# Outdoors > Outdoor Transport >  Excavator Relief adjustment

## Tentman

My little 2.5 tonne post driver digger got a wee bit of love today, a whole new set of track bottom rollers.

However it has another problem that I have no idea how to pursue..... the main boom relief is "leaking" so the main boom loses power and won't hold up a load unless it's getting control input.

So how hard are these to adjust and is there any specialist equipment that is essential??  Or do I have to take it into town to a specialist??

Thoughts??

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## Harryg

picture of the relief valve would help. 
some you can adjust pressure Others are pre set. 
most likely the O ring are needing replaced

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## r87mm

Mechanic job. If that is the problem as it could be a multitude of things. Then it needs to be set to the correct pressure. Just winding it up could and most probably will cause other issues.

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## bunji

@Tentman Yep as Harryg said ,but most importantly if you are not experienced working with it be extremely cautious ,while we were in Arnhem Land, the local Aboriginal Land Councils would have gear in various stages  of disrepair & twice blokes had to be Flying Doctor evacuated after main lining hydraulic fluid while working on leaks & Valves in hard to reach/see places .

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## csmiffy

Without some proper gauges playing with hydraulics is a shit fight. Boom lift cylinder.seals could be a bit dodge although a bypass check could identify that.
Also possibly spool on control valve?
You could get really sneaky and swap the hoses from the crowd cylinder over and see what happens.
Then it would prove the relief is cactus

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## veitnamcam

I dont think it would be a relief valve as those control maxumim pressure from the pump.
When there is no control input there is no (or shouldn't be) pressure being supplyed to the ram.....the only pressure in it is as a result of whatever load it is holding up.

I suspect you need a piston seal kit in the ram or maybe it has a leaky spool valve in the control .

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## veitnamcam

> I dont think it would be a relief valve as those control maxumim pressure from the pump.
> When there is no control input there is no (or shouldn't be) pressure being supplyed to the ram.....the only pressure in it is as a result of whatever load it is holding up.
> 
> I suspect you need a piston seal kit in the ram or maybe it has a leaky spool valve in the control .


The other thing I have seen in my many many many ram repairs is sometimes the ram tube can be streatched aound the piston in a over pressure situation.

This will present as a barely perceptible  even with a straightedge on the tube buldge.....but it will be measureable in the bore.
This type of problem is pretty much impossible to cause threw normal operation of the machine  (provided the relief valve hasn't been titued with)
Almost invariably what causes those type of failures is using too small a machine for the job and then the abuse starts to get the job done.
Ie ramming stuff with the bucket in travel mode.

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## Tentman

Hey thanks guys.  My machine (an IHI 25 NX2) is in good nick (2100 hrs) and I don't think itd been knocked around.  The hydraulics schematic shows a relief on the main boom valve.  However its beyond me so I shall take on board the wisdom of the forum and get a shop to look at it.

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## veitnamcam

> Hey thanks guys.  My machine (an IHI 25 NX2) is in good nick (2100 hrs) and I don't think itd been knocked around.  The hydraulics schematic shows a relief on the main boom valve.  However its beyond me so I shall take on board the wisdom of the forum and get a shop to look at it.


Can you post up the schematic?  
If it has a separate relief  for that ram? It is possible it could be leaking causing the creap.

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