1931 Nash transmission

[31nash880]

First, thanks to everyone who has helped with this car so far. Getting into maintance items for the winter. Have thread under restorations.

Anyhow, Got floor out of the way for cleaning and general maintenance of brakes and running gear. Not much info I have found on these cars.

Questions:

Hopefully you can see the nub coming out of top rt side of tyranny. Looks like it use to be made of conduit and went somewhere. What is it? Lower cable is speedometer. 

What is the thing on driveshaft?

What is thing on exhaust pipe?

Hope to learn.

Thanks again to all and Happy New Year.

[chistech]

I can help you with the drive shaft question. There is a u joint in that housing. The spring on the shaft keeps the cover tight to prevent grease leakage. There should be a 1/8” pipe threaded hole in that cover with a small flat head screw plug. Through the years many of these plugs were replaced with zerk fittings but that is wrong to do as it throws off drive shaft balance. The drive shaft on my 32 olds is virtually identical. The nash and olds seem to share technology during the early thirties.
     On the exhaust pipe. That’s the exhaust bearing!😂 Sorry, i really don’t know what it is but it looks just like a bearings with a lock ring to hold it on. I will say on the serious side is 32 Olds used a isolation mount for the muffler that used two offset grommets in a special bracket. What you’re showing might be Nash’s version of a rubber isolation mount. I see what appears to be some screws on a flange on the muffler side. That mount might connect on the flange but isolate the muffler end from the chassis mount with that bearing looking thing.

     Usually a second transmission cable on a 32 car went to the free wheeling mechanism. A bad feature that only lasted into a few 33 cars at the beginning of production. I don’t know if nash had a free wheeling option in 31 but some nash owners should be able to help you out. Try the Nash club. I included a picture of my driveshaft and the olds factory muffler isolation mount.

[31nash880]

Thank you, this is my first pre war car. Expected to hot rod it but it is to original and in great condition to do that. That means a great deal of learning. That and being a Nash is a challenge. Not many in Nash club deal with the old ones.

Still trying to understand this free wheeling thing. Was hoping for disconnected overdrive. Seems to top out at about 40. Seems it should go a bit faster.

On the driveshaft u joint, should I lube it? Car sat up to 50 years.

[JFranklin]

58 minutes ago, 31nash880 said:

Seems it should go a bit faster.

On the driveshaft u joint, should I lube it? Car sat up to 50 years.

Think 50 MPH on the high side. You should clean and lube everything before any use the first time and then lube as the manual covers.

[Lahti35]

The u-joint DOES need greasing. You can see the 1925 version on my Nash...

 

The cap slides around on the cover and keeps grease in via a graphite seal...

 

I'm not sure how the later ones grease but the earlier ones are greased through a fitting on the driveshaft that feeds the u-joint. It greases the entire inside of the housing where it then works it's way into the joint, very important to make sure the housing is packed full. If you don't see a grease fitting on the housing then look on the driveshaft...

 

The muffler has bunch of spacers installed by an exhaust shop to make an off the shelf muffler fit. I had some of these on my '25, you have many on your '31! The little tabs give them away, a muffler with the right ID on the input would eliminate those. They do no harm in your case, I got ride of mine 2 weeks ago when I swapped my muffler out. 

[Lahti35]

1 hour ago, JFranklin said:

Think 50 MPH on the high side. You should clean and lube everything before any use the first time and then lube as the manual covers.

This is correct, you will need to take it apart and clean it. Mine was full of hardened grease and did not move smoothly. I let mine sit in a solvent tank for 24 hours to soften the goo in the joint itself and flush it out. I sprayed mine with PB blaster and reassembled in preparation for greasing once installed back on my car. 

 

Your u-joint is most likely this one from the 1931 Nash 6 parts book... They made some changes after '25, the one pictured above from my car.

[Lahti35]

Is this the nub you're talking about? 

 

I believe that is the remains of a transmission lock that was removed or broke. There is an assembly inside the transmission housing that runs on the underside of the shift lever rods. This corresponds to cutouts in the shift lever rods themselves allowing them to be locked in position. 

[31nash880]

Lahti35,

You are a wealth of information, thank you.

Happy New Year. 

Have followed your thread. Very nice work. Not up to that much of a resto yet. Try to do a bit each winter then be able to at least do local car shows for summer.

90 years of goo collecting under car is fun to remove. But as you see I am learning something every day.

Thanks...Mark

[31nash880]

What is the purpose of an external transmission lock?

[Lahti35]

The lock itself locks the transmission in neutral so even if someone could get it started they couldn't drive it away. Think of it as an early anti-theft device. 

 

The cable/conduit your missing must have gone to the dash where a key/button/lever would have actuated it. The earlier transmission locks just stuck up through the floor and you had to reach down with a separate key to unlock it. 

 

I'm guessing Nash introduced this type of lock as a convenience over the old style to clear up space for your legs. 

[31nash880]

Thanks for info.

Always learning.

[Lahti35]

17 hours ago, 31nash880 said:

Thanks for info.

Always learning.

No problem, I'm always learning too!

