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  #1   IP: 185.2.196.47
Old 04-08-2015, 01:00 PM
tomace27 tomace27 is offline
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Default jcb js70 - metal shards in valve block

Hi
My jcb js70 (rebadged sumitomo) has a hydraulic problem.
When working it last week all the hydraulics failed all of a sudden. The only thing working correctly was the blade. The boom makes an attempt to move but it looks like there is not enough oil/pressure to move it.
At the time I noticed that the right track lever had become very stiff to move.

This led me to think there was a problem with the valve block as the blade is not operated through this.
I removed the valve block and took out the spool valve for the track that seemed to be stiff to move.
I found a piece of metal shard stuck in this. It doesn't seem the have damaged the spool valve though.
I then closely inspected where the hydraulic hoses for the tracks attach to the valve block and found some more shards of metal. About 5 or 6 that would be the size of the head of a match.
Looks looks like they are 2 different colour metals (1 normal steel colour and 1 goldy colour) but both stick to a magnet.
Checked the return filter and its full of metal dust but no big bits really.


Has anyone seen something similar before?
Where could the metal have come from? How do I flush the system and be sure there is no more metal left.

Any help is greatly appreciated.
Thanks
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  #2   IP: 81.153.124.15
Old 04-08-2015, 02:21 PM
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cps140 cps140 is offline
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Default Re: jcb js70 - metal shards in valve block

Hi There, Id say your pump has blew up for want of better words! The golden colour is likely brass from the valve plate or piston bases in the pump! DO NOT run the machine any longer, take the pump of for inspection!
The reason the blade is still working is because it is likely running from a sperate pump (The EX60's are this way)

Were are you based?

Aiden
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  #3   IP: 2.127.125.170
Old 04-08-2015, 10:25 PM
Mick-the-fitter Mick-the-fitter is offline
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Default Re: jcb js70 - metal shards in valve block

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Originally Posted by cps140 View Post
Hi There, Id say your pump has blew up for want of better words! The golden colour is likely brass from the valve plate or piston bases in the pump! DO NOT run the machine any longer, take the pump of for inspection!
The reason the blade is still working is because it is likely running from a sperate pump (The EX60's are this way)

Were are you based?

Aiden
I agree sounds like pump, blade running off separate gear pump, if it's a dual pump, there will be metal in everything that it feeds!

Mick:
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  #4   IP: 185.2.196.15
Old 05-08-2015, 09:12 AM
tomace27 tomace27 is offline
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Default Re: jcb js70 - metal shards in valve block

Thanks guys.

I was afraid it could be the pump. Id does look like there is a smaller pump too that the blade is worked off.

Is it a big job to -
Take out the pump?
Rip up and fix the pump?

Does the whole hydraulic system (pipes etc...) need to be flushed out to get rid of any bits of metal?

cps140 - I'm based in Co. Limerick
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  #5   IP: 2.216.141.158
Old 14-08-2015, 10:23 PM
Mick-the-fitter Mick-the-fitter is offline
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Default Re: jcb js70 - metal shards in valve block

Quote:
Originally Posted by tomace27 View Post
Thanks guys.

I was afraid it could be the pump. Id does look like there is a smaller pump too that the blade is worked off.

Is it a big job to -
Take out the pump?
Rip up and fix the pump?

Does the whole hydraulic system (pipes etc...) need to be flushed out to get rid of any bits of metal?

cps140 - I'm based in Co. Limerick
There should not be any major fragments between the tank and pump supply, empty tank and clean it, clean supply hoses to all pumps, remove pump for repair or replacement.
Making sure the tank and strainer are very clean, then supply hoses to pumps, refit pumps, fill the tank with clean oil, you can install an additional return filter(s) but the metal will never all be removed from the machine unless every motor, ram or valve is stripped and cleaned, and the same with every hose, it's not ideal to run the machine now with all the metal fillings in it, rams will be scored, spools will jam and motors will be damaged.

Mick
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  #6   IP: 86.131.12.45
Old 23-08-2015, 08:35 AM
Zetor Ad Zetor Ad is offline
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Default Re: jcb js70 - metal shards in valve block

Quote:
Originally Posted by Mick-the-fitter View Post
There should not be any major fragments between the tank and pump supply, empty tank and clean it, clean supply hoses to all pumps, remove pump for repair or replacement.
Making sure the tank and strainer are very clean, then supply hoses to pumps, refit pumps, fill the tank with clean oil, you can install an additional return filter(s) but the metal will never all be removed from the machine unless every motor, ram or valve is stripped and cleaned, and the same with every hose, it's not ideal to run the machine now with all the metal fillings in it, rams will be scored, spools will jam and motors will be damaged.

Mick
Hi Mick, does this happen every time a pump fails on a machine? I have a couple of 130's and was intending running them to high hours, I don't mind replacing the pump but the idea of it filling the system with filings sends shivers down my spine.
Thanks ad
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  #7   IP: 90.210.163.31
Old 23-08-2015, 01:37 PM
Mick-the-fitter Mick-the-fitter is offline
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Default Re: jcb js70 - metal shards in valve block

Quote:
Originally Posted by Zetor Ad View Post
Hi Mick, does this happen every time a pump fails on a machine? I have a couple of 130's and was intending running them to high hours, I don't mind replacing the pump but the idea of it filling the system with filings sends shivers down my spine.
Thanks ad
Unfortunately there is not normally a filter system between the pump/s and the spool block, so any problem in the pump will indeed end up down stream from the pump, and if the oil is only going back to the tank it still has to travel through the spool block, in addition to that any service used when the system has been contaminated will be also contaminated.

You may find with the 130's that if you change filters and oil regularly, they will go on for ever, there's no point at which the pumps may decide to implode.

And also no rule of thumb, as to how long things last, out of 100 machine built at the same time with the same hours on them, you may find one will need a pump and another may need a track motor!

Mick
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