B7100 squealing at high speed on level ground

petes · Jan 25, 2010

When running along flat ground at high speed (high 3rd gear at more than half throttle in 2wd) on my new-to-me B7100D-T there is an occasional/intermittent squealing that sounds like it's coming from the front of tunnel between the bellhousing and the gearbox. It sounds like a dry bearing kind of noise. First thought was the throw-out bearing, but it makes no difference if the clutch pedal is all the way out or with light pressure on the pedal. I just replaced the transmission shaft pilot bearing, but that can't be it since the shaft doesn't rotate relative to the crank when the clutch is engaged.

Maybe a failing bearing for the front driveshaft or propeller shaft? Are the bearings in the tunnel lubed by the transmission/hydraulic oil? It seems if it was propeller shaft (clutch to transmission) bearings it'd make noise in neutral.

Any thoughts, advice or past experience?

Pacific Pete · Jan 26, 2010

I have the same tractor,as yours. Between the Bell housing and the transmision, there is a bearing with a grease nipple on it. It IS VERY HARD TO SEE. On Mine there is a small hole on the left side of the tractor{ the tunnel that runs from the bellhousing to the tranny}, just big enough to get a grease, gun onto.. if you climb under the tractor with a bright light you will see it in the cut away hole. This maybe your problem. I only found this grease nipple by chance, when I was doing other maintenance on the tractor.

Just another reminder. Change the oil in the steering box often. The top seals wear out and if the tractor is left in the rain, water will enter the steering box. This one of mine just cost me 400.00 to repair, as the balls, from the upper bearing dropped into the Rack and pinion. Good luck Pacific Pete and the crew

petes · Jan 27, 2010

Thanks for the reply. With some research I found a couple other posts of similar sounding noise and conditions that were eventually attributed to the front driveshaft cover tube rubbing on the driveshaft, usually after someone disturbed the rubber boot (i.e. tractor splits). The parts manual shows a bushing in the tube, but it's not clear if it's supposed to be positioned at the top or bottom of the tube. The diagram shows everything (rubber boot, seal, bushing, clamps, etc.) all loading from the top.

I'll have a look for the grease nipple hiding in the tunnel. Thanks for the tip!
I recently bought the tractor ($500 with a FEL and a cracked head) - the steering box was full of water (worn bushing), as was the transmission (torn shifter boot). I drained both and refilled with clean oil to prevent freeze-cracking, I'm planning to tear into the steering box this weekend to flush it out and see what needs to be replaced. I'm hoping that since it's still working it's savable.

I've got family with a summer cabin up a Shuswap. Sounds nice!