by-pass on hydraulics

[greencrew]

Can a by-pass filter be put on a bobcat hydraulics? We are talking 3,300 psi.

 

[olympic]

Not on that much pressure. You'd have to tap the filter into a low pressure area, say the return line from the control valves to the sump. Or you could rig up some sort of dedicated low-pressure pump for the bypass.

 

[RJCorazza]

There are industrial high pressure filters, but as 'olympic' states, a low pressure return would be much easier. I have installed several bypass / full flow hydraulic filters on my tractor, and have settled on a Donaldson 3u absolute full flow filter on the return line before the cooler.
The previous (kidney loop) filter was a Motorguard TP taking the fluid from a tapped drain bolt, pumped by a sureflow 12v pump and back to the resevoir fill.
I still have an offline parallel Motorguard setup that uses a 120v sureflow pump. I occasionally run it on the 10 gallon tractor sump, my Bobcat walk-behinds, and lawn tractor hydraulic fluid.

 

[RalphPWood]

On a big system at work I installed a spring loaded check valve in the return line to the sump. The spring in the check valve gave me about 2 PSI back pressure. I'm not getting enough pressure drop to suit me on my return filter on the tractor. I am going to install a valve on the return and throttle it until I get about 10 PSI then remove the handle. I see some systems that have an enclosed system but have spin on filters on the low pressure side. I am curious about whether the spin on filter will take a sandwich adapter. I just handle them one at a time. Not familiar with the Bob Cat. I have done the lube oil and fuel. Even those are all a little different.

Ralph

 

[LarryL]

Some bypass filters have a check valve adaptor that bolts on the the filter and the pressure and return lines go through the valve. I'm doing some research on filters and this valve is a standard option on the Kleenoil filter www.kleenoilusa.com which is used for engine oil and hydraulic fluid.