears to be the position the Selector is in normally - all forks are lined up.

I turned the Input Shaft (IS) and everything turns - however, if I hold the Countershaft still, the IS still turns,
so the turning is just a form of drag.
i.e. the Transmission is in neutral.

The gear shift pattern will be a mirror image of the shifting pattern one uses inside the vehicle.

Have to figure something out to test what I have rebuilt (a Frankenstein?)

Maybe I will remove the Bolt from the Yoke, take out the Yoke and put a rod (Phillips Head screwdriver)
in the end of the Selector Shaft threaded hole to rotate it into the gears....


Last edited by DOCTORBILL; 03-16-2009 at 11:12 AM.
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