hydraulic lift questions

Fri Jun 10, 2011 9:35 am

loboy 154

Problem #1: The 3pt hitch seems to work correctly but the center rock shaft won't let down when using the mower? If i bleed off the oil at the selector valvebody the cylindar retracts? Could it be a blocked hose? Does the rock shaft go down under pressure or is it a gravity type/pressure release?

problem #2: i was working on the carb linkage with the governer disconnected. At one point it reved up pretty high then just shut off. Now it does not want to restart?

Re: hydraulic lift questions

Fri Jun 10, 2011 1:46 pm

From reading other posts it looks like the problem may just be air in system and not enough weight to collapse the piston. The mower is not installed.
I'll try again after I install the mower but first I have to get it started?

Re: hydraulic lift questions

Sat Jun 11, 2011 6:22 am

The center lift cylinder does not have down pressure, and only will go down by gravity. So, without the mower deck or snow blade on it, it may not retract. I'll bet that it works fine with some weight on it.

Re: hydraulic lift questions

Mon Jun 13, 2011 9:22 am

I tried with a 5' pipe for leverage and it still did not move even an eighth inch. Even prying against the frame and rocker shaft and nothing happened. i thought I was going to tip the tractor over. Something is blocking the fluid from leaving the cylinder?

Re: hydraulic lift questions

Mon Jun 13, 2011 9:48 am

vtwarthog wrote:loboy 154

Problem #1: The 3pt hitch seems to work correctly but the center rock shaft won't let down when using the mower? If i bleed off the oil at the selector valvebody the cylindar retracts? Could it be a blocked hose? Does the rock shaft go down under pressure or is it a gravity type/pressure release?



If you have to bleed pressure off at the selector valve then you may want to check that valve. It may be stuck/clogged.

Re: hydraulic lift questions

Mon Jun 13, 2011 2:34 pm

Properly working, the cylinder will not bleed down with the engine off. For the cylinder to relax, the following must be true.

The engine must be running
The hydraulic lift handle must be in a down (or float) position
The hydraulic selector valve (if equipped) must be in the rockshaft position
Down pressure must be applied to the rockshaft (200 lbs of gravity works)

Note: If no hydraulic selector valve is present, then the hydraulic lift will first actuate the cylinder with the lesser load when lifting.

May also want to check for water in the system. Since this is the lowest point in the system it is common for water to gather at the rockshaft cylinder.

Re: hydraulic lift questions

Sat Jun 18, 2011 8:07 am

Thanks outdoors4evr. That was the info I needed. Everything seems to work as designed now. Here are a couple of picts from the completed project.

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Re: hydraulic lift questions

Fri Jan 11, 2013 7:54 pm

Nice setup.... thought we lost you when you sold the Cub.