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Hijacker »
https://forums.nicoclub.com/hijacker-u9394.html
Mon Sep 10, 2007 12:16 pm
This tutorial is to help those who have had their SR transmissions go bad on them. KA 5 speeds are a bit more abundant, and aside from a slight change in 5th gear, are identical to the SR trans. The only major obstacle to overcome is that the bell housings bolt to their respective blocks differently.
This tutorial will help you tear the trans down all the way so you can inspect the gears, but I will not supply information on rebuilding the gear sets if yours is having problems.
WARNING! There will be lots of stinky, nasty, and all around obnoxious gear oil. Plan on making a mess.
I did this swap using an S14 manual trans we had. Some of the pictures will differ slightly, but the procedure between an S13 and an S14 transmission should be the same.
You can see the obvious differences in the bolt pattern.
The backsides are identical though.After you have your transmissions disconnected and sitting free, you can start the transplant. This tutorial will cover mating a KA tail shaft housing and gearbox to an SR bell housing.
Remove the gearbox breather tube, throw out bearing, and clutch fork as well as the rubber clutch fork boot. This will give you access to the front cover inside the bell housing. Remove its bolts and pull it off. If it’s giving you trouble, you can work a pry bar in through the clutch fork hole and place it on the clutch fork pivot. A few taps should knock it loose. There’s a shim that is placed on the countershaft bearing. You will need to save that. There is also a big retainer clip around the input shaft bearing. Get a ring spreader and pull it off. A pick can help a ton here too.
There's the nasty nasty ring.
Now get a couple small pieces of 2x4s and set the trans up on them with the bell housing facing down.
Next is to get the tail shaft housing ready to come off. There is a small plate held on by 2 10mm bolts. It prevents you from going into reverse while moving. Note its orientation and pull it off. Next pull the two spring retaining bolts from the shifter housing. Both have springs beneath them, so be careful. You should be able to pull one half of the plunger out. The plunger is in two halves and keeps the gear selector from rotating.
The two parts that need to come off.
Now pull the bolts holding the two halves of the trans together. Take a mallet and knock the housing loose. The ears for the trans mount bracket work well for a spot to hit. Rotate the gear selector as far to the left as possible (towards the driver side). It should pull up easily. If it has resistance, it hasn’t cleared the shift forks and is still hung up on them. I suggest getting a feel for how the forks maneuver around the shifter linkage. I would pull the tail shaft housing off and put it back on so you know how everything should be oriented.
Now you can remove the bell housing from the gears. Lay the unit back on its side with a block of wood propping it. Take your mallet and hit the input shaft to start separating the sandwich plate from the bell housing. It will come with enough persuasion. Just don’t get too mallet happy and accidentally knock the bearings out of the sandwich plate. You could also use a screwdriver or a pry bar as a wedge and separate the sandwich from the bell housing as well. Just be careful not to tear up any of the mating surfaces.
You should be left with this.
Take the time to inspect your gears for unusual wear, wobbly countershafts, or anything else that may stick out to you.
Repeat all of that for your other transmission.
Reassembly is pretty much the reverse of the teardown, just be careful when you’re reattaching the tail shaft housing. It takes some practice to learn how to maneuver the housing on without getting hung up on the shifter forks. You will know if you do get ‘em hung up. They usually knock a fork forward, which you can see from inside the bell housing. Just get a feel for how you took it off.
Make sure to reapply gasket maker to both sides of the sandwich plate, and sometimes a thin layer on the plate inside the bell housing helps too in case your gasket in there got a tear in it.
Now you can drop this trans back into your car!
It is possible to change just the bell housings and leave the tail shaft housings on. Remove the plate and snap ring inside the bell housing and then pull the bolts and knock the bell housing off. Use the input shaft and you should be able to keep from breaking the gasket seal for the tailshaft housing. Reapply gasket maker and put the new bell housing on. Quicker, easier, but you won't know what shape your gearbox is in.
I will try to clarify this and update it so it's more legible as I get more feedback. Please PLEASE don't bug me on AIM about this procedure.