Pc160lc-7eo hydraulic driven magnet

[Don Smith]

Hi guys. Thanks for allowing me into the group. I have a pc160 2008 yr with 8200 ish hrs. I had a hydraulic driven magnet for ir but upgraded to a bigger on. The new one runs at 26 gallons per minute. The manufacturer suggests that I run it in breaker mode so I don't have high return line pressure, so I don't blow the seal on motor. Problem is that it won't raise the boom fast when loading trucks. We tweaked the mag settings and help the boom but not enough. My old one only did 10 gallons a minute, so 15 in difference and I ran that in power mode. No issues. Does anybody know what the return line pressure is going back to tank?
My deal komatsu dealer would love to come out but I dont feel like giving my money away. Also breaker mode reverse the pedal and its very uncomfortable to run it that way. I don't want to change things, I want everything normal. If I run it in power mode I can adjust the flow thru screen and run my pedal backwards so your foot rests on floor and tie into return side ( which is the pressure side in p mode with pedal back and valve it and go to tank . Just have to change when do with mag and switching to thumb.
Any thoughts.

 

[uffex]

Good day & welcome

I would suggest you only have a set amount of power coming from the machine, if you take more for the magnet it will leave less for the machine operation. This can be less flow (speed) or reduced pressure.I believe you have approximately 75Kw total of power cumming from the machine. If you know what pressure you are using for the magnet, we can see how much power is needed. I was involved in some magnet installations those where activated by a button on the remote control lever (joy stick).
Kind regards
Uffex

 

[92U 3406]

No one can answer what the backpressure is on your particular machine. Too many variables (return hose size, return hose length, number of times the oil flow changes direction, oil viscosity etc). You'll have to put a gauge on the return side at the attachment in order to measure. There should be a backpressure spec listed in the magnet's setup manual. Generally speaking I wouldn't want to see much above 150-175 PSI at full flow.

What spec range for flow is given for the magnet?

 

[Don Smith]

No one can answer what the backpressure is on your particular machine. Too many variables (return hose size, return hose length, number of times the oil flow changes direction, oil viscosity etc). You'll have to put a gauge on the return side at the attachment in order to measure. There should be a backpressure spec listed in the magnet's setup manual. Generally speaking I wouldn't want to see much above 150-175 PSI at full flow.

What spec range for flow is given for the magnet?

Manufacturer wants no more than 300 psi. Never knew this on my old one and ran it for yrs. Manufacturers don't think about operator's comfort when designing things. My lines are 1" down boom and back.

 

[Don Smith]

No one can answer what the backpressure is on your particular machine. Too many variables (return hose size, return hose length, number of times the oil flow changes direction, oil viscosity etc). You'll have to put a gauge on the return side at the attachment in order to measure. There should be a backpressure spec listed in the magnet's setup manual. Generally speaking I wouldn't want to see much above 150-175 PSI at full flow.

What spec range for flow is given for the magnet?

Running at 26 gallons per minute. No more than 300 psi on return

 

[92U 3406]

If you're running 1" straight from the magnet, through a good set of couplers, through a 3 way diverter valve for a thumb and then straight back to tank you should be under 300 PSI on the return from my experience. Again you'd have to actually put a gauge right at the return on the magnet if you wanted the actual pressure.

The manufacturer says a firm 26 GPM or did they give a range? Most of the hydraulic magnets I've setup have quite a range between the minimum and maximum flows, sometimes as much as 35 GPM between the high and low side of the spec.

 

[Don Smith]

If you're running 1" straight from the magnet, through a good set of couplers, through a 3 way diverter valve for a thumb and then straight back to tank you should be under 300 PSI on the return from my experience. Again you'd have to actually put a gauge right at the return on the magnet if you wanted the actual pressure.

The manufacturer says a firm 26 GPM or did they give a range? Most of the hydraulic magnets I've setup have quite a range between the minimum and maximum flows, sometimes as much as 35 GPM between the high and low side of the spec.

We played with settings in computer of machine and have magnet set at 26. There is play up and down, in magnet. I like the idea of a 3 way diverter valve. Could mount behind boom.

