Transmission Disassembly Help

[Stoffregen Motorsports]

Are you sure there's not a clip holding that hub on?

[Poptartjake]

1 hour ago, Stoffregen Motorsports said:

Are you sure there's not a clip holding that hub on?

Idk. There is a snap ring on the smallest of the 3 shafts that still has a single gear on it, but I don't think it needs to be removed (nor can I get the thick ass snap ring off). I've been pounding away at it slowly this morning and this is where I've gotten to. The input shaft feels like it's about to come out, but I'm not sure how much more forward it needs before fully disconnecting. 

 

[bottomwatcher]

I have no useful input on this, but I have been following. You have the patience of a saint! 

[Stoffregen Motorsports]

I do know those shift collar hubs can be very tight on the shaft. My previous comment about "if you have to hit it with a hammer"... it comes from having to hit it hard with a real hammer. but isolate the shaft you're hitting with a thick piece of aluminum or brass/bronze, something soft that will still transfer the energy.

 

If it feels like it's stuck, it may well be stuck and forging onward may be a fools errand. I'm not there so it's ultimately your call.

[Poptartjake]

14 hours ago, bottomwatcher said:

I have no useful input on this, but I have been following. You have the patience of a saint! 

Thanks! I look at this all as a big learning experience, so patience are a must. Still better than any school!

 

12 hours ago, Stoffregen Motorsports said:

I do know those shift collar hubs can be very tight on the shaft. My previous comment about "if you have to hit it with a hammer"... it comes from having to hit it hard with a real hammer. but isolate the shaft you're hitting with a thick piece of aluminum or brass/bronze, something soft that will still transfer the energy.

 

If it feels like it's stuck, it may well be stuck and forging onward may be a fools errand. I'm not there so it's ultimately your call.

I mean, it doesn't feel stuck? I can free spin the input shaft and the piece attached to it, it just doesn't have enough room to slide out yet, it seems. I'll try some more today and if nothing else, I can start hunting pull-a-part yards. Maybe I'll check one out today. Parts to repair this trans are gonna be about the same as pulling one from a yard.

Edited August 10, 2020 by Poptartjake

[Poptartjake]

Today I've learned what it would have been like to build the railroads.. But no, seriously, I've been beating on the two shafts, but have only opened up another few millimetres worth of gap.
From what I've seen as I've beat on it, I have to hit the input shaft, then the counter shaft, rinse and repeat as the gears on the counter shaft hit the input shaft, preventing it from moving further on its own.
  

Edited August 10, 2020 by Poptartjake

[Poptartjake]

Pretty sure I'm being a dumbass and need to remove the synchro hub (even though the FSM says otherwise). I do not have a long reach gear puller, though, so I guess I'll need to buy one of them.

Also, the more I've been learning and looking at the internals, I've started noticing it's more damaged than I thought (chipped teeth, mainly), but should still reassemble and drive okay. I don't plan for it to last too long, and this whole process was mostly for a case study in how to fix a transmission, which it has been. But it would have been cheaper/easier to find a junkyard replacement. 🤪

Edited August 10, 2020 by Poptartjake

[datzenmike]

 

Bottom right is the counter driven gear. You can see there is a C clip in front of it. Did you remove it?

[Poptartjake]

2 minutes ago, datzenmike said:

 

Bottom right is the counter driven gear. You can see there is a C clip in front of it. Did you remove it?

Yes, I'm not trying to remove the counter gears. I'm trying to remove the entire shaft (not really remove, but loosen enough for input shaft removal). 
I've come to realize the synchro hub on the rear half of the input shaft needs to come off, but I don't have a means of doing so right now. 

[Poptartjake]

Here's a pic of the entire guts in their current state (ignore the PB Blaster around the counter shaft 😆)

Edited August 10, 2020 by Poptartjake

[datzenmike]

You only need to pull the very front gear off the counter shaft. It's on a keyway. I pulled the input shaft off by removing just the counter driven gear

 

Counter is at top. The gear with the snap ring in front of it is driven by the input shaft above it. The one that is damaged in yours.

 

It was a while ago but once the counter driven gear is off the main input shaft comes off.

 

Input shaft on far right

 

I still have it...

 

So I was asking is there a snap ring on the front of the counter driven gear???

 

 

 

[Poptartjake]

It's already off. The counter gear itself is completely stuck, which is why I've had to resort to my current methods. I've tried heating it up, but it won't budge from the counter shaft. 

