FS4W71A Transmission Assembly Photos (Jan 1971 240z)

[240260280z]

I just refreshed a transmission and took pics as I disassembled and reassembled.

There aren't many pics on the net so this will hopefully help others.

Parts: 3 Gaskets, 2 front bearing shims, 1 front bearing clip, 18 M8 X 1.25mm bolts, drain/fill plugs, speedo gear w locking clip and bolt. Not included: throwout bearing, throwout collar, fork, spring clips, slave cylinder (will be added to post later)

Rear most housing with the famous "monkey motion" assembly.

Inside the rear housing. You can see the striker rod that is driven by the money parts. It was bent and slightly deformed in this old transmission making removal of the rod and the rear part of the housing difficult. Some filing helped sort it out.

End of transmission where the drive shaft connects. The rear seal is removed.

Hole where speedo gear connects. It was difficult to remove the gear. I had to spin it with a pipe wrench. The speedo is sealed with an O-ring and a simple clip holds it in place.

Here is the speedo gear. The area above the o-ring corrodes overtime and causes it's resistance to removal. When reassembling I used lots of antiseize above the o-ring and lithium grease below it.

Front face of the middle housing

Inside the middle housing. Not much exciting except for the drain and filler plugs

Front bell housing

Another shot of bell housing. It is easy to see the tube where the throwout bearing and collar slide up and down. I had to use a scotchbrite pad to clean it up as it was corroded. Before installation I will use a high temperature urea based grease for these parts. You can also see the pivot for the clutch fork (removable) and the hole where the fork is connected.

I chased all holes and bolts when dissembled and used lots of anti-seize when reassembling.

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Back side of front bell housing. Front seal is removed

New rear seal ready for installation. This is a black-dragon beck/arnley part that is smaller in thickness than the original Nissan part.

Guts

More Guts

Where the striker rod connects to push/pull the rods/forks. Top is 1&2 gear, Middle is 3&4 gear, bottom is reverse with a protective button and spring to prevent accidental shifts into reverse. This protective mechanism was seized on this transmission and had to be disassembled and filed as well as a spring shortened to work again. The spring that was shortened is inside that point metal part of the housing attached to the end of the reverse rod. It has a ball bearing mechanism similar to those in the shift rods.

Front bearings. Big main drive bearing on top and smaller countershaft on bottom

More gears. The bolts in the main plate/adapter hold small ball bearings and springs. These hold the shifting rods in place. You can see a groove in the lower shift rod (reverse) where the ball bearing engages. This occurs when the rod is pushed forward (since the stick shift is a lever, pulling the stick back into reverse actually pushes the rod forward.

More details

Even more. Note the brass syncros. GL5 gear oil likes to eat these so always use GL-4 in your transmission and GL-5 in the differential.

Reverse Gear

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Shot of striker rod (lurking in the dark like a moray eel) and the shifter rod ends where it engages. Note that the reverse rod is forward and engaged. When reassembling, all shifter rods should be in neutral.

Rear housing in place. I reused the paper gaskets. I just scrapped off the "gunks and chunks" with fingernail and wiped with alcohol. I used Pematex Aviation Gasket Maker (applied to both metal surfaces and both sides of the gasket).

Middle housing being positioned.

Front view of middle housing in place. I used lithium grease on shifter rods and gears to help but it is not really needed.

The reverse assembly protection mechanism. The unit was seized. There was no corrosion and no significant signs of wear however I could not shift into reverse. To correct the problem I has to file the plunger/shaft part on each side of the "mushroom" end and I also had to cut two coils from the small thin spring. You can see the groove in the plunger/shaft part where the ball bearing seats.

Front main bearing. The circular clip is installed that holds it in place.

Two bearing shims. The new front seal is in place.

Countershaft bearing shim in place. I used lithium grease to hold it in place. The main drive bearing shim gets installed in the front bell housing just on top of the seal.

Speedo gear in place. I used antiseize above the o-ring to keep water out and make next-time removal easier.

Front bell housing bolted in place. Same routine for the associated gasket on the other side.

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Closed up and ready for installation. A coat of silver paint and it will look mighty purdy.

Note the disassembled motor parts and the differential ready to go.

[240260280z]

Edited July 8, 2011 by Blue

[Arne]

Great pictures! BT,DT.

[bpilati]

Good job, Blue. Thanks.

[steve91tt]

This is outstanding. I have read and followed your writeups for many other tasks in the past. Your pictures always make things easy. I'll be rebuilding my early 4 speed soon. This will be a great resource. Thanks!

[chaztg]

excellent pics...the Haynes manual people should look u up! When can we see the 2000 Roadster 5-speed conversion into an early Z? Just a bell housing swap, or does the mainshaft also have to be changed?

[240260280z]

Edited July 29, 2011 by Blue

[240260280z]