what is wrong? Cylinder or control?

[Scott in ME]

Hi:

I just bought a Bolens/Iseki G154 with a loader. Two double acting hydraulic cylinders move the bucket. When the pistons are fully retracted, the bucket is all the way up. When the control is in the middle position (forgive my lack of correct wording), the bucket will slowly sag down. The previous owner had used the tractor very little and knew little about it, but told me a mechanic ha told him one of the cylinders needed rebuilding. Neither are leaking externally. I'm thinking that if the bucket is empty, just one of the cylinders should be able to hold it up (assuming one is bad). So I'm guessing that either both cylinders need rebuilding, or the control/valve needs some help. I've only had the bucket full of snow, but it seems to sag at the same rate, whether it's empty or full of wet snow. Can anyone throw some knowledge/experience/suggesions at me? Thanks!

 

[Roadworthy]

It is not likely the control and if so it's unlikely it can be properly rebuilt due to exacting tolerances. I would have both cylinders rebuilt. If the O rings inside one are leaking by the other one is probably the same age and showing the same amount of wear and degradation.

 

[4570Man]

What happens when you try to lift the front of the tractor off the ground with the bucket and hold it there? The cylinders are plumbed in parallel so just one leaky one could cause the problem.

 

[RNeumann]

The seller sounds correct. You would be wise to start with the cylinders. You can cap the cylinder’s hoses for one cylinder to try and isolate which one is bad.

 

[wdchyd]

Yup, piston seal on one will do that, rebuild them both.

 

[CobyRupert]

I've heard that one test is to unplug the hydraulic lines (if possible) and see if cylinder leaks down. If it does, then it's the cylinder(s) not the control valve. If it holds, but only leaks when connected, it's the control valve.

 

[4570Man]

I've heard that one test is to unplug the hydraulic lines (if possible) and see if cylinder leaks down. If it does, then it's the cylinder(s) not the control valve. If it holds, but only leaks when connected, it's the control valve.

That test only works for an extending cylinder so this time it will. For a leaking down loader arm it won’t.