Hymac 370c

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Joined: Sun Feb 10, 2008 9:49 am
Real name: terry

Hymac 370c

Post #1 by telboy » Sun Feb 10, 2008 2:37 pm

I have an old hymac 370c an have been having problems with ram seals but today I have a new problem.
The right hand slew ram has what looks like a little pressure relief valve on the end of the ram and each time I use the slew for the backactor I get a jet of hyd fluid any ideas

Regards Telboy

Jeremy Rowland
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Re: Hymac 370c

Post #2 by Jeremy Rowland » Sun Feb 10, 2008 10:22 pm

Hi Terry,

Whilst I'm no expert on hydraulics it sounds to me that you either have too much oil in your system or a relief valve that is not functioning correctly. This would explain why you are continually blowing ram seals and the jet of hydraulic oil from your slew ram sounds like there is too much pressure in the system :?:
Just an idea hope it helps.


Nick Drew
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Re: Hymac 370c

Post #3 by Nick Drew » Sun Feb 10, 2008 11:10 pm

Hi Terry,

And a big welcome to CMN :thumbs_up:

I think this is one for our resident mechanical expert tctractors ;)

Nick :mrgreen:
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martyn williams
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Re: Hymac 370c

Post #4 by martyn williams » Mon Feb 11, 2008 7:46 pm

I think you will need to check oil level/grade of oil and correct pressure of your hydraulics,are the relief valves set too high.Or may be just old seals and o rings.On some machines you will have a swivel joint at the end of your hoses.The o rings may be perished or gone hard.
Hope this helps.

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