004 Rebuild

[Bill K.]

Ready to rebuild 412 manual transmission.

Spare tranny from '74 coupe clean and ready for overhaul.


Known parts:
1. Replace oil seal for adjusting ring (final drive seal, 113301189F), qty 2
2. Replace bearing cover seal (main input shaft seal CR-6620)
3. Reuse or replace nosecone bushings/seals (001301200/ 001301227)
4. Replace ground strap (251971237)
5. Reuse oil seal for bearing cover
6. Clean, seal, and reuse gaskets
7. Differential bearing, qty 2 113517185C

Modified parts (click link to go to post):
1. Replace/reuse countershaft with 18mm chromoly shaft for use with Torlon bushings
2. Upgrade countershaft needle bearings to Torlon
3. Replace oil ring for mainshaft carrier / side adjusters

Unknown parts/mods:
* Replace pinion bearings, qty 2 - need to pull bearings for exact number
* 4th gear main shaft needle bearing - Ray p/n?
* Shim spider gears - Ray?
* Replace or shim tube spacer between stub axles -- Ray?
* Shim synchro rings - Ray?
* Other???

Updated:
* 2/27 for revised parts, links within topic
* 3/1 for reuse of good countershaft if using Torlon bushings, add diff bearing p/n, clarify pinion bearings have unique p/n

[raygreenwood]

First OFF: DO NOT at any time until we get there..remove a single part from the differential end. Since certain tools donot exist for this transmission....certain relationships must be measured as we take them off....and that comes last.


Ok....some things to know. My little black book is in my storage unit....1500 miles from here with my entire 412-dom.

There is much I can help you with and some things you need to measure.
Just like in the Haynes manual, you need to start stripping this thing down.

(1) with the trans horizontal.....remove the large round plug at the tail end. Inside you will see a ...15mm(?) nut. This is a VERY special nut. Do not destroy or lose it....or the "E" clip underneath. Take your old clutch disc and slip it onto the splined end of the main shaft and clamp a pair of vice grips onto the disc area...tight. This way you can hold the main shaft while you use a socket and ratchet to take the nut off the other end. Put the nut and "E" clip in a safe place. Pull tehshaft out from the clutch end. Put it someplace safe.

(2) In a place where you can contain residual oil...tip the tranny up vertical with the tail in the air. It will it flat and safe this way with the mainshaft out.
This may sound ugly...but the tail cone is so tedious to get put back onto the shift rods...and get it over the 8-10 studs sticking out at the same time....the best way I have found is to double nut each stud and remove it from the case. Make a patten on a cardboard box with the stud pattern....and put holes in each spot and stand the studs in the holes for the duration .

At this point.....the tail should pull off with minimal difficulty. Set it aside . there is not much to be done with it.

(3) at this point...you will be looking at the countershaft inset into the nd of the case and the three shift rods. Take an 8mm bolt...like a CV bolt andscrew in into the end of the shaft. Clamp vice grips onto the ounter shaft and tap lightly. It should pull right out. More to add in a minute....

[raygreenwood]

Ok...sorry for the delay. Most of the stripping down...you can get from the Haynes manual. Its pretty good....but there are things it does not tell you...like removing the studs on the tail housing.

(4) At this point you are looking at the tranny standing on end with no tail cone. Look at the end of it. You will see all of the internal ribs and the three shift rods sticking out.
You will also see...recesed...the counter shaft with an 8mm threaded hole in it. Take an 8mm bolt about 50-60mm long and screw it in. Clamp a pair of vice grips onto it.....AND...twist it clockwise.

What you are doing: If the counter shaft requires LESS than about 5-8 lbs to twist...meaning it twists easily ...like it could spin with too much force......you are going to haveto have the new shaft ground...to about .002" larger than this one so its a VERY slight interferene fit into the case when you re-install the new one. After this...with a mallet...tap on the vice grips to pull the shaft from the case.

Inspection of shaft:

CAUTION: At this point...if when you twist the shaft...it feels like there is gravel in it...or it won't twist all the way around....or...if when pulling it out it will not come out more than about 1/2".....AND....if the tranny had been howling for some number of miles.......you are screwed....partially.
What happens...is that the counter shaft needle bearings are poorly lubricated in this design ( I have initial partial solutions to this and am working on one that you might want to try). They wear out...and they wear a 20mm long groove all the way around the shaft at both ends.

