Outer Limits 4x4 Board

If anyone on outers knows where i can get a flow chart etc and info on pump pressures, flow rates, what levers etc , for 4 wheel full hydro steer, it would be fantastic. i`m sure there are a few hydraulic people on here. even a couple of links to sites with good tech would be great.......Cheers lukey.......

can you be more specific?

i need to know what components i need as well as a way the hoses all joint up from pump to orbital etc....

Prepare for brain meltdown

http://pirate4x4.com/tech/billavista/PR ... ndex1.html
http://pirate4x4.com/tech/billavista/PR ... ndex2.html
http://pirate4x4.com/tech/billavista/PR ... ndex3.html

Holy Crap, brain melted on first link alone

that second link has most of the info you need


i found a few pics to help

with rear steer you can just 't' off from your pump pressure in to orbital and run to lever valve pictured below.





orbital plumbing



This is a schematic of a typical Open Center steering unit (this particular example is a Danfoss unit).

Note the four (4) ports marked L,R,T and P. These are the four hydraulic fluid connection ports that make the unit operate. They are as follows:

P - Pump. The high pressure input from the pump

T - Tank. The low pressure return line to the reservoir (tank)

L - Left. The high pressure output line to the left steering cylinder port i.e. when you turn the steering wheel to the left (counter-clockwise) this port carries fluid under pressure to the steering cylinder(s)

R - Right. The high pressure output line to the right steering cylinder port i.e. when you turn the steering wheel to the right (clockwise) this port carries fluid under pressure to the steering cylinder(s)





and this is the valve ill probably use for rear steer
http://cgi.ebay.com.au/Hydraulic-Contro ... 563b32b52a

or this one if i go hydro winch

http://cgi.ebay.com.au/HYDRAULIC-DIRECT ... 439db75720


PS
i know that the front steering stuff works as im using it now. the rear steer info is how i plan to do it soonish.
hope this helps

You can't just tee off the pressure line to the rear becouse It will bypass through the front if your only using the rear and bypass through rear if you only use the front. It will work if you are using both at the same time but I imagine that would put all the power to the easyer end to streer but I don't know that for sure. I have mine plumed up with the return line coming off the orbital going back to the rear steer valve and then back to the res. It does however make the font harder to steer when you are using the rear as it backs up pressure through the return, but you get used to it and I don't have a problem with it.

Better to (hydraulicly anyway) plumb the rear steer CV, with high pressure carry over (HPCO) facility in before the orbital valve to prevent excessive pressure in the tank port of the orbital when rear steer valve is used. You will have 2 x lines out of the CV, one HP line to the orbital and one LP direct to tank.

Only downfall, is when rear CV is used, oil flow will be directed out the tank port on the CV and not to the orbital, hence no assist on the front wheels (will still be able to steer tho).

can you mount your orbital up side down? how would the traped air go??
i just try my rear steer set up for the first time. but only the rear would work when you moved the front steering hahahahaha, but the front would not even move. any ideas why im running a 5 port orbital
i think i might set it up like rhetts, if not like the post that bartso posted...

Without looking into schematics, would I be right to assume that if you used a closed centre orbital valve you could run a switchable front/rear/both steer arrangement like a Pettibone, Manitou, etc?