Datsun Roadster Forum-311s.org

yusef wrote: ↑Fri Aug 21, 2020 6:10 pm Thanks for the info Joe.

My box is a warner (brass) synro rings. Does this thrust washer still apply? Reverse felt fine yesterday, but was reluctant to drive it any further in case of catastrophic failure. Engine and tranny are out today.

Is the rear nut, and possible culprit the one in the attached pic circled in red? This is a pic of my tranny when it was partially disassembled at the shop.

Also, I could shift into fifth gear, but would not stay in place unless I held it there. Also, didn't matter what RPM, would not stay in fifth.

Thanks.

Thrust washer is same on warner box. That is the main shaft nut you circled and the thrust washer is inside the circle too - so it's there. Note the dimples on the lock nut - that's an attempt to deform the threads with a punch to help keep it in place. Also, the extra threads behind the lock nut implies to me that there should be a second lock nut. Some of the nuts have a collar that is used for the dimples to help keep it in place (see pic in link: https://cdn3.volusion.com/ymcqg.kvqok/v ... 1549560633). I also use red loc-tite. I figure if I have to rebuild it again, I can put the heat on it to get it off.

Regarding your Z expert - From your pic - You should never clamp the center plate in a vise without a pad as it can deform the sealing surface of the plate, where the gasket goes. See the green rubber magnetic pads in my pic below

What Bill refers to is the selector spring that pushes a steel ball into the shift fork detent. it also provides driver feedback on the shifter that you are shifting into a new gear "a gate". Do you feel the gate? It's easy to check as Bill stated. In you pic, it the lower hole in the center plate. It will have a bolt in it...in order of removal, bolt, spring, ball. Here's a pic of a servo box, I circled the detent and the bolt

I do feel the gate when shifting.

If I unscrew the fastener will the ball and spring just fall out and I can just put them back in the same way?

Thanks.

You might need a magnet to get them out and yes, just put back in same way. Magnet will keep the parts together. Ball is pretty small - like a 1/4 "

Have the transmission in neutral

Yosef,

Sound like the original problem you brought the car into the shop for wasn't fixed. Inspect your pilot throw out bearing while the engine/trans is out of the car.

I agree with Bill and Joe, regarding the detent, After experiencing the shop's workmanship, I would verify that all 3 are in the correct spots. I might also try to find someone local to you, that would give it a quick once over for a small fee. I lost 5th recently in my servo trans, and thank god I had purchased a spare trans from Dynaguy. Parts for that style are extremely expensive, but I was able to get synchros from my spare, and a couple better gears. I agree with Dan, regarding the noise. Once you push the clutch in, the transmission is out of the loop. Easiest diagnosis ever. Pat

Okay, I confirmed the the ball and spring are in place.

I want to remove the tail section now to check on the mainshaft nut in the event it did back out. Is this just a simple remove castlenut (how do hold the mainshaft in place to un-torque this castle nut), remove speedo nut, remove fasteners at center place, and slide tail section off?

Thanks,
Joseph

In my experience there is no "slide the tailpiece off". For me it has been more of a press fit, so I needed lots of room around to be able to gently persuade the tail piece off with soft blow methods. The aluminum will dent easily and then will leak like a sieve. In my opinion, there is no way to do this in the car, it must come out.

Yes, I have engine and tranny out. So the trick to getting tail section off is slow and steady?

Find someone, pay something to have them look it over, then don't worry anymore. I don't know where you are, but I'm sure you'll get a message from someone willing to help you out. Unless you know transmissions, you are shooting in the dark. I am lucky I knew someone that knows these transmissions(thanks Dave!) and didn't have to pay a shop. After seeing all of the reasons one part is better than another, I will still never attempt to rebuild one myself. No disrespect intended, but how much fun was it to pull the motor/trans? Pat

If it is out, then yes, slow and steady is the way to go. I had never done a transmission before I tackled mine, and I jumped right in. The Scheeler book is good, (it does have one or two mistakes in the transmission section, but I can't remember them now ) but even so I got hung up a few times and came to the forum for help - "23 yr rebuild" was an immense help among others.
I consider myself fairly mechanically advanced, and adventurous so I was not afraid to jump in. I leaned a lot, and it was fun. And it is not too tough once you see it and figure it out. Again, this will 100% depend on your aptitude and confidence level.
There are some specialty tools required, so be aware - I needed some large bearing pullers, a press, and a really big wrench to get the torque required on that bolt. I searched for a long time to find something big enough - luckily, JT has a perfect and cost effective tool for this.
If you are hesitant, seek a professional, if you are resourceful and patient, I think it can be tackled.

Okay, I'm trying to remove the tail section now. All fasteners and relevant connections are out, but that sucker is stuck on there. One of the tabs on tail section is missing. Z-experts used a boatload of RTV. I'll keep trying. Thanks for the tips all.

Apply a lot of heat to the tail housing at the bearing interface behind the seal. Take the seal out first. The bearing is press fit into the tail housing, get the housing hot and then try tapping the housing off using the ear. Do not pry on the sealing surface/center plate

Make sure the control rod is disconnected

Since you have the transmission out, unbolt it from the engine, Pull the clutch plate and replace the pilot bushing in the crank. It’s likely the cause of the whine.

Okay, I was able to to pull the tail end. Thanks for the advice, Joe.

Attached are photos of what I'm seeing. Seems like the double-nut is in tact so that doesn't explain the 5th gear popping out issue...

I don't have the right size wrenches, so I'll get some to verify the torque.

Let's clarify the situation. You took your car in, for a noise that went away when you put in the clutch. You drove your car after a repair, and it wouldn't stay in 5th gear. Is that right? The initial noise is most likely your throw out bearing. The not staying in gear is most likely your detents, either wrong/missing springs, or somethin related. If you had no 5th gear, like a neutral, you would have a slipping non-splined 5th.Could you hold it in 5th? What exactly were your symptoms in 5th gear? I experienced this a month ago, and it also affects reverse. Pat

Hi Pat,

Let me back up.
1. I took the car in to diagnose and repair a whine coming from my transmission. I push in the clutch (pedal to floor) and sound goes away. Slowly release clutch, sound reappears and will get louder if reving engine. This made me think it was the main input shaft bearing.
2. Take the car to z-expert to get this resolved.
3. 2 months later, z-expert lets me know they cant figure out what's wrong and the sound is still there.
4. I go pick up the car, sound is certainly still there.
5. Drive home, and 5th gear pops out of gear and goes into neutral (literally, the shifter moves from 5th to neutral). I can hold the shifter in 5th physically with my hand, but otherwise, it pops out every time. This is a new issue for me. I had the 5th gear replaced 2 years ago with one from Dean.

Thanks.