Now....if the needles have fallen out of their cage...or shattered....(and in both of these cases you will only hear a moderate howl)...you can drive many thousands of miles on them with out any apparent shifting issues....(yet you are causing hideous damage)......these needles or parts of needles will permanently jam into the the groove ground in the counter shaft. It can never be removed. And...without removing this shaft...the tranny cannot ever be stripped further.
The only way is take a grinder and cut the transfer case to remove the shaft and counter gear cluster as a whole....therefore destroying the case. Been there...done that twice.

But...since this is a three piece case...you can take the entire main gear set, counter gear cluster, shims and transfer case casting from a tranny with say...a bad differential....and slap it right on.....so none of these are total junk unless both main gears and differential have died.

(5) with the counter shaft out...remove the plate on the bottom of the tranny. Take care not to misplace the green anodized long bolt. It is the lock bolt for the reverse idler gear shaft. Make note of where it goes.
To remove the cover plate screws....use a perfect fitting Philips screwdiver with a vise grips clamped on the shaft. I use a hand impact driver with correct "fat" bit and a light rap with a mallet.

(6) take a look at the cross shaft assembly inside. It has a large nut on each side of the tranny that holds it in. Remove them and it.

WAIT!...look close...there is a flat, bent idler lever on the side of the case on the inside...that actuates that cross shaft. It is assymetrical.....so mark which SIDE goes against the case...and which END goes UP towards the cover plate. DO NOT forget to do this...or it will get tedious.

WAIT!....the shaft that idler lever rides on....is an eccentric adjusting shaft. Unless you really want to adjust the reverse idler position from scratch......note the black metal cap on the outside of the tranny with two screws.....that holds this eccentric bolt. The outer end of the bolt is "splined"...and so is the cap that holds it.

Take a file or a dremel....mark which end of that cap is closest to the outer cover plate...I call that "up". Then carefully remove the two screws that hold it in....withdraw that cap....while pushing the eccentric shaft out from the inside. The object is to keep the splines of the shaft.....seated in the splines of the locking cap...so you do not lose the adjusting position. You can mark them better later. Take the cap with splined shaft intact..and wrap with tape or wire and put it aside. More coming up.

I am doing this in pieces because my poor laptop sometimes overheats and freezes in the middle of very long posts...losing them. Ray

[raygreenwood]

Next:

You are looking at the tranny...tail cone gone, counter shaft out...reverse idler cross shaft out and counter gear cluster pulled out. More on inspecting shaft and bearings later. BUT....DO NOT...lose the bronze shim from each end of the counter cluster. They are specific to each counter gear and case and have teh thickness inmm stamped on the back.

You now must remove the shift forks and detents to get the case off.

You will need:

You need a special socket...a 1/4" drive one. I believe it is either 8mm or 10mm....to remove the dog pointed bolt that holds the large shift fork onto its shaft. Its a "square" head bolt so you can check it with a small wrench to see the size. You will need a 12 point 1/4" socket to fit. In a rare pinch....you can use a strong wrench...attached to vice grips to remove this bolt.

Once the forks are off.....go to the side of the tranny...and remove the long black cap that covers the detents. Watch for the springs.
You will need 0-ring picks and a long thin magnetic pick-up.

With the tranny on its back...open lid facing up.....you remove the top detent plunger...and I think the second. In between each one....accessed from the top through the bore in the rib that contains the detents...from the plate side...is an 8mm acess hole. You will pull out the middle floating detent through this hole with a magnet.

At this point with the forks out...the detents and springs out, you can pull the shift rods from the case. Watch out...as there is a small 3mm detent plunger in one of the safts. Don't lose it.

Next.....look right at the end of the shaft by the big fat ball bearing. Look close...there is a very large snap ring holding the bearing into teh case. You can use a pair of hooked end o-ring picks or two small thin scredrivers to place under the hooked ends of the snap ring. Its not a hugely tense snap ring. Lever it out and pull it back

WAIT: make sure your gear slider rings where the forks were attched...are centered...not pushed fore or aft coupleing one gear or another. This is neutral. Not a big deal...but this is to keep any sliding dogs from popping out.

