i have kobelco 160 slow track boom and have a bad pump whine in pump #2 I have already had pumps rebuilt. Anyone have any suggestion where I should look next?
What else did you do when you had pumps rebuilt? Why did you have the pumps rebuilt? What all functions are affected, specifically?
You did replace all filters and clean the strainers? That is typical of restricted suction to have severe whine.
Oh dude, you gave him the answer. Lol, yes, that's what we want to know. Otherwise, all that work may be wasted. You can't possibly be "too" clean when repairing hydraulics
repiace filter and clean strainer rebuilt the pump because of whine and all boom function or slow had a little cavaition on the swing side to side checked the big suction hose it look good one track works fine the other one is slow
Ok. Specifically, which functions work and which do not work. Are the faulty functions tied to one side or the other. For example are boom / bucket / right track weaker or stronger than arm/swing left travel? Did you physically wash out the tank.
Another stage where internal lines inspection may be due.
the track that works off of pump one works good when pump two turn on it whines reel bad and the boom/bucket moves slow it seems like every think that needs pump two is slow I cant figure the whine out checked suction hose and filter the pump rebuilder said he seen nothing wrong with pump . sounds like it starving for oil.
FWF I am with you on the tank here.
if a line between pump and valve body is collapsed will is make the pump whine
Between pump and tank, yes. Do you have a pattern change valve? Do you have single pedal straight line travel? Is your right track or left track slow? Trying to help, need info.
no pattern change valve one track is slower thanks
Which one? Right or left?
not sure been a wild since I was on it I will look tomorrow but the one that work off of pump two was slower
So, let's assume for now you're looking at right track being slow. How comfortable are you with switching servo hoses between arm and boom or bucket and swing.
No. It would be under pressure and would generate tremendous heat. But a collapse on the suction to the pump from the tank , that'll cause all kinds of ugly. Have you checked your tank breather? It maintains positive pressure in the tank to minimize starvation. Probably too late to worry bout that, we gotta see if it's a servo problem, or a controller problem, or pump.
Move this thread from track loaders to the excavator forum. Good luck!
What year or exact model is this machine
2003 acera dyamic 160 Kobelco ymo3
O OK when you asked about collapsed hose between pump and valve body is it a main hose or sevro hose coming off the pump regulator
left track is real slow and weak if u put boom down to pick machine up u have to move the left lever a little bit to pick machine swing is real slow and the bucket moves slow the right track moves good
So left stick and travel functions are weak, right stick and travel are strong? To confirm
there two hoses about one inch from pump to valve body thinking maybe the one from pump two going to valve body may be collapsed being nothing on pump two is working right
yea that's right fwf
Ok. Going back a bit. Can you swap servo hoses from boom to arm or bucket to swing at the main control valve? what we're trying to establish is whether you have a servo issue or a pump issue or a controller issue. You may just have poor drain at the pump controller
What would happen if for example you pulled boom up to the end of Boom travel held it there and then tried any function on your left hand stick would your function speed be increased
Which pump was bad before the rebuild and is it the noisy one now? Many of the shops now days think that rebuilding a hydraulic pump involves installing bearings and seals only. They don't know about lapping the piston and barrel assembly to the seal plate nor do they have the measuring tools to check the piston and barrel fit.
pump two is the one whining I when in the pump first and didn't see nothing wrong then I pulled it back out an sent it to a hydraulic shop and let him know what it was doing when he got in to it he called me an said he seen nothing to make it whine he resealed it and I have the same thing now
fwf the only thing that works normal is the right track ,what or u calling servo I don't see it in manual
On the end of each spool, you have spool caps. On the end of the cap you have a small line which should come from your remote control valve. When you stroke the joystick, that sends servo signal to spool. Spool shifts and allows pump oil to go out to do work, at the same time sends signal to the pump to increase displacement. I guess it's time for gauges, are you equipped?
Some folks call it pilot oil , if that helps Any chance you can post a pic of your main control valve?
https://drive.google.com/file/d/0B3CHoxRUD5qALVJwWWN5REh2UXc/view Lifted from excatech
FWF, control valve
Yeah, all those little hoses going to the spool caps are servo or pilot, but we're past that now. Now you say only R travel works properly. That sucks. Something must be bleeding oil back to tank. I think you'll need gauges. A pair with 7k psi should be plenty. You want to see discrepancies between pumps, what functions yield correct pressure. You'll also need to find cycle times for your machine. We have to start at the beginning and work through. Otherwise, you're wasting money on parts and labor for nothing. You stated that you have the factory service manual. That's a big plus. If you wanna tackle this, myself and others will help you along. I will preach safety a lot. I mean no offense, I just don't know your skill and comfort level. I don't want anyone getting hurt following my instructions.