Case 580C Resealing Control Valve
Brought a case 580c couple of months ago and have used it with great success so far. The only part of the hoe that seems to have any power(force) is the bucket. When that starts stalling other functions start operating. There is oil leaking from around the spool ends where the levers attach and have read airmans and the oldmans post on resealing the control valve. I want to test my main relief pressure. I know it is on the loader valve but where do I tee in to test. Roll the bucket back till it stops to dead head and it should read what pressure? I called my case dealer and wanted to reseal the rear control valve and quoted $130 for all the O rings. I read in other post it is closer to $1000 range. So I will need to figure out what when wrong there. So my main questions are. What and where to read the main relief pressure, where are the power beyond O rings they are talking about being missing all the time with these valves. I work for CAT so i have access to a flow meter and gauges. But have not rebuilt a control valve. I feel confident in myself than I can handle the resealing part but should I test replace load checks and other items. I would like others opinions on what they have done to reseal the valve. Thanks
Swing open the battery box, you should see a cap 37* on a fitting, some have been drilled with a 1/8 pipe plug for testing. Pump is 24 gpm at 2000 rpm and 2000 psi, main relief at 2300 psi +/- 50 psi at full throttle. The orings that give the problems are under the reliefs on the backhoe, you will need the right orings and backups, you can replace them all in less than an hour once the sheet metal is off and washed down. Spool seals are not bad to do also once valve is clean.