'47 Cub noisy transmission

Wed Jul 28, 2004 12:28 pm

Hello All -- I got my first cub, a '47 SN 5233 a few months ago and after quite a few minor repairs, etc. have her running regularly as a mower. Runs great, but since day one has made a terrible noise from the transmission that sounds like a bearing totally shot -- that metallic rattle noise. Noise is in time with input shaft speed, does not change depending on load, going up hill or down. Same out of gear as in gear, PTO out or in.

Pulled the shifter plate soon after getting tractor home and oil was a mess, flushed with fuel oil, refilled with good gear lube. There was nothing obviously wrong, though, no filings or anything like that. Oil remains clear and clean and has probably run 50 hours now.

Surely all this noise isn't normal, or is it? Please advise,


Pete P.

Wed Jul 28, 2004 12:50 pm

Pete:

For the life of me I could never figure out what the guys were talking about when they said Cub rear ends are noisy. Ellie-Mae my 48 is real quiet and I thought that was normal, so it was confusing when reading threads on noise.

Now that I have Granny, my 47, I now understand what they mean by noise :!: :idea: :roll: :lol: I have never heard anything like that before. Probably nothing is wrong with Granny and probably nothing is wrong with yours. Apparently, that is the nature of the beast - square cut gears......

Wed Jul 28, 2004 2:30 pm

My 47 is noisy too, no obvious problems. It bothered me at first, but I think I'm used to it now.

Wed Jul 28, 2004 6:10 pm

Pete, many cubs have whines and some noise in the transmissions, but the noise you describe is not normal. I assume it stops when you step on the clutch and the input shaft stops turning. By your description I suspect one of the bearings that carry the main shft is bad. There is one at the front of the transmission, and one where it leaves the transmission case to go to the pto. Take the transmission cover off and block the clutch down. Then put the pto in gear and turn it by hand to see if you can hear or feel a rough bearing.

Wed Jul 28, 2004 9:17 pm

Hey Pete,

Congrats on the '47. Another possibility is the fingers on the clutch loose/
out of adjustment.

The "metalic rattle" sounds like the clutch. If the governor is functioning
properly the engine RPM [thus the clutch] RPM would remain about the
same. I have one that I have confirmed is the clutch and it sounds
and feels [due to harmonic travel] sounds and feels like it is in the
tranny.

Just food for thought. Let us know what you find.

Thu Jul 29, 2004 9:30 am

Thanks all. I had to free the PTO shaft but after doing so the bearing felt okay and does not heat. No play or end travel on the shaft so I think PTO bearing is okay. Last night she started making a rattle/grind noise even when clutch is released and I could "feel" the noise in the clutch pedal.... so .... I wonder about that input shaft bearing or maybe the throwout.

I really hate splitting tractors but at least the Cub is small. Thanks for all your help. Any cub clutch pointers or are they similar to others? I'm mostly familiar with Ford N series.

Many thanks,


Pete

Thu Jul 29, 2004 10:17 am

Pretty simple, but there are a couple tricks.

Drive wooden wedges between the front axle and the radiator support casting on each side to kep the engine from flopping sideways.

Don't let either half sag wen seperating, the shaft is one piece and runs from the rear of the transmission all the way into the clutch pilot bushing, and is easy to bend.

The original throwout bearing is a graphite block, not a ball bearing. There are some ball bearing type throwouts available, and when they first went on the market everyone really liked them. Recently though, there has been a rash of problems with them due to the type bearings being used to make them. I talked to John at Jp and he says they have corrected the problem they were having. Haven't heard of any solution from Bates Corp though.

If you decide to go with the original type throwout bearing get one from a Case/Ih dealer rather than aftermarket. They come already impregnated with oil and will last longer.