Now....stand the tranny up. Remove the 12 or so acorn nuts around the case. Lightly tapping on the case....WHILE....pushing down on the big fat bearing at the tail end...slip the case off the gear stack.

I say while pushing on the big bearing because......that gear section and sleeve bearing are not attched to the shaft. When you pull the case loose with teh snap ring intact....the bearing and synchro pull with it.

Thats ok....especially if you are having trouble with the snap ring.

At this point....you are looking at a unique and glorious thing. A differential case with a gear stack and pinion shaft two feet tall sticking up!
More in a minute.

[Bill K.]

First OFF: DO NOT at any time until we get there..remove a single part from the differential end. Since certain tools donot exist for this transmission....certain relationships must be measured as we take them off....and that comes last.


Ok....some things to know. My little black book is in my storage unit....1500 miles from here with my entire 412-dom.

There is much I can help you with and some things you need to measure.
Just like in the Haynes manual, you need to start stripping this thing down.

(1) with the trans horizontal.....remove the large round plug at the tail end. Inside you will see a ...15mm(?) nut. This is a VERY special nut. Do not destroy or lose it....or the "E" clip underneath. Take your old clutch disc and slip it onto the splined end of the main shaft and clamp a pair of vice grips onto the disc area...tight. This way you can hold the main shaft while you use a socket and ratchet to take the nut off the other end. Put the nut and "E" clip in a safe place. Pull tehshaft out from the clutch end. Put it someplace safe.

(2) In a place where you can contain residual oil...tip the tranny up vertical with the tail in the air. It will it flat and safe this way with the mainshaft out.
This may sound ugly...but the tail cone is so tedious to get put back onto the shift rods...and get it over the 8-10 studs sticking out at the same time....the best way I have found is to double nut each stud and remove it from the case. Make a patten on a cardboard box with the stud pattern....and put holes in each spot and stand the studs in the holes for the duration .

At this point.....the tail should pull off with minimal difficulty. Set it aside . there is not much to be done with it.

Good tip on the stud removal. Is that grease or sludge in the lower corner by the countershaft?

(3) at this point...you will be looking at the countershaft inset into the nd of the case and the three shift rods. Take an 8mm bolt...like a CV bolt andscrew in into the end of the shaft. Clamp vice grips onto the ounter shaft and tap lightly. It should pull right out. More to add in a minute....

Ok...sorry for the delay. Most of the stripping down...you can get from the Haynes manual. Its pretty good....but there are things it does not tell you...like removing the studs on the tail housing.

(4) At this point you are looking at the tranny standing on end with no tail cone. Look at the end of it. You will see all of the internal ribs and the three shift rods sticking out.
You will also see...recesed...the counter shaft with an 8mm threaded hole in it. Take an 8mm bolt about 50-60mm long and screw it in. Clamp a pair of vice grips onto it.....AND...twist it clockwise.

What you are doing: If the counter shaft requires LESS than about 5-8 lbs to twist...meaning it twists easily ...like it could spin with too much force......you are going to haveto have the new shaft ground...to about .002" larger than this one so its a VERY slight interferene fit into the case when you re-install the new one. After this...with a mallet...tap on the vice grips to pull the shaft from the case.

Mine would not turn at all until I pulled it out about an inch, then it turned with several pound. I used a socket to lever against the case like in Haynes and it worked good.

Inspection of shaft:

CAUTION: At this point...if when you twist the shaft...it feels like there is gravel in it...or it won't twist all the way around....or...if when pulling it out it will not come out more than about 1/2".....AND....if the tranny had been howling for some number of miles.......you are screwed....partially.
What happens...is that the counter shaft needle bearings are poorly lubricated in this design ( I have initial partial solutions to this and am working on one that you might want to try). They wear out...and they wear a 20mm long groove all the way around the shaft at both ends.

Now....if the needles have fallen out of their cage...or shattered....(and in both of these cases you will only hear a moderate howl)...you can drive many thousands of miles on them with out any apparent shifting issues....(yet you are causing hideous damage)......these needles or parts of needles will permanently jam into the the groove ground in the counter shaft. It can never be removed. And...without removing this shaft...the tranny cannot ever be stripped further.
The only way is take a grinder and cut the transfer case to remove the shaft and counter gear cluster as a whole....therefore destroying the case. Been there...done that twice.

