Mott Mower Help Needed

Mon May 10, 2004 7:30 am

Strapped on the Mott 4' mower for the first time. It works, but vibrates like mad. Does anyone know the size/part number for bearings that the cutting shaft turns in? I think one or both sides must be bad - I'm afraid it will shake the cub apart. Any other suggestions for eliminating the vibrations? I know I am missing a cutter or two.

When facing slightly uphill, the cub stalls before it can get the mower spinning - should it take this much power to get going or is my belt too tight?

Also, should this mower have an overrunning clutch? I almost got pushed over a rock wall when I put the clutch in - just kept going and going and going.

Help appreciated from experienced users.

Mon May 10, 2004 7:56 am

Scott, been running a Mott for about 16 years. An overrunning clutch would be nice, but I've never found one that will work, With a little practice you get where you can hit the clutch and slip the tractor transmission into neutral at the same time.

Regarding stalling, if it only happens when facing uphill you probably need to adjust the float level in your carb. They do take a little power to get spinning, but not nearly enough power to cause you to stall out if everything els is correct. If the belts are too tight it won't cause it to be harder to turn, but will cause extra wear on the bearings in the idler pulleys and the pto. Note, the belt does loosen a little when you lift it, so be sure to adjust it with the Mott down.

Regarding bearings, there is a parts list on Rudi's manual server page. If you order the original they are fairly expensive (approx. $35), but you can take your old ones to a bearing place to get more reasonable replacements. Replace the missing knives, even though they aren't very big they will through it off balance, and with the shaft spinning at about 2,000 rpm at full throttle it doesn't take much. As big as that shaft is, you wouldn'tthink it would happen, but I've seen several of them that were slightly bent. I suspect a lot of them may have come from the factory that way. Mine used to vibrate, and I would have to replace the right bearing every other year. About 3 years ago I took it to a local machine shop to have him check it. He put it in his big hydralic press and straightened it. The first time I started it, it was so smooth I thought the belt had come off. If you take it to a machine shop, you will need to remove all the knives and take it out of the housing.

Mon May 10, 2004 7:57 am

Scott, I can't help with the bearing numbers but take a good look at the shaft the knives attach to. If that shaft is bent, you will get vibration. Also on the over-running clutch - We quickly learned when I was young that the way to deal with pto driven implements was to depress the clutch, quickly shift into neutral, and then release the clutch so the implement could clear it's load without driving the transmission. It is a learned technique, but can save you some problems.

Mon May 10, 2004 7:01 pm

Like John said, make sure none of the knives are missing, bent, or even badly worn. Any weight out of balance will set up bad vibes. Mine was bad when I first got until a bit the bullet and replaced all the knives, bolts and rings. I was lucky that my shaft was still straight and this fixed the problem.