5011 with stiff power steering

[mark_doyle]

hi guys i am new hear,
i recently bought a 5011 zetor that had being laid up for a couple of years with only 2000hrs on clock, everything on tractor works fine apart from power steering, steering is farly stiff to turn left or right, it is the very same to turn even when jacked up as on the ground or even driving, and when tractor is stoped it gets very stiff so its like its half working, the power steering tank has the red atf oil in it which should be ok,and i also checked the stub axels which are free to turn, i also have a 6011 zetor with very nice power steering so i tryed the steering ram from that and it made no differance
could it be the pump itself a bit week or what you think ,any info would be grate thanks.

 

[hala]

First you must exclude any mechanical problem as i.e. jammed and stiff steering spindles. I think the bushings are made of plastic however not sure. I once had a 4718 and there was plastic bushings and it might be the same springy design on 5011. If you have the same problem with the front jacked up it might be your problem.
The second alternative is the oil-flow and pressure and the pump or the valve inside the steering cylinder might be the problem. However with the front jacked up the steering normally goes relatively easy even with the engined stopped.

Hazze

 

[hve]

I would check the pump pressure first,
..........but do not do what i did on my 6745, and screw the relief valve so far in it split the pump housing the first time i reached full lock!
admittedly this was on the Italian Alloy pump and not the much stronger Zetor Cast Iron pump.

The front spindles should valve big Taper roller bearings, but these will bind up if worn from lack of grease.

Also check the steering Damper if fitted, this can become too stiff if the oil is contaminated and blocks the internal valving.

 

[Renze]

Biggest cause of stiff steering is when 10W/30 or 80W/90 oil is used in the powersteering: ISO 22 hydraulic fluid will do, but its very thin: ISO 46 is standard, which is about the same viscosity as 10W/30.

ATF II is what i use in the power steering: Its virtually immune for viscosity change due to temperature change, and its readily available at every gas station in the country. (as opposed to ISO 22 hydraulic fluid which is only available in arctic countries)

 

[askinner]

Biggest cause of stiff steering is when 10W/30 or 80W/90 oil is used in the powersteering: ISO 22 hydraulic fluid will do, but its very thin: ISO 46 is standard, which is about the same viscosity as 10W/30.

+ Having a front end loader fitted! If it does, there is not much option than to live with it! This and the lack of brakes is my only beef with the UR1's! Love them otherwise