[chistech]

Do NOT leave any grease fitting in the housing or drive shaft. There was never a fitting originally, there was a slotted screw plug that when tightened in, would sit almost flush. The grease fittings were only supposed to be installed to put the grease in, then they were supposed to be removed. Lazy mechanics and car owners left the grease fittings in place which is wrong. The 32 olds manual explains the greasing procedure. Leaving a grease fitting in place on a spinning driveshaft is not only a balance nightmare, but a loose fitting can become a projectile when it comes free. The big fitting Lathi shows is even worse and will really throw off the balance. I’ll look for pictures of the slotted plug.  I balanced my 32 olds shaft (which someone had left a modern 45d zerk fitting in) with the OEM slotted plugs. I told my driveshaft shop guy about the grease fitting being in the shaft and he just laughed telling me he usd to see that all the time on the old shafts but nobody realized years ago that the vibrations they felt were that abnormal or that a grease fitting could be causing them. Remember, most these early cars are geared low, 4:10-4:77 and when you’re topped out in rpm, you might not be going real fast but that driveshaft is turning like a son of a gun!

Edited January 7, 2023 by chistech (see edit history)

[Lahti35]

1 hour ago, chistech said:

Do NOT leave any grease fitting in the housing or drive shaft. There was never a fitting originally, there was a slotted screw plug that when tightened in, would sit almost flush. The grease fittings were only supposed to be installed to put the grease in, then they were supposed to be removed. Lazy mechanics and car owners left the grease fittings in place which is wrong. The 32 olds manual explains the greasing procedure. Leaving a grease fitting in place on a spinning driveshaft is not only a balance nightmare, but a loose fitting can become a projectile when it comes free. The big fitting Lathi shows is even worse and will really throw off the balance. I’ll look for pictures of the slotted plug.  I balanced my 32 olds shaft (which someone had left a modern 45d zerk fitting in) with the OEM slotted plugs. I told my driveshaft shop guy about the grease fitting being in the shaft and he just laughed telling me he usd to see that all the time on the old shafts but nobody realized years ago that the vibrations they felt were that abnormal or that a grease fitting could be causing them. Remember, most these early cars are geared low, 4:10-4:77 and when you’re topped out in rpm, you might not be going real fast but that driveshaft is turning like a son of a gun!

Interesting... I'll look in my manual and see what Nash says for greasing these oldies. Is the plug something like this?

 

I think the Alemite pin type zerks come in 1/8 and 1/4 pipe thread (not sure if they are coarse or fine thread)... you've got me curious!

 

 

[31nash880]

Thanks for the heads up. Found the grease fitting your talking about yesterday. Yes it has a zero fitting in it. Will fine a plug.

Also,maybe under my restoration thread, I mentioned a loose arm on the right side of transmission. Found it to be a clutch stop that was swinging loose. Any particular way this should be tightened?

[chistech]

9 hours ago, Lahti35 said:

Interesting... I'll look in my manual and see what Nash says for greasing these oldies. Is the plug something like this?

 

I think the Alemite pin type zerks come in 1/8 and 1/4 pipe thread (not sure if they are coarse or fine thread)... you've got me curious!

 

 

Yes in 1/8” pipe. Because they’re so thin, they’re PITA to get started especially because they’re slotted and I suppose that also helped contribute to the grease fittings being left in. They’re easy to drop and lose on the floor too. I have a couple are olds driveshafts that I’ll look for and take a picture.

Edited January 7, 2023 by chistech (see edit history)

[Lahti35]

12 hours ago, chistech said:

Yes in 1/8” pipe. Because they’re so thin, they’re PITA to get started especially because they’re slotted and I suppose that also helped contribute to the grease fittings being left in. They’re easy to drop and lose on the floor too. I have a couple are olds driveshafts that I’ll look for and take a picture.

I was unable to locate any info in my Nash books about plugs, it appears that for mid 20's Nash drive shaft alemite fittings were installed at the factory and were intended to be left in place, they even recommend using a grease fitting cover! Maybe Nash accounted for the weight when balancing, or maybe they never balanced them, or maybe they took some time to catch up with more advanced designs. The '31 Nash may be a different story.

 

It does make me curious! ...Be a neat experiment for me to run this summer with the fitting vs. plugs... 

[Lahti35]

14 hours ago, 31nash880 said:

Also,maybe under my restoration thread, I mentioned a loose arm on the right side of transmission. Found it to be a clutch stop that was swinging loose. Any particular way this should be tightened?

Mine has a set screw you tighten to lock it in place. Your throwout carrier is different than mine with the actuating arms being captive on yours. I'd bet your clutch stop is only responsible for setting the clearance between the throwout bearing and clutch.

 

If you haven't found them yet the Nash Club Club of America has a good library and they are able to send you copies of original manuals for most models at a small fee. The club library has been an invaluable resource for my work. http://www.nashcarclub.org/ 

[chistech]

29 minutes ago, Lahti35 said:

I was unable to locate any info in my Nash books about plugs, it appears that for mid 20's Nash drive shaft alemite fittings were installed at the factory and were intended to be left in place, they even recommend using a grease fitting cover! Maybe Nash accounted for the weight when balancing, or maybe they never balanced them, or maybe they took some time to catch up with more advanced designs. The '31 Nash may be a different story.

 

It does make me curious! ...Be a neat experiment for me to run this summer with the fitting vs. plugs... 

that’s pretty crazy but I suppose there wasn’t many smooth roads in the twenties where you’d even notice driveshaft vibration. Those amelite fittings are heavy alone never mind adding more weight with the cover even though it’s minuscule.

[Lahti35]

1 hour ago, chistech said:

that’s pretty crazy but I suppose there wasn’t many smooth roads in the twenties where you’d even notice driveshaft vibration. Those amelite fittings are heavy alone never mind adding more weight with the cover even though it’s minuscule.

I know right, I might as well wrap some fuzzy dice around the fittings too since we're adding caps!