JCB Beaver Breaker Pack Testing

[Neilom]

Hi all, i have several JCB beaver packs that i am going to maintain for someone, my question is on testing the pressure and flow rate on these machines. I have a webtec flow meter which also has a pressure gauge connected to it. I have connected the flow meter and gauge to the outlet of the powerpack valve block, and then connected the gun hoses to the flow meter outlet and to the return on the powerpack block. I run the machine and move the lever on the beaverpack valve block to engage the pump When i operate the gun i get a reading of 18 LPM on the flow meter and 1300 psi pressure. I would like to know if this is the correct way to test the system and are these readings correct. Any info on testing and adjusting the hydraulics on these machines would be much appreciated

 

[doobin]

They are just a simple gear pump. More revs = more flow. 18lpm isn't terrible, if the gx270 engine then they are rated for a nominal 20lpm.

If the breaker all works fine I really wouldn't worry about anything other than changing the oils and spark plug and maybe cleaning out the fan/oil cooler bit.

 

[Neilom]

They are just a simple gear pump. More revs = more flow. 18lpm isn't terrible, if the gx270 engine then they are rated for a nominal 20lpm.

If the breaker all works fine I really wouldn't worry about anything other than changing the oils and spark plug and maybe cleaning out the fan/oil cooler bit.

Thanks for the reply, the question was mainly for future reference for testing, if i get a problem with the hydraulic side. Engine side is not a problem have dealt alot with these honda engines. I just wanted to make sure i was testing it correctly and the values were good so i know what to look for in the future

 

[charlie2]

Thanks for the reply, the question was mainly for future reference for testing, if i get a problem with the hydraulic side. Engine side is not a problem have dealt alot with these honda engines. I just wanted to make sure i was testing it correctly and the values were good so i know what to look for in the future

do the breakers on these require gassing up like machine breakers do from what i remember if a hydraulic breaker on a machine wasnt working at its best a gas top up generally livened them up again.

 

[V8Druid]

do the breakers on these require gassing up like machine breakers do from what i remember if a hydraulic breaker on a machine wasnt working at its best a gas top up generally livened them up again.

presumably the nitrogen is a gas return spring? My 10' x 1/2" guillo had a nitrogen return system on it and needed recharging every so often ... could always tell as the blade return was sluggish, compared to 'leaping' back up when freshly charged

 

[Rob65]

do the breakers on these require gassing up like machine breakers do from what i remember if a hydraulic breaker on a machine wasnt working at its best a gas top up generally livened them up again.

Why do they use Nitrogen in these breakers as apposed to good old fashioned compressed air?

I appreciate there is circa 20% oxygen in the air. What undesirable effect does the oxygen have?

 

[V8Druid]

Why do they use Nitrogen in these breakers as apposed to good old fashioned compressed air?

I appreciate there is circa 20% oxygen in the air. What undesirable effect does the oxygen have?

from memory, the nitrogen does not mix with the oil

 

[Diggerdavey]

from memory, the nitrogen does not mix with the oil

I think the nitrogen molecules finder it harder to permeate the rubber diaphragm than standard compressed air therefore require less frequent re gassing. I may of course be totally wrong

 

[Rob65]

I asked about the compressed air as I have a pace breaker type gun that I have not used for about 10 yrs so it will most likely need regassing if I want to use it.

I also have a high pressure compressor for filling scuba diving cylinders.

Was just putting 2 and 2 together in case the need arrises.