Also, I've somehow managed to seize up the threading on my 3 jaw puller, so ya....

Edited August 10, 2020 by Poptartjake

[datzenmike]

As I said if the counter gear is off the input is free to come off. I'm damned sure I didn't take the transmission apart.

[Poptartjake]

Just now, datzenmike said:

As I said if the counter gear is off the input is free to come off. I'm damned sure I didn't take the transmission apart.

COUNTER GEAR IS STUCK.

[bottomwatcher]

71c Hardbody or Frontier? The old weak B is what the 720 crowd is used to dealing with although not that much different from the C. I went through 4Bs and have been running a C 15 years no issues. I have a spare c sitting on the shop floor I picked up for $100 from a buddy with a junkyard ( I had to pull it). The Cs are cheap and plentiful. Let this one go for all our sakes. This was painful to observe but like I said. You gots some patience!

[Poptartjake]

3 minutes ago, bottomwatcher said:

71c Hardbody or Frontier? The old weak B is what the 720 crowd is used to dealing with although not that much different from the C. I went through 4Bs and have been running a C 15 years no issues. I have a spare c sitting on the shop floor I picked up for $100 from a buddy with a junkyard ( I had to pull it). The Cs are cheap and plentiful. Let this one go for all our sakes. This was painful to observe but like I said. You gots some patience!

I'm this far in, giving up feels stupid. I will beat this thing. And then properly kill it with power.

Edited August 11, 2020 by Poptartjake

[datzenmike]

2 hours ago, Poptartjake said:

COUNTER GEAR IS STUCK.

 

Yes the counter is stuck. I'm referring to the removable gear on the front of the counter. The picture shows a snap ring? C clip? do you have it removed?

[Poptartjake]

Da fuck is this metal dowel? It's preventing me from removing the synchro hub off the back...

Edited August 11, 2020 by Poptartjake

[Poptartjake]

I win. Also, recommendations on cleaning things up without full disassembly? Can I just flush it with 1 or 2 things of fresh gear oil after it's back together? 

Edited August 15, 2020 by Poptartjake

[Draker]

You cut it off? How do you plan to get it back together?

[NC85ST]

Those gears weren’t necessary anyway, right?😳

[datzenmike]

11 hours ago, Draker said:

You cut it off? How do you plan to get it back together?

 

Cut what off???

[Poptartjake]

12 hours ago, Draker said:

You cut it off? How do you plan to get it back together?

Wait, you mean I can't cut a new input shaft back on? 
Honestly, not 100% sure what my plan is, but we'll cross that road when the new input shaft arrives. And yes, I did count the gear teeth to make sure I ordered the right one (22/31).
 

1 hour ago, NC85ST said:

Those gears weren’t necessary anyway, right?😳

Na, input shaft was torched anyways and I needed a little extra clearance to slide it off.

 

59 minutes ago, datzenmike said:

 

Cut what off???

Input shaft teeth so I had enough room to slide it past the counter drive gear.

[Stoffregen Motorsports]

On 8/10/2020 at 7:22 PM, Poptartjake said:

Da fuck is this metal dowel? It's preventing me from removing the synchro hub off the back...

Yep, that will keep you from removing the countershaft. You need to hit the sleeve forward so you can pull that pin out, then everything should slide out.

 

Honestly, I have never seen this dowel pin before. I've rebuilt dozens upon dozens of Datsun transmissions, but the newest Datsun trans I ever had apart was from a 280zx, and that was a while ago. Obviously things have changed, so I apologize if I urged you on without all the facts.

[Poptartjake]

22 minutes ago, Stoffregen Motorsports said:

Yep, that will keep you from removing the countershaft. You need to hit the sleeve forward so you can pull that pin out, then everything should slide out.

 

Honestly, I have never seen this dowel pin before. I've rebuilt dozens upon dozens of Datsun transmissions, but the newest Datsun trans I ever had apart was from a 280zx, and that was a while ago. Obviously things have changed, so I apologize if I urged you on without all the facts.

Ya, I spoke with someone else who explained the sleeve and dowel situation, but I couldn't get the sleeve to budge, so I cut the gears off the input shaft and removed it that way. Now, I need to get the counter shaft forward a bit more before the new input shaft arrives so I will have enough room to clear the counter gear.