Hello folks, I am new to this forum. I have a 95 CAT 320L with just under 10000 hours. When putting the machine in reverse the on track right hand side moves extremely slow almost sounds like a hissing noise. no fluid leaking all other functions work fine.
Good day If it is in one direction on one side it is probable that you have a issue with the shock valve. Kind regards Uffex
If possible reverse the main hoses at the motor, or at the swivel under the machine, if the problem is then with forward movement instead of reverse (the control for that motor will be reversed in the cab) then it may be a blown out seal in the swivel joint/rotary manifold.
I have also replaced the gaskets in the swival joint it was happening before and continued after replacing all the seals. I appreciate all your help new to big machinery.
A Serial Number would help to locate accurate technical information. Lots of different 320s out there.
Information is helpful. Still try reversing hoses at the motor or the swivel, will possibly point to motor or valve bank issue. Or identify the spool section try swapping the two port relief valve cartridges.
Good day The port reliefs or shock valves for most crawler circuits are located at the motor easy to switch make sure you have unloaded the residual pressure before you attempt the switch the lines will be open to tank. Kind regards Uffex
I usually like to check case drain on the motor before jumping into swapping the main hoses. It's easier to do and since the case drain hose is smaller it is less of a mess.
True that, and I never put a period after anything with machines, but I can't think of a failure in a hydraulic motor that only occurs in one direction. Still as you say, check the easy stuff first!
Thanks for all the replies 9kk00748 is the number off the machine. had a bit of a dump of snow so tomorrow I plan on investigating a bit more. when I am running it in reverse it sounds like when you only move a hydraulic function a little and it is makes a hissing noise. It is like a valve or something is not opening all the way or is jammed. the machine had many leaks before and I have slowly sealed them all up. It does sound like the hissing sound is coming from under the machine.
Does anyone know where the valve would be located on this machine for the right reverse track.
In the valve block right on the back of the travel motor (arrowed). it's Ref #3 on the cutaway illustration and there are two of them. Not sure which valve is for which direction but I suggest that you pull them both out and inspect. Maybe even try swapping them and see if the problem moves from the reverse direction to the forward direction.
Thanks a bunch will do def sounds like something to do with a valve coming from below the cab. Will update soon.
Just a thought, when you pull the valves out have a good look at the condition of the O-Rings marked 1, 2, 10, & 11 on the detail drawing.
Have you checked your pilot pressure to the spool? It could simply be the control valve dumping to tank from the way you described the symptom and sounds. I am just lurking so don't let me get you off track. I just like checking the simple things first. And so often we tend to go straