I run a 47 meter and the main won't pick up when fully extended. The mechanic has talked to Schwing and was told to up the pressure this helped a little but I still have drop the 2nd stage and not get all of the reach out of the boom. Any ideas or is this a common problem?

IF IT IS SIMILIAR TO A PUTZ, I MAY BE ABLE TO HELP. I WAS HAVING THE SAME PROBLEM WITH MY 47 METER. MY MAIN BOOM-OUTRIGGER STACK VALVE WAS MAXING OUT ALL THE WAY. I ADJUSTED THE SET SCREW ON THE BACK OF THE LEVER TO WHERE IT WOULD'NT MAX OUT., AND IT FIXED MY PROBLEM. IT WAS ALMOST LIKE WHEN YOU GO TO BOOM UP AND THE BOOM-OUTRIGGER VALVE WOULD GO BACK TO LET THE OIL THROUGH, WHEN IT WOULD MAX OUT IT, IT CLOSED THE VALVE A LITTLE BIT. IT SEEMED IT WOULD GO PAST THE POINT WHERE IT NEEDED TO LET ALL OF THE OIL THROUGH. STRETCH THE BOOM ALL THE WAY OUT AND BOOM UP, WHEN YOU DO THAT LOOK AT YOUR STACK VALVES AND HOLD BACK YOUR BOOM-OUTRIGGER VALVE A LITTLE BIT AND SEE IF THAT HELPS.

Great looking rig.

When's the last time you did a hydraulic service?

On the e-stop block there is a boom relief, as your looking at the block - right side - cartridge style. A 45m-47m pressure is set a the pump 310 bar the redundant relief is set at 330bar, and the main boom valve is set at 350 bar. Does this unit have the Appitech hand valve? 9 times out of 10 this relief cartridge is leaking, take it out of your other unit and install in problem unit. make sure the units are off and hydraulic pressure is zero,There is a test but it is really messy. When the boom is laid out the pump can't over come the leakage.

The E stop on my old schwing had the problem of blowing back or leaking back oil to the tank when under great pressure,such as lifting the main. I bypassed it to test and my boom lifted with ease The E stop is a T that can leak and cause loss of pressure.

First of all thank you to the members of this site you are all very helpful and keep everyone on there toes about being safe.

This is all very helpful advice/tips I will be showing this to the mechanic on monday. I do know that the pressure was raised to 325bar to help, but hasn't done any good yet. I will definately check everything that was advised to look at.

As for the hyd. oil service we got this pump from CPR July '08 I can only assume the oil was new oil, but I will look into that.

I will be posting pics later on the last little job I did last friday.

I'm only asking because after checking the appitech which was working fine ,we changed the filter which solved the problem.

Weave,

I am not disagreeing with you at all. I appreciate the help. I will look into checking the appitech and filters (well have the mechanic look into that, the boss doesn't like for us to do too much on the truck. He pays a full time guy for that)

You know how that is with the slow times, do the job, clean up and get off the clock.

JD, check the boom pressure cut off (pressure any section out except main down, when it is past center it has a 140 bar relief that keeps you from crushing the cradle at the hopper) and it should be at 310 bar.  If it’s not Jeff is going to have to isolate each relief in the boom circuit and set them according to the schematic, but I would set the lowest one at 310 bar.  Make sure that you have a good gauge, and use one that’s limit is the closest to the pressure setting that you require, a 400 bar. (ie don’t use a 600 bar gauge when your setting is at 200 bar).  At 325 bar that thing should come up no problem, I bet you have a gauge that is off.

I will let Jeff read all of this stuff people have mentioned. I am not sure what all he has tried I know he has talked to schwing a lot. Where are you at now Houston?

jimmy reeves

A relief that works over center can you show me or send me a drawing and or explain how this works. I think it would be interesting

Houston for now.  If Jeff has any questions he can call me, send me an email and I'll give you my cell #.  I don't want to post it on the web.