 

[Don Smith]

We played with settings in computer of machine and have magnet set at 26. There is play up and down, in magnet. I like the idea of a 3 way diverter valve. Could mount behind boom.

Only using 3/4 from quick coupler to mag and back to quick coupler

 

[funwithfuel]

So for starters, you have 2 pumps @ approximately 41gpm. Keep in mind that is no load free flow. In breaker , one pump dedicated for work, one pump for aux function. Ideally the pumps would satisfy the aux demand and any carryover would help speed up boom flow. You have a 15 gpm difference which isn't terrible until you look at other variables. What is the difference in weight of the attachment?
I don't think you're having an issue with mag flow as you didn't say you were dropping material just that boom up had slowed. The only thing you can do to increase boom speed is to sacrifice flow from option circuit. Before it is asked, raising relief pressure will do nothing since it cannot increase flow.
I would suggest an auxiliary pump driven off the gearcase but that would require quite a bit of fabrication and may overrun your engine to stalling. Komatsu usually matches pumps to engine horsepower pretty tight.

 

[Don Smith]

So for starters, you have 2 pumps @ approximately 41gpm. Keep in mind that is no load free flow. In breaker , one pump dedicated for work, one pump for aux function. Ideally the pumps would satisfy the aux demand and any carryover would help speed up boom flow. You have a 15 gpm difference which isn't terrible until you look at other variables. What is the difference in weight of the attachment?
I don't think you're having an issue with mag flow as you didn't say you were dropping material just that boom up had slowed. The only thing you can do to increase boom speed is to sacrifice flow from option circuit. Before it is asked, raising relief pressure will do nothing since it cannot increase flow.
I would suggest an auxiliary pump driven off the gearcase but that would require quite a bit of fabrication and may overrun your engine to stalling. Komatsu usually matches pumps to engine horsepower pretty tight.

I think removing it from breaker mode makes more sense. If I can put it back on power mode and drain directly back to tank . I not looking to do a bunch of work and money. If I can go power mode and reduce flow to mag and back to tank, then I can change direction on my foot pedal to make it comfortable for my foot

 

[funwithfuel]

Let's go back to how your option is plumbed. Do you have bi-directional flow from your option pedal? The top valve section on your valve bank should run the option. Do you have 1 or 2 solid pipes coming off that valve? Where does the return go? Back to the valve or straight to tank or to a 3 way diverter valve? Pics would help.
Another question, when you're trying to boom up and run the mag, are you hearing the engine load up or is she sounding free. There may be a little left to adjust if she's not loading down.

 

[Don Smith]

Yes bi directional pedal. Lines leave valve block and goes up boom and returns to a block with solenoid. That solenoid switches oil from tank or thru valve to tank. I don't think engine is loading down. Won't be able to get pics till tomorrow

 

[funwithfuel]

Post your serial too. I'll find the PM clinic and adj procedure, maybe there's a little more to squeeze out.

 

[Don Smith]

K45220. Pc160Lceo

 

[uffex]

Good day
Pre emission reg. machines maybe of interest.
Kind regards
Uffex

 

[Don Smith]

Post your serial too. I'll find the PM clinic and adj procedure, maybe there's a little more to squeeze out.

 

[funwithfuel]

Ok. Behind that pedestal, there's a return filter in there. I believe that is in line when returning direct to tank. Check pressure differential across filter. Service if necessary.
I've attached some information that may be helpful.

 

[Don Smith]

It looks like you can return to tank directly thru filter or go back thru valve. Your saying to check pressure thru filter

 

[funwithfuel]

Well only if you're still concerned about return oil back pressure. Make sure your filter isn't plugged up.

 

[Don Smith]

Well only if you're still concerned about return oil back pressure. Make sure your filter isn't plugged up.

Filter is new. Thank you for your insight. I had the book out and can see how to adjust flow thru power mode also. If back pressure isn't a problem then I may switch modes and run my pedal in other direction. If need be I can put a diverter valve at the back of boom to flow oil to tank on other line