But...since this is a three piece case...you can take the entire main gear set, counter gear cluster, shims and transfer case casting from a tranny with say...a bad differential....and slap it right on.....so none of these are total junk unless both main gears and differential have died.

I see what you mean about tendancy to wear a groove in the shaft. This one is in good shape for now, but I am willing to try your improvement for oiling.

(5) with the counter shaft out...remove the plate on the bottom of the tranny. Take care not to misplace the green anodized long bolt. It is the lock bolt for the reverse idler gear shaft. Make note of where it goes.
To remove the cover plate screws....use a perfect fitting Philips screwdiver with a vise grips clamped on the shaft. I use a hand impact driver with correct "fat" bit and a light rap with a mallet.

(6) take a look at the cross shaft assembly inside. It has a large nut on each side of the tranny that holds it in. Remove them and it.

WAIT!...look close...there is a flat, bent idler lever on the side of the case on the inside...that actuates that cross shaft. It is assymetrical.....so mark which SIDE goes against the case...and which END goes UP towards the cover plate. DO NOT forget to do this...or it will get tedious.

WAIT!....the shaft that idler lever rides on....is an eccentric adjusting shaft. Unless you really want to adjust the reverse idler position from scratch......note the black metal cap on the outside of the tranny with two screws.....that holds this eccentric bolt. The outer end of the bolt is "splined"...and so is the cap that holds it.

Take a file or a dremel....mark which end of that cap is closest to the outer cover plate...I call that "up". Then carefully remove the two screws that hold it in....withdraw that cap....while pushing the eccentric shaft out from the inside. The object is to keep the splines of the shaft.....seated in the splines of the locking cap...so you do not lose the adjusting position. You can mark them better later. Take the cap with splined shaft intact..and wrap with tape or wire and put it aside. More coming up.

I am doing this in pieces because my poor laptop sometimes overheats and freezes in the middle of very long posts...losing them. Ray

Cross shaft in place

Reverse idler

Reverse fork (looks assymetric also)

Pivot bolts loosened, cross shaft removed, reverse fork orientation taped

Front counter gear cluster end spacer

Front counter gear cluster end spacer seat in case

Rear counter gear cluster end spacer

Rear counter gear cluster end spacer seat in case

Reverse idler lever

Reverse idler cover plate marked (bottom)

Reverse idler cover plate removal

Reverse idler lever marked (away from case, bottom)

Reverse idler assembly still indexed

Next:

You are looking at the tranny...tail cone gone, counter shaft out...reverse idler cross shaft out and counter gear cluster pulled out. More on inspecting shaft and bearings later. BUT....DO NOT...lose the bronze shim from each end of the counter cluster. They are specific to each counter gear and case and have teh thickness inmm stamped on the back.

You now must remove the shift forks and detents to get the case off.

You will need:

You need a special socket...a 1/4" drive one. I believe it is either 8mm or 10mm....to remove the dog pointed bolt that holds the large shift fork onto its shaft. Its a "square" head bolt so you can check it with a small wrench to see the size. You will need a 12 point 1/4" socket to fit. In a rare pinch....you can use a strong wrench...attached to vice grips to remove this bolt.

Once the forks are off.....go to the side of the tranny...and remove the long black cap that covers the detents. Watch for the springs.
You will need 0-ring picks and a long thin magnetic pick-up.

With the tranny on its back...open lid facing up.....you remove the top detent plunger...and I think the second. In between each one....accessed from the top through the bore in the rib that contains the detents...from the plate side...is an 8mm acess hole. You will pull out the middle floating detent through this hole with a magnet.

At this point with the forks out...the detents and springs out, you can pull the shift rods from the case. Watch out...as there is a small 3mm detent plunger in one of the safts. Don't lose it.

