Yanmar vio30 Boom & bucket cylinder problem

[krcola]

Hello everyone,i m new here and i see you know very much about hydraulics

I m having problem with my yanmar vio30,the boom and the bucked cylinders slow down when working and after 20 min they barely move also i get weird sound from hydraulic pump when using that commands

Changed hydr. filter and oil
Reparated main hydraulic pump
I meassured psi the boom gives me 1000psi on low throttle and 2000 psi on full.

Every information helps.

 

[Mick-the-fitter]

Are those pressures when boom is dead ended? Where did you take pressures from?

 

[Quattromike]

Is there an issue getting oil out the tank to the pump.
Is the motor labouring when it's moving slowly after 20mins or is it running normal.
How is the pilot pressure to the stick , is there a separate pump for pilot pressure.

 

[krcola]

Are those pressures when boom is dead ended? Where did you take pressures from?

No its while going up,when boom ended its much stronger i Will measure iz tomorrow but i think arround 3000-3500 i take those pressures on the pilot section

Is there an issue getting oil out the tank to the pump.
Is the motor labouring when it's moving slowly after 20mins or is it running normal.
How is the pilot pressure to the stick , is there a separate pump for pilot pressure.

No pump gets oil and I sent it to company that reparated it 2 Times to check it again they say it is funcioning fine
Motor is not labouring it Works normal but i get strange noise at the hyd.pump when using those 2 commands and they are very slow after 20 min,pilot pressure is separate and i measure on it i think iz gives oil and pressure for those commands
Ps.sorry for my bad english

 

[Mick-the-fitter]

Does it straight track? The main pump needs pilot oil to operate

 

[krcola]

Yes it tracks straight,and the main pump is getting oil and operates good
Could problem be in the main control valves

 

[V8Druid]

individual service relief valves opening (possibly prematurely/broken or weak springs? ) and sticking open or issues with the load sensing circuit (if it's load sensed)????

 

[krcola]

Is there a way to throublesoot relief valve

 

[Mick-the-fitter]

Is there a way to throublesoot relief valve

Plum gauges into main pump P1 dead end the service check pressure, to get a second reading, swap the hoses on the pumps, plum gauges into p2 dead end it!

 

[krcola]

Plum gauges into main pump P1 dead end the service check pressure, to get a second reading, swap the hoses on the pumps, plum gauges into p2 dead end it!

Forgot to bring manometer to do so
So i tried to switch the boom cylinder hoses just to test and It works good and there is no noise in the pump when lifting the boom so i think the valve should be the problem
Tomorrow i will take another mesurments on the main pump as you Said so
And thank you very much

 

[Mick-the-fitter]

Right hang on sounds like there is a restriction, after the pump, before the cylinder, switch the hoses back on the cylinder, change them over on the pump(picture of pump)

 

[V8Druid]

Right hang on sounds like there is a restriction, after the pump, before the cylinder, switch the hoses back on the cylinder, change them over on the pump(picture of pump)

piccies above Mick

 

[krcola]

Just to be sure you meant I change these two on the main pump

 

[Mick-the-fitter]

So there is not clear on P1/P2 hoses does it have quick hitch fitted?

 

[krcola]

No

 

[Mick-the-fitter]

I’m going to say yes, by where the hoses come from

 

[krcola]

Nope

 

[Mick-the-fitter]

Are these cable ties put on by you?

 

[krcola]

Are these cable ties put on by you?

No probb previous owner

 

[Mick-the-fitter]

Looking at the hose size this is where P1/P2 are fed into the spool valve assy, so the issue you have may be pre-existing