I guess I am going to need to get schooled up a bit on working with our new to us excavator. There seems to be several zerks on the machine I assume that can be used to purge or test the system. I am fighting a couple different issues and need to figure out what is going on. I think my pilot system operated under 500psi and the main system is 3600 psi max. Should a guy just go buy some universal gauges or is there a cheap kit out there to get everything that I need? I was hoping there would be zerks on the main valve block for the high pressures but appears there is only zerks on the end blocks to look at the pilot pressures. I would think there would be a more positive clamping zerk fitting rather than the grease gun type of deal but I am new to this..
The brand of machine would help.
Caterpillar. Sorry. I figured most would be the same
There is nothing cheap about high pressure hydraulics in any way. I bought my gauges, hoses and special fittings over time from a Parker hose dealer here locally. I think glycerin filled gauges were $35.00 a piece and I have six of them of different pressure ranges. Cat uses the common quick coupler fittings so I lucked out on those. Just the same they run around $35 to $50 for the female ones and $25 or so for the male ends. I've got 15 or so of the females and ten or so of the male ends. I used super two wire hoses instead of the plastic hose. As I recall there are six of those hoses at $70 or so dollars apiece. They all have #4 JIC female fittings on the ends. After all this I got other adapter fittings, for working on other brands of machine when needed, and there is probably $1,000 in one box. I suppose I have $2,500 in replacement cost for the troubleshooting box. That doesn't count the flow meter that I sold a couple of years ago.
Cat gages are $40-50 each now. Depending on what you are testing you need 50 psi, 140, 500, 3500, 5000 and 8000 gages. Normally you'll need at least 2 of each. The gage is most accurate in the middle of its range. For safety reasons we now use the digital electronic gages with transducers. These are great except for the price and sometime you need to see the needle sweep so out come the mechanical gages.
You mention the JIC #4 but IIRC, that is a threaded flare fitting nearly identical to an AN fitting. The fittings on this machine are just like a zerk with a ball only next size bigger. I assume there is some special fitting for that? Kind of scary not having threads.
I think you may be looking at the bleed fittings.
Pardon my ignorance but I thought the bleeders doubled as test ports. If that is not the case, where is a guy supposed to test from? I assume the center bolt on the pilot blocks on each side of each spool is housing the spool spring. I must be missing something here because I cannot find one single AN style fitting on this machine that looks like a service port.
Machine model and the 3 letter/digits of the Serial Number prefix ..?
51u2335
This machine goes back way beyond the days of quick couplers for test ports, so quit looking - there aren't any. Just a quick look at the Test & Adjust procedure for the hydraulic system indicates that tee-offs for test lines have to be "hard-wired" into the machine befire you can test it, or plugs have to be removed from valve bodies in order to connect a test gauge (or gauges). Not simple. The bleed valves are just that, bleed valves, and are not recommended to be used for testing. Maybe Lee can suggest a more practical way of doing it.
It would seem one of the easiest ways might be to remove the bleeder completely which I think threads into a 1/8" NPT thread, then I can install AN adapters. Or I guess if I felt froggy, I could put service Tsin each of the bleeders so I could have a bleeder and service port there. But that seems a lot of work for no reason just yet. If air gets in, can it be worked out naturally with cylinder cycling or must it be bled? I just though with the double acting cylinders, they might self purge to an extent.
What is the problem you are trying to troubleshoot? Do you just need to check pilot and main?
I have posts in the excavator section regarding the issues. rough swing acceleration and erratic stick function. Really need to start by checking some pilot pressures and go from there. I guess I am hoping this is a pilot issue in which rebuilding the pilot blocks would not be all that bad.