I have a Case 9040B that bogs down and kills the engine when the bucket function is activated. Sounds like the pumps are going into full stroke when the bucket is just getting metered. I checked pump2 pressure and the pressure rises up to system pressure when the bucket is getting metered in both direction, no load. I checked negative control pressure, checked out good at 380psi at both pumps. Checked pilot pressure, checked out good at 580psi. System pressure checked out good. The problem is isolated to the bucket circuit only. I checked the pilot pressure on the bucket 2 spool side, checked out at 160psi when metering. Checked pilot pressure to the arm spool side, checked out at 160 psi when metering. Checked out all the control valve lines to make sure they are in there proper place, checked out ok. I swapped the arm 2 line with the bucket 2 line, the problem goes to the arm. Removed the bucket2/ arm2 spool, it looks good. I replaced the check valve and o-rings inside the spool. Installed the spool, still the same problem. The problem sounds like something is getting restricted or the pump is going into full stroke when not needed. The reason I think the pump is going full into stroke is because when the bucket in stalling the engine and I activate another function, the engine recovers and doesnt bog down anymore. Wierd thing is when I disconnect the bucket2 spool line, everything works fine, no more bogging down and stalling the engine. It does slow down the bucket speed though. Anyone ever seen this problem before? Any recommendations? I usually only work on deer machine, not very familiar with the Case machines. Thanks for any help an advance.
Interesting problem. What happens if you stall out the left track? Does the engine bog down? P2 runs the bucket and also the left track. The other functions share flows from p1 and p2. If stalling the track causes the engine to bog then a likely issue is that someone has turned up the pump regulator on p2 only. This is because its the easy regulator to get to, or perhaps the regulator has failed.
I have not tried stalling the tracks out. I figured that if it was a pump problem that the problem would happen when metering the boom or left track circuit too , because from what I understood, the P1 pump primarily runs the a right track, arm and the P2 runs primarily the bucket, boom, left track. Correct? When metering any other function, including the tracks, the machine runs fine. I also was wondering, what is that little solenoid valve, next to the pilot manifold. I think its has a shuttle valve in the circuit that goes to the bucket2/ arm2 spool. Could that cause an issue like im experiencing? Thanks for the help.
Here's a quick and dirty trick before you break out the gauges. Check the inline fuel filter up by the fuel tank and also check the banjo bolts at the fuel settlement bowl there may be some trash in the bolt holes, be sure and not loose the banjo seal gaskets when you remove them. Another thing you can do is put the machine in L mode and see if it bogs down then. If not then check your fuel lift pump on engine.
I know the previous mechanic performed a full service on this machine. I will check the banjo fittings for trash anyway. Im pretty sure it is not an engine issue to to the other functions besides the bucket going over relief and not killing the engine. I already have hooked up gauges to the pumps. The bucket function goes over relief about 4000 psi when metering the bucket with no load. Sounds to be like the pumps are getting stroked when the shouldnt be. I will check it in L mode and also check the ball fuel system banjo fittings for trash. I will update as soon as Im able to work on the machine. The shop is busy and that machine got put in the back burner, thanks.
boom, and arm share flow from p1 and p2 left track is p2 right track and swing is p1 bucket is mostly p2. Best way to isolate a pump issue on any excavator is from the tracks because they don't combine p1 and p2 oil. I believe the solenoid by the pilot manifold is the swing brake Does the shuttle valve line end up going to P2?
I am having the same issue with the same model machine. Everything works fine but the bucket function will bog the engine out. If the "arm in" is called for at the same time it works as it should.
I took the bucket 1 and 2 spools out today and cleaned them, as well as the reliefs. Now the bucket will not function at all and it bogs the motor to stall when bucket function is called. Before it would open or close somewhat but load the engine to stall. If "arm in" is called it will not load the engine, but it wont close the bucket either. Any help would be appreciated. Im not sure if its related, but while all other functions work correctly, they do bog the machine more than they should with no load. I am new to hydraulics so its possible i did something wrong in cleaning the spools?? or.....?
Okay one thing is, and I don't mean to put you down, but you should not have removed the spools. So we need to address this first. Check to see if your are getting pilot oil flow at spool caps and make sure that you got the centering spring in correctly.
Ok, duly noted. How would I check that the centering spring is correct?
The spring attaches just to one end of spool. Another thing make sure you didn’t swap the spools and put them in wrong place. The arn2 and bucket2 spool has a poppet in it to keep pressure up for the next spool.
Yes I reinstalled them in the correct places and orientation.
Let me do some research on this and I'll get back with you.
You were correct, I did accidentally switch the boom and bucket spools. I corrected that and am at least back where I started. The bucket function completed stalls the engine unless “arm in” also called for.
It also works correctly when you “boom up”. If the left track is activated then it bogs but does not kill the engine. Right track does not affect it. Boom down, and stick out, functions do not affect it either.
I tried the same thing and the problem goes to the boom and the arm, but only boom up and arm in. and both functions go back to normal if you move the bucket at the same time.
Did you set pilot pressure at full throttle and not at idle, did that with my linkbelt and pump regulators would not move set them at 580psi at full throttle and fixed my problem. Just a thought
Does anyone know what this is. I’ve been using the machine with a the pilot line for bucket2/arm2 spool blocked off. I’ve run across at least three other case and linkbelt machines with similar issues.
There are a few issues that can cause your problem. You need to make sure that you are getting the correct fuel pressure to injection pump. Check your banjo bolts at fuel settlement bowl and clean screen in bowl.
I went and looked at a 9010b on Friday doing the same thing but with all functions except travel and swing. It was a drilling rig all its life and I think that has something to do with it. It’s something to do with the pump feedback I think. It runs great and strong except certain functions. I sure it’s in the hydraulics and not the engine. Just like the link belt. Like it’s full stroke on the pump when it shouldn’t be.
There is a row of solenoid valves on both machines back by the pump right next to the hyd. tank. Make sure all solenoids are good using an ohm meter. There are pins in each one of those valves and a spool that can stick and won’t allow certain functions to operate correctly.