Hello all, Just joined this forum because I bought my very first excavator. I'm sorry to ask so much but I need some major help!!! I didn't realize how bad of shape the wiring is in. Rats destroyed it. It started right up the first couple times but now it won't even turn over I swapped the battery relay because it wasnt sending power to the starter. Now I have power to the starter and nothing. Any ideas? Maybe a starter solenoid? Would anyone know where I could get my hands on a detailed wiring schematic for this machine? I'm trying to rewire the excavator because the rats destroyed it I'll post a couple pictures if I can. Another problem is that the left track won't move with weight on it. Right track works perfect. I thought it was hydraulics because there was a blown hose but I changed it and still the same. Does any voltage control the tracks hydraulic? Maybe the rats chewed up the wire to the left track?
Oh boy. Hope you got a smokin deal on it, looks like you're going to be busy.
I think a Link-Belt 2650 Quantum is the same machine. I don't have the electrical schematics but you travel problem sounds like the swivel seals are gone.
Damn that's not good. Would it only cause one side to not work? Where is the best place to get a seal kit?
Did you know the wiring was fubar when you bought it?
No I didn't check behind the seat. I should have but it's to late now.
7000 miles? LoL
Good day Please see attached hope it helps you Kind regards Uffex
Lol yeah I screwed that one up. Is 7000 hours decent?
Thank you sir I will definitely use this!
For every chewed wire you can physically see there will be another you cant see. Remove every panel you can and inspect every harness. From the amount of rat **** in those pics, they have lived there a lonnnnnng time
Man what a mess, I've been in situations like that when I worked on these machines, rats and mice love the wire coating sense they're made of soybeans. Your track problem could be a swivel seal blown, the best way to check is with a pressure gauge and something to block track movement.
Wow I didn't know that. Makes since though. Would that cause only one track not to work? But I'll start with that thanks man!!
It could very well be the problem. But you need to check pressures by capping the final drive lines at the track drive and see what happens.
Since the circuit reliefs are in the final drive motors you really don't want to cap the lines and try it. The only relief you will see will be the main relief.
But you will know for certain where to start looking for the drive problem, no?
Actually, that won't tell you anything about flow or the drive problem. The pumps will make up more than enough flow to hide a leaking swivel seal and if this unit doesn't have the travel circuit covered by a main relief you will blow something up. The B machines were basic negative control open center systems.
So what do I need to do then to test the swivel motor? Have some good news though. I got almost everything electrical working. Only thing is that the control on the left side console won't unlock. They are always locked so I can't move anything. Would anyone happen to have pictures of the left hand harness or schematics on it?? There are more wires coming from the console itself than there are on the wiring harness.
If you check pressure with track blocked and pressure is low and then cap off lines at motor first and retest. You will find out if problem works s in motor. If pressure is same the cap lines above swivel which will eleminate the swivel, if pressure is at main relief then you know swivel for is the problem if not then you need to look else where. I did have a machine wit a bad pump regulator once that acted just like this.
This is where you could switch lines around before or after the swivel and get some ideas of what problems follow what lines.
Checking the case drain on the motors is the usual first step to troubleshooting a travel problem. Lock up the track, remove the case drain hose and direct the flow into a container and energize the track. Shouldn't be but a few drops of oil from the drain if the motor is good. A bad motor will squirt oil instantly. Leaking swivels usually show up when a track is slow in one direction only or when you see creep in the other track when trying to turn. It may also manifest with high case drain if a seal on ether end is leaking by. The sure way to find it is to cap off the suspected leaker and open the port next to it. When you pressurize the suspected port you will end up with oil out the open port. In most cases it is easier and cheaper to just pull the swivel apart and reseal it. The problem I've seen plenty of times with weak travel has to do with the pumps. The regulators are for the most part just springs working against a reference pressure to control output. Metal fatigues, meaning the springs loose some tension and the pump doesn't put out like it used to. Usually a flow meter would be used to see that but many times you can adjust the weak regulator enough to make up for the drifting travel. But if a pump is weak enough to cause a travel drift problem it would usually also show up in other functions. Cycle times would be a little slow on boom up or arm out. The problem with messing with the regulators is that you have to know what is going on in the regulator and pump or you can screw up the performance in the whole machine.
Brandon I have a old 2700q they are supposed to be the same as the 9020b accept for the motor. if that is true then you have fuse for your safety lock out, and a relay. Also if your lock out button is on it will stay on even with the lockout lever forword.
If you want to bypass the lockout so you can move the machine . Unplug the solenoid in the pic whith the red probe pointing at it . Jump 24 to the red wire and ground the blue that should bypass your safety lock out. That solenoid block is in the door with the hydraulic pump mounted on the front wall.
Awesome thanks man I appreciate it. That look exactly like my 9020b. I'll let you know if it works out. Would you happen to know of there is anyway I could get the factory drawings? Just in the future when I want to fix it for reals.
Thanks for the reply that gives me a lot better understanding. All hydraulics work good except for that left track. It's both directions unfortunately. I can get it to move very slow if I move it just right. But that's just because the other track is doing all the work.
One other thing that should be considered is the drive coupler in the planetary of the final drive. If it's stripped it could cause your problem also.
Well I was able to work on the excavator again today. I pulled the planetary gear out and it looks good. It's got to be hydraulics. A buddy is going to let me use his gauges so I'll see what I can find out.
Thanks for the info man. I was able to get the factory prints on it. It was two things. My wiring was backwards. There 2 wires the same color so I swapped them and it had power. Then I found out the relay behind the seat was also bad. But the control lock button work now and I can move the machine.
Wish I could post this video but the file is too big. It's a video of me getting the left track off the ground. It will move but slow as hell. Won't move with weight on it. I'm getting some hydraulic guages from a friend so hopefully I can have it traced soon.