B7800 front wheel shimmy

[Muleskinner]

I have a new B7800 with 13 hours on it and a question. While traveling on a dirt bumpy road, I notice the front wheels rock back and forth like the steering gear is worn out. I tried to move the wheels left and right by hand with the tractor sitting still, but they are tight. Why is there so much play in the steering box on tractors? /forums/images/graemlins/confused.gif

 

[art]

It must have been working the cylinder back and forth and that should take quite a bit. How much were they moving?

 

[Egon]

Is it possible to tighten up the steering wheel box. On my B7100 this can be done.

Egon

 

[ronjhall]

Muleskinner

You didn't give any information on your tractor or in your TBN profile.


I have a B2910 with turf tires and FEL.

When using my MMM there is an area that has ripple in it. The ground was finished with a spring harrow. The tire shimmy over this area when in mid range and max HST pedal. (About 5 MPH). Holding the steering wheel tight helps to control the shimmy. I don't normally grip the steering wheel tight because power steering makes it very easy to steer.

My feeling is this is the tires are trying to follow the contour of the ground not shimmy.

Lowering tire pressure will help to minimize the problem. Check your tire pressure. You may have to much air in the front tires.

Tractors do not have a suspension like a car. All the control is in the tires and front axle rock.

You might check front end toe-in. It should be .00 to .28”.

 

[Muleskinner]

My B7800 is brand new with 13 hours on it. The front wheels move around around five MPH and up on rough dirt road. It just seems like they should stay straight with no side to side play on a new tractor. I have seen older tractors exibit this wobble, but you would think a new tractor's front end components should be tight. The wheels move left and right about one inch.

 

[art]

It could be tire pressure as suggested. The old tractors you refer to had manual steering and the toe-in for the most part other then loose gear boxes was the problem. If yours isn't air pressure or toe-in then it's something hyraulic, I'd first address the other two as they are easier!

 

[narcnh]

Muleskinner, I have a new 7800 with not many more miles on it than on yours. I haven't noticed what I consider to be wheel shimmy, but like Ron said, the tires can shift to follow contours in the surface. The next time I'm on mine, I'll pay more attention to it and give a better description, if I think it might help.

 

[riptides]

No wheel shimmy of any sort on mine.
R4's with 48.6 hours.

I do run it at high speeds to go get washed and waxed of course! /forums/images/graemlins/smirk.gif

Even on asphalt it rides pretty tight.

Ahh, the smell of diesel and the wind in your hair! Ain't life GRAND.
Happy New Year!
-Mike Z. /forums/images/graemlins/smile.gif

 

[Muleskinner]

Hopefully I'm describing the condtion right. The wheels don't cause the tractor to shimmy or shake, they just move around left and right about one inch in either direction going down a dirt road at speed. (High range 2000 RPM) Just seems to me like a new tractor's front wheels should be as tight as a vehicle's and not move around. I have checked the play in the steering compnents. There is none. Tight as can be. I have rocked the steering wheel left and right with no play. It all seems tight. I'm puzzled how the tires can move around like they do when I'm holding the steering wheel in a straight position. Probably a normal tractor steering condition. I'm just not used to it.

 

[narcnh]

Muleskinner, I had my B7800 out today on the farm road and driveway and didn't notice any unusual tire shimmy. I wasn't traveling as fast as you describe, but the tires did shift a little to adjust to irregularities or grooves in the road. It didn't seem wrong to me or a problem in any way. Hope this helps.