MTFCA Forum

I opened up the muncie auxiliary transmission that is going on my 26 speedster to clean everything out and check the bearings and bushings. When I went to measure the shafts they were .865, which is very odd and just under 22mm (.8661). Today I went to the bearing shop to replace the two main bearings (input and output) and discovered that they are metric as well. So, were some Muncie transmissions metric?

Often it is the bearing size which dictates how things were manufactured, and many bearings were metric.

Allan from down under.

Almost all industrial bearing ate sized in metric. The ball sizes are in fraction of inches.

Art Mirtes

I have worked on a lot of old cars and equipment, but this is the first prewar American thing that I have ever run across with metric dimensions (bearings and shafts). I am replacing some bushings and the idler shaft (the original is worn). I have not been able to find a hardened 22 mm shaft, so I am stepping up to 7/8 (.0089 larger than 22 mm) which is easily available. The nose of the gears are a bit worn but otherwise ok.

Pretty sure I have new idler shafts on the shelf.

Well that’s interesting, I had no idea they were available. I will send you an email.

Hi Morgan,
I have discovered through the advice of one guy running Muncie's that sealed bearings work well & reduce leakage. Also the main shaft bearings
are the same as a model A trans bearings. Also found that the over the counter (hardware store) bronze thrust bushings don't hold up well.
I would defiantly get that shaft from Dan. I have used countershafts out of old 4 speed pickup transmissions. They are too long & have to be cut
off & drilled for the cotter pin & that's not a fun date in a hardened shaft.
Craig.

Thanks Craig. I am going with the open bearings. I know it will leak a bit since the Muncie has no seals, but, it’s the way they were and, you need to get oil past the input bearing to oil the pilot bearing in the input shaft.

Hi Morgan,
Yes if you install sealed bearings you have to install a grease zerk & grease that coupling just like you do the U/joint @ the rear.
Craig.