Detent plate removal

Detents and springs removed

Reverse shift rod c-clip removed and rod removed

3rd/4th shift fork square head bolt removed (use 9mm socket)

3rd/4th shift fork detent

Shift forks re-assembled for storage ('mid' is 3rd/4th; 'top' is 1st/2nd)

Next.....look right at the end of the shaft by the big fat ball bearing. Look close...there is a very large snap ring holding the bearing into teh case. You can use a pair of hooked end o-ring picks or two small thin scredrivers to place under the hooked ends of the snap ring. Its not a hugely tense snap ring. Lever it out and pull it back

Could not remove this snap ring...

WAIT: make sure your gear slider rings where the forks were attched...are centered...not pushed fore or aft coupleing one gear or another. This is neutral. Not a big deal...but this is to keep any sliding dogs from popping out.

I didn't get this part, these must be the slide dogs

Now....stand the tranny up. Remove the 12 or so acorn nuts around the case. Lightly tapping on the case....WHILE....pushing down on the big fat bearing at the tail end...slip the case off the gear stack.

I say while pushing on the big bearing because......that gear section and sleeve bearing are not attched to the shaft. When you pull the case loose with teh snap ring intact....the bearing and synchro pull with it.

Thats ok....especially if you are having trouble with the snap ring.

At this point....you are looking at a unique and glorious thing. A differential case with a gear stack and pinion shaft two feet tall sticking up!
More in a minute.

Used reverse shaft pivot bolt heads and final drive case studs as lever points to lift gear box off diff case using screwdriver - did not push on big bearing, snap ring still on

[raygreenwood]

Ok:
Some things the book does not tell you

Looking at this stack of gears, synchro hubs and sliders.....as the book notes....one of these "sliders" (the ring type parts that the forks fit into) has a grove machined around one flange. Its purpose was to correctly orient that ring in the right direction. Problem I have found is that both sliders should be correctly oriented...and sometimes neither is marked.

So...before unstacking and removing the gears....use the dremel tool...to carefully mark the side of each sslider toward the tail cone (which is "forward)

WAIT: Also...the position of each slider ring...relative to each synchro hub should be maintained...so mark them relative to a mark put into each synchro hub...in the center area...not on any of the splined faces....
AND...the synchro rings must be marked relative to each synchro hub and slider....to maintain correct relationships.

As you disassemble...lay all parts out horizontally on a large piece of newspaper or towel...in order as they come off.

When you pull off the big bearing...watch out...there is a bearing inside.

By the way...these and the countershaft bearings are the only ones I have found...and generally all that are needed to be replaced. They are standard metric sized needle bearinsg and can be matched up at any reputable bearing dealer. If you canot find the correct long needle bearing to fit inside of the bearing hub...you can use two half length one stacked. these are readily available.

When you get the top bearing, hub and synchro off...they just lift off...you will see athree armed snap ring retainer in the synchro hub. Lift it of to reuse. It is a type 1 part...so it is replaceable.

Under it is a snap ring. Take it off carefully. Its thickness is specific. At a later point if it is found that this snap ring fits too loose due to wear...leaving the gear stack loose....you can buy a thicker one and sand it down.

After this snap ring comes off...evrything simply slips of the stack. Lay them out. Clean them carefully later.

You can get all the way down to just the differential casing.....with that huge mainshaft/pinion shaft sticking out.

The hardest and most dangerous part...is removing the large aluminum centering ring for the pinion shaft. Just like the book says....

Its tough to find a 10+ inch two arm puller to fit into the recesses at the side of the ring. I use a combination of blocks of wood and hefty levering tools and screwdrivers....the wood so I don't lever against the case....and some heat and oil...to work my way around this aluminum disc...slowly levering it up until it pops loose.

Make DAMN sure you do not crack this part or you are toast!

Once that is out...we can start disassembling the differential. Ray

[Bill K.]

Ok:
Some things the book does not tell you

Looking at this stack of gears, synchro hubs and sliders.....as the book notes....one of these "sliders" (the ring type parts that the forks fit into) has a grove machined around one flange. Its purpose was to correctly orient that ring in the right direction. Problem I have found is that both sliders should be correctly oriented...and sometimes neither is marked.

So...before unstacking and removing the gears....use the dremel tool...to carefully mark the side of each sslider toward the tail cone (which is "forward)

Gear stack with factory mark on top flange of lower slider, but no mark on top slider

WAIT: Also...the position of each slider ring...relative to each synchro hub should be maintained...so mark them relative to a mark put into each synchro hub...in the center area...not on any of the splined faces....
AND...the synchro rings must be marked relative to each synchro hub and slider....to maintain correct relationships.

