Noisy Transmission gears 1949 Cub

Wed Sep 09, 2009 8:10 pm

I recently rebuilt a 1949 Farmall Cub. I rebuilt the engine but did not do anything to the transmission except change the fluid.
Could someone watch and listen to this youTube video and let me know if it is supposed to make this much noise?

http://www.youtube.com/watch?v=EgYsy881tMQ

Thanks very much.

Re: Noisy Transmission gears 1949 Cub

Wed Sep 09, 2009 8:14 pm

Nice looking tractor. That sounds more like a bearing or something in a final drive to me but you are a lot closer to tell where the sound is coming from. Is the sound near the wheels, or below you?
Todd

Re: Noisy Transmission gears 1949 Cub

Wed Sep 09, 2009 8:19 pm

Nope, not normal and I didn't even have my hearing aids in.

Normal noise is more of a constant whine or growl.

Re: Noisy Transmission gears 1949 Cub

Wed Sep 09, 2009 8:33 pm

Charlie, Double check to make sure your brakes aren't adjusted too tight. They'll make a loud chatter similar to the noise I here in your video.

Welcome to the site.

Rick

Re: Noisy Transmission gears 1949 Cub

Thu Sep 10, 2009 8:06 am

That seems a little more than usual. You can expect some noise since they are straight cut gears, however, I have been successful in quieting down transmissions with bearing replacement and the first/reverse slider gear and bushing. With one of my tractors, I replaced all bearings and gears from an older model cub cadet. Now it too, is quiet. Looks and sounds like you did a great job on the engine. With that ability, you can refurbish the transmission easily. There are a lot of folks here to help, manuals and pictures are available as well. Welcome, and continued success with your '49.

Re: Noisy Transmission gears 1949 Cub

Thu Sep 10, 2009 7:56 pm

Thanks everyone for your input and suggestions. It's hard to tell exactly where the noise is coming from...some of it is definitely coming from the transmission...but some could also be coming from the lower gears as well. Looks like I have some work ahead of me...i'll check out your ideas. I don't have the time right now to invest a lot of effort right now.

Re: Noisy Transmission gears 1949 Cub

Thu Sep 10, 2009 8:06 pm

My tranny growls while in netural but i think i hear the final drive more than my tranny when i drive it. But 1st gear is noisy and 2nd gear is quiet. I think your final drives maybe low on oil or a bearing maybe bad. "maybe" But Rick maybe right but it maybe a brakeless band because it sounds like steel on the castiron drum.

Re: Noisy Transmission gears 1949 Cub

Sat Sep 12, 2009 1:19 pm

You could jack up the rear end enough to get the rear wheels off the ground (wedge the front axles) and spin em one at a time. You should be able to narrow it down that way. I am guessing a bearing in one of the finals or possibly the diff shaft. That noise should have some roughness with it, so if a bearing you should be able to feel it too.

The input shaft bearings on the tanny will be noisy in N with the Cub running.

Re: Noisy Transmission gears 1949 Cub

Wed Sep 16, 2009 8:15 pm

Good idea. I'll jack up the rear end and spin them one at a time and can hopefully narrow down the source.

One thing I didn't mention earlier but I'm wondering now if it may be a possible root cause of the noise. I had the rear of the tractor sand blasted prior to painting. We taped up every known entry point with extra heavy and many layers of duct tape. It will be interesting to see if sand got inside somewhere and is the source of grinding. i don't have a reference point for the condition prior to the rebuild...the tractor was in a barn and not running when I got it.

Re: Noisy Transmission gears 1949 Cub

Wed Sep 16, 2009 10:39 pm

Careful with jacking the rear end, the front pivots so the back will want to have one side on the ground (left?).

I am leery of sandblasting anything but pieces. But it may be something as simple as sand on the brake shoes?? (there is a drain hole under the brakes)

A mechanics stethescope or screwdriver to the ear may be helpful.

Let us know what you find.

Re: Noisy Transmission gears 1949 Cub

Sun Nov 29, 2009 8:23 pm

I was able to work on the cub over the Thanksgiving holiday. I jacked up the rear end and narrowed the noise down to the transmission. When the transmission wasn't turning the rear wheels were very quiet. Anytime the transmission was turning the noise returned. When I opened up the top cover of the transmission and observed the movement...I noticed that one of the shafts had a lot of play. Looks like I'm going to need to re-build the transmission one of these days. Thanks again for you suggestions and help.

Re: Noisy Transmission gears 1949 Cub

Mon Nov 30, 2009 11:35 am

top shaft bearings are bad, and probably the shaft itself - either the rear bearing surface or its bent.
while i had it in pieces, a Cub Cadet original transmission as an organ doner is very helpful for gears, countershaft, ring and pinion.

the Cub Cadet transmissions have a gear reduction in front of the transmission thats 7 to one - engine turns 3600 RPMs would yield a top shaft turning about 515 RPMs. vs. a cub top shaft turning at engine speed - 1800. add to that the typical use of each tractor, the Cub working 12-14 hours daily cultivating, lets say, and the Cub Cadet mowing the lawn for an hour a week, and more probably stored inside. thats why you want one of those transmissions.

Re: Noisy Transmission gears 1949 Cub

Mon Nov 30, 2009 11:47 pm

to clarify the Cub Cadet transmissions further, any gear drive cast iron Cub Cadet transmission will function as a doner. original, 70's 100's 120's, 140's. some of the 70's and 10X's had a wet brake system that used an extended countershaft. that shaft can be shortened, or a suitable grease retainer fashioned as i don't believe it will interfere with the torque tube.

Re: Noisy Transmission gears 1949 Cub

Tue Dec 01, 2009 8:03 pm

If you also get a distinct burning smell while riding, it very well maybe your brakes tightened a bit too much.
Good luck with your cub and welcome!

Re: Noisy Transmission gears 1949 Cub

Tue Dec 01, 2009 8:27 pm

Lucas Gear Oil as a temp fix.