Caster on a John Deere

Question

Caster on a John Deere

eqkimball (Mechanical)

(OP)

9 Apr 12 10:26

Basic question-
Have a farm tractor with no power steering and a front end bucket.
The self centering torque is much higher with a load in the bucket, almost undriveable.

If I were to reduce the caster angle, would it reduce the self-centering effect?

I have an idea on modifying caster, but not KPI.

Thanks.

MikeHalloran (Mechanical) · Answer 1 · 2012-04-09 13:00:04

So, buy the power steering.

Mike Halloran
Pembroke Pines, FL, USA

patprimmer (Publican) · Answer 2 · 2012-04-09 19:21:01

As high caster angle raises the front as you turn the steering off centre, of course the more the weight you lift, the heavier it gets and the more it self centres as that lowers the load.

Like Mike says, power steering allows you to steer under high load and still have directional stability under low load.

Regards
Pat
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GregLocock (Automotive) · Answer 3 · 2012-04-10 18:44:51

Whether you get any real benefit depends on the detailed geometry. Only two of the tractors on the farm I worked on had PS- on the others we used to pump the tires up.

Cheers

Greg Locock

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patprimmer (Publican) · Answer 4 · 2012-04-10 20:29:53

The only tractor I ever drove had no P/S, but it also only had a very small bucket

Regards
Pat
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cibachrome (Automotive) · Answer 5 · 2012-04-11 23:22:11

Most tractors have 2 options for mounting the front wheels to increase or decrease the scrub radius. If your front wheels are installed so that the front track width is maxed out, reverse them to minimize the front track width. You can sometimes adjust the steer arm length on green tractors to reduce the steering gain (hence steer torque gradient). These are REAL farm tracors, though, not CUTs or SCUTs.

Pressure greatly affects the effort, Scrub and caster largely affect the gradient (buildup).

I've turned the front axle around on a few to change the caster sign in my younger days, too. But it depends on the brand and model). That can change the rolling effort to bizarre values if you want to try it.

You can always adopt the Mercedes tactic: Put a huge steering wheel on it.

fast4door (Mechanical) · Answer 6 · 2012-08-15 15:16:07

RE: Caster on a John Deere

fast4door (Mechanical) 15 Aug 12 15:16

Time to hit the gym.

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Caster on a John Deere