Top slider ring marked on top flange and to align with brass synchro (synchro marked upon removal)

Inner slider hub marked also

Other synchro marked

As you disassemble...lay all parts out horizontally on a large piece of newspaper or towel...in order as they come off.

When you pull off the big bearing...watch out...there is a bearing inside.

By the way...these and the countershaft bearings are the only ones I have found...and generally all that are needed to be replaced. They are standard metric sized needle bearinsg and can be matched up at any reputable bearing dealer. If you canot find the correct long needle bearing to fit inside of the bearing hub...you can use two half length one stacked. these are readily available.

When you get the top bearing, hub and synchro off...they just lift off...you will see athree armed snap ring retainer in the synchro hub. Lift it of to reuse. It is a type 1 part...so it is replaceable.

Under it is a snap ring. Take it off carefully. Its thickness is specific. At a later point if it is found that this snap ring fits too loose due to wear...leaving the gear stack loose....you can buy a thicker one and sand it down.

Retainer removed

Snap ring removed

After this snap ring comes off...evrything simply slips of the stack. Lay them out. Clean them carefully later.

You can get all the way down to just the differential casing.....with that huge mainshaft/pinion shaft sticking out.

Removing gear stack involved creative work with screwdrivers, drifts, heat, and hammers...

The hardest and most dangerous part...is removing the large aluminum centering ring for the pinion shaft. Just like the book says....

Its tough to find a 10+ inch two arm puller to fit into the recesses at the side of the ring. I use a combination of blocks of wood and hefty levering tools and screwdrivers....the wood so I don't lever against the case....and some heat and oil...to work my way around this aluminum disc...slowly levering it up until it pops loose.

Make DAMN sure you do not crack this part or you are toast!

Once that is out...we can start disassembling the differential. Ray

Fiberglass hammer handle modified to lever centering ring off using BFH and heat

[raygreenwood]

I have a class to go to or else I would give more this morning. It will be 6:00 Eastern time.

The book to have handy if you have it is the Brown Bentley type 3 book.

Before we get ito teh differeential...we will do some serious talking about gears, bearing, synchros and the countershaft and its bearings.....and ways to oil it properly. Ray

[raygreenwood]

OK.... ...You are down to the differential.

One of the hardest parts is to get that aluminum centering ring ooff of the mainshaft without cracking it. First....you will notice a thin snap ring around the base. Use a pair of stiff 0-ring picks.....or a pair of thin screwdrivers to take it loose.

Now....DO NOT...pry in the two slots that are in the edge of the ring taht are for a puller. These are even dangerous to use with a puller. They are too far out on the edge from the center where the ring is mounted. It flexed the ring and its the only way I have cracked one. The best way I have found...is to use two extremely hard pieces of wood or fiberglass....like hammer handles . Slip them under the edges of the ring .....and lever against the differential case.
I use a some heat from a propane torch....on the edges of the ring so as not to prematurely heat and expand the shaft.

Once that ring is off:

A few points here before we start on the differential. If you read through the Bentley type 3 manual....in the section for the automatic
not the manual.....and while looking carefully at the differential design of the 004....you will soon see that they are the same full hypoid design....with the same problems. The case is in the way of measureing what you need to measure.....without very special tools.

Do not despair....its not that hard. Just have to get creative. A few things...just like on the differential of the type 003 autobox....are very fortunate.

(1) You can now see...the cast iron pinion carrier. It fits into the case...from the bell housing side if memory serves. It has an adjuster ring in the end...which you can see....and couped with the shim that is under the five bolt carrier inside of the bell housing....will always set the pinion mesh depth to the correct center measurement to the ring gear.



As long as you keep....this ring, pinion gear, main shaft and differential housing, and nose cone seal from the bell housing.... together....with that thick shim with the five bolt holes.....you will never have to adjust the pinion gear to ring gear mesh depth.

The only thing you will have to set....is the bearing preload on the pinion shaft.

