I have been experincing something very stange, mabye some one can tell me why when i start to pump and move my boom to the right it acts like it wants to move then stops and then it just jerks around but when i shut the pump off it moves smooth as it did when i first got it , its a 2000 schwing 34x also our 39x has started to do the same thing.   HELP

My 41 does the same thing to the right, they havent totally found the problem yet but it is starting to look like a big flucuation in the voltage to the swing to the right one minute it is getting full power whether it be on rabbit or turtle next second it is getting almost no volts to it

What control system is in the pump? CPC or CPC2

 i changed the solanoid and seemed to get better but it now is up to its old tricks again

i dont know witch it is

Joe your control system is the Vector system and will be different. The Vector has shown no problems of this kind but the the circuit leaves the Vector and goes thru the slew limit switches and down to the Pulsar coils, the voltage drop could be coming from one of these sources.  One thing to try as a diagnostic tool only at the shop is to switch sides and if the problems stays on the right it has to be at the valve or beyond. if it moves look at the circuit first and the Vector last.

Does it have a bypass key in it with green lights in the face of the controller

i am just to new at this!! olny got 2 years under my belt and sometimes this whole pumping thing is over my head(at least when i go and try to problem solve) sorry

Rockhard the diagnostic test will work for you as well remember this is for the shop only.

Each of these units should have what is a Appitech valve and they have a Hugh problem with Oil contamination, add the fact that this function turns a motor vs a cylinder and it is the touchiest setting on the boom.

the 34 is not vector but has a bypass key    the 39 is vector and bypass

can i filter that circuit i have had lots problems with this a mounth ago i had to filter the stroke limeter,   both these pumps get new filters every 10,000 yr?

OK that means the 34x has CPC2 if each unit is doing this which I think your saying is poor response to radio input first make sure the boom runs normal with the hand controls. then if it does check them with the cable control if the function stays poor the look at the Pulsar coils.

I know you said you replaced but if the oil is dirty they start acting funny fast. I notice this function is complained about 4 to 1 over the rest of the boom. I mean slewing in either direction.

All the pumps use a common sump on a Schwing, so yes just filter the hyd tank I filter every truck in our fleet at least 8 hrs once per month with a 3 micron absolute element via a filter cart in attempts to avoid problems. We have reduced these problems by a very large margin by doing this. it will work for you as well. 

thank you sir idont know what id do with out u guys time to get r done

Wow that was great. Its so cool to see stuff like this happen. Good job guys.

rockhard, on your 39m the loop oil from the differential cyclenders must be changed also. it does not dump back into the tank like older pumps.

Rock,

The loop oil deal goes something like this, if you have a 2525 pump kit then you need to exchange your loop oil manually - run the drivers diff down into the material cylinder and close the quarter turn, pressure the pump kit out for 45 sec to a minute and this will keep the loop oil clean if done daily it will inject smaller amounts of contaminated oil in the hyd tank vs say monthly

i dont know what kit our 39 has how ever it is an e rock and has 9 in cyl and it pumps like an rabid dog  it can pump two trucks in under 5 mins

Look at the serial tag on the subframe under the turret usually drivers side, but if it has 9 inch barrels its more than likely a 2023 which means it pumps on rod side and loop oil is on the piston side.

 i will have to show my boss what u all said i really dont much about how this works, but when i learn some thing it sticks. like a said before i appreciate all you guys, an occasion laff and an hart felt moment this site has it all!!!

thank you.

jerky controls: have you noticed milky hydraulic oil?  if so

water contamination from diff cylinders packing is getting in your oil. there is an updated seal pack to stop this. had same problem myself. is your pump really dirty allover?