Ignoramus18095 wrote:

On 2014-09-04, Pete C. wrote:

Ignoramus16243 wrote:

On 2014-09-03, Tim Wescott wrote:
On Tue, 02 Sep 2014 22:03:18 -0500, Ignoramus16252 wrote:

I have an older Towmotor 30,000 lbs forklift.

It does have power steering where a hydraulic cylinder provides
assistance. It has a power steering gearbox of unknown (to me)
construction.

The problem that it has developed is that power steering works great
when I turn steering wheel to the left, and it does not work when I
attempt to turn it right. Instead, turning right requires an enormous
effort.

What could the problem be here, thanks. Maybe there are some valves in
the power steering gearbox that malfunction?

i

AFAIK, power steering works by having the force transmitted through a set
of valves, that make the thing torque one way or the other depending on
how it's being pushed.

If the valve is clogged, or stuck, it would cause what you see.


I bought an all-hydraulic replacement for this system today. It was at
some point damaged by water and rust and was beyond repair.

Just be careful to check your hydraulic pressures, the hydraulic
steering systems often don't operate at the same pressure as the
hydraulics for the rest of the system, i.e. the mast.

Pete, as far as I understand, the power steering hydraulic system is
completely separate from the hydraulics on the forklift lifting
system.

i

Good, if I recall the last hydraulic steering machine I worked on used
pressure from the charge pump to operate the steering and brakes, about
1/10 the pressure of the main hydraulics.