(2) At this point....you will be loosening the two differntial side gear aluminum adjustin rings. Before you start.....mark them permanently ...LEFT AND RIGHT. Then....with a sharp, fine punch...mark a 12:00 position both on the ring and on the case. Be very exact about this.

Now....start unscrewing them. Count each turn out...and WRITE IT DOWN. You will always get to a point where the ring comes out.....at less than a final full turn. At the exact point the final thread becomes disengaged....use a dremel or a file....to put a line mark....right at the punch mark.
In this way...each full revolution is from punch mark to punch mark. The final partial turn...is punch mark to line. So when you start turning this back in.....you start with the file line at the punch mark.

Since you will be using new bearings and setting the preload...ao you will probably not be using the old adjustment....but this is a safety precaution in case you have to reassemble it the way it is.

Let me save this and start on a new parargraph.

[raygreenwood]

Now...with the adjusting rings out....you will notice that you cannot remove the differential until the pinion shaft and pinion carrier come out.

For this.....you need to strap the case down horizontal. Take a socket, extension and breaker bar...and crack loose the five nuts inside of the bell housing that hold the pinion carrier. You will notcie that when th ebolts are gone...the pinion carrier does not yet budge.

With the tranny sitting horizontal.....slave cylinder hole at the top....like right side up.....look at the bottom...or lower edge of that cast iron flange inside of the bell housing that you just took the five nuts off of. You will notice a ledge...or lug area. With a small "hook" end prybar like a nail puller...levered under that ledge....you will break the cast iron nose cone loose. It will fall out......and in it is the bearing race for the pinion bearing. You use that same pry bar to lever that race out.

Now you can push the pinion carrier and shaft out from the inside.

Make serious note here:

When you buy new pinion bearings...do not do so until you have the old ones off. You will need to do this in a press with proper pullers at a shop.

The reason is.....and I made this mistake.....the bearing that is on the pinion shaft is available in TWO identical part #'s...with different letter codes. The different letter codes denote a different filet radius on the bottom side of the bearing. One works...the other does not.
DO NOT buy bearings until you have the bearing off to read the EXACT part #.

Before you take the adjusting ring out of the pinion carrier you will need to use the dremel to remove the blockage from the factory locking punch mark. If you do not...you will distort the threads on the ring and it gets ugly. Just like the side adjuster rings.....make a punch mark at 12:00...turn until it disengages...and at the final thread....make a line at the punch mark so you have a strting place.

You can now pull the shaft out of the carrier enough to get a puller under that bearing....if memory serves.

Do the bearings on the pinion shaft first. You can pull out the differential now.

NOTE:...when you pulled out the aluminum side adjuster rings on teh differential...there should have been a split steel ring spacer on the side shafts on each side...under the seal. They are specific to each side unless they are the exact same thickness. There is some explaining to do about these spacer rings ....I will get to when we talk about the differential and spyder gears. More later...Ray

[Bill K.]

Thank you Ray. I'll edit my posts in this topic with added pictures and comments as we go.

[Bill K.]

Before we get ito teh differeential...we will do some serious talking about gears, bearing, synchros and the countershaft and its bearings.....and ways to oil it properly. Ray

Please do...

[raygreenwood]

Ok......The snap ring that holds the bearing into the case...is visible in the 15th picture of your newest post.

The snap ring with the holes in the end that you cay you cannot get out......does NOT....belong in this transmission .

By this finding, I know that someone has been into this box. But what they have done is not a bad thing.

Your countershaft is shot. Not that it looks bad.....but it really is. The problem is that the countershafts are only lightly case hardened. Any marring of teh surface ....not only is almost through the case hardening....it mars the needles. You will find the same "marring" inside of the bores of the counter gear cluster where the needles ride.

You will not be able to resurface that area. But what you can do is one of two things (a) you will be able to buy full enclosed cartridge style needle bearings that have an outer shell/race. They look just like big versions of the idler bearing in the crank shaft back near your clutch.

The only ones available are about 23mm shorter in length....but do just fine. In this way....if you have a new countershaft made...and replace the original needles with cartridge needles....you are done with thd counter shaft.

The new countershafts I have made from already hardenened 18mm shaft. You can buy a 36" length finished....for about $40-60. Then....take it to a machine shope with a drawn out plane. Then shoud be able to grind the step in the bottom end...and then with a carbide bit...drill the hole in the end because the shafts ae not hardened all the way through.

