A fellow bolter is sending me a Muncie 318 3spd transmission in a few days. He notified me that the imput shaft bearings got rusted over the years and needs to be replaced. My question is if I remove the nose and side cover is there a way to replace the bearings or does it have to be completely torn down? Also is the imput shaft bearings available? Jim
1950 chevy shortbed 3100, 216 with a 3 on the tree.
Yes, you can pull just the input shaft to replace that bearing. You might not even need to pull the side cover, but I'd do that just to check and make sure things are in good shape inside. These trannies are pretty simple and not much in the way of special tools needed for a complete teardown and rebuild.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
There's a retainer nut that secures the bearing to the input shaft with a left hand thread which requires a special thin open end wrench to remove it. If you like, I'll loosen the nut and see if I can free up the bearing on the shaft before Don picks up the transmission. I might even have a good used bearing stashed away somewhere. I'm not sure if the SM 318 and the torque tube earlier trans runs the same ball bearing. Here's an Ebay listing for one I believe will fit.
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
If I understand you, the big bearing needs to be changed on the input shaft. Be careful not to pull the shaft out too far because there are internal needle bearings in there that you can't see on the inside of that input shaft.
Here's the parts listing for the input bearing. That should help get the right one.
And yes, you need to make sure the rollers inside the input shaft stay in place, so taking the side cover off would be good insurance to keep from those dropping into the case.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
Jerry I'll call you when I receive from Don. No need to loosen nut. I'm going try doing it my self, gotta learn some day. I'm sure I can count on you for advice once I start. Thanks Jim
1950 chevy shortbed 3100, 216 with a 3 on the tree.
That is a standard 6207N bearing used in both the closed and open driveline 3 speed transmissions. It's certainly not an $80 part. At most about $30 where I get my parts. That bearing is pressed on the shaft and then the left hand slinger/nut is installed. It's going to be difficult trying to remove and reinstall a pressed on bearing without removing the clutch gear. Fred
1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes 1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes 2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans 1947 Willys CJ2A w/F-Head engine