(b) New method of doing these bearings. This one will work....I know this....but you will need some faith to try it.
Consider not putting needle bearings back in at all.

The problem with this counter shaft is that there is a single small hole in the center of the counter gear cluster for oil. There is no real flow through for the oil to get out past the shims at the end. The hole in the gear is small enough that the viscoisty of the oil in cold weather will not flow through it readily. Cars that drive in cold weather heavily get worn countershaft needles faster.

You can make solid bearings to press into the end of the gear in place of the needle bearings.....made of Torlon 4301 bearing grade polyamide/imide plastice. It is harder than delrin.....good to close to 600F constant and chemically inert. It is made for making these kind of bearings. It machines like butter....can be polished....and a one foot rod of it will cost about $60 depending on the diameter.

What I am suggesting....is making not only small cylinders of this to replace both needle bearings......but with extended bottom tubes to slip into each end of the counter gear....and reach almost all the way to the center of the gear. Then.....slot the thin inner tubes that reach the length of the shaft....and groove the insides........so it acts as an auger as the counter gear spins past the fins......augering oil up through the center like a pump....and giving roughly ten times the bearing area to the whole counter shaft.

By tommorrow night I will e-mail a sketch of this part and it will become more clear. Ray

[Bill K.]

I'll get some chromoly rod and Torlon and look forward to your sketches. Thanks!

[raygreenwood]

Ok...DO NOT use chromolly for the shaft. It is very tough and has high tensile strength....but unless you send it out to have it hardened....its surface hardness is too soft. In most cities...it is not too hard to get something hardened. But...between "decarberizing"...and teh fact that every different stel takes a "cast" (meaning it curves numerous thousandths along its length)......its too much of a hassle.

Or...maybe its not a big deal....depending on what we use for bearings.

Let me explain. The stock shaft is very hard on its surface. It must be just slightly less hard than the needle bearing. Its got to stand up to teh bearing. But....the thickness of the hardening on tehstock shaft is very thin. By case hardening the surface they could keep it very straight. The harder you harden it...or the deeper you harden it....the less straight it stays.

This is assuming you put needle bearings back on it. In that case...look in the Mcmaster Carr catalog. You can buy very high tolerance lengths of metric shaft....that are made for linear bearing use. They are polished to almost the level you need...and are very hard. In fact all of the shafting in teh last two yeasr for variosu uses that I have bought from mcmaster....have been hardened almost twice as deep as they advertized. And...they are very straight..

But....if you use Torlon bearings.....this hardness will make no diffference. You can use tool steel or chromolly.

The Torlon......be careful which one you buy. Check teh # I gave you. There is more than one. You need...either bearing grade (compared to electrical grade)...or glass filled bearing grade...either one. The stnadrad bearing grade frinishes out smoother.

I forgot to mention....this torlon has a coefficent of friction very close to ....teflon. I have made over 300 bearings from this material ...to replace cam foller type bearings in printing equipment in the last year. All of them had at least 60 lbs of load on them...and ran non lubricated....and had no failures. They replaced needle bearing versions of cam followers from 16mm to 25mm in diameter. Awesome stuff. It will work in place of the needle bearings no problem.

You need to make it with an ID about .001-.0015 larger than the 18mmshaft so it can have oil. We will groove it with dremel or hacksaw. Since it is tough...but will never be harder than the shaft....the shaft does not need to be hardened.

To solve the oiling issue.....you need to make grooves...first cut with a file....3 of them....120* apartt...on the faces of each end of the counter shaft gear cluster where it contacts the spacers shims...then polish them with a dremel and gray soft wheel...and then 2000 grit sandpaper. This allows oil...that goes into the only oil hole in the center of the counter gear cluster...to flow through and out the new grooves at the end. This works very well. We then...as a tube later to the vent hole ....so we can add an extra quart of oil to keep it all submerged...and flooded.

The OD of the torlon bearing.....should be maybe .002 interference fit to the inside of the counter gear cluster so it rotates with the gear cluster. I also think you can add a locator pin with no problem in the step in the counter cluster. The Torlon will work great. More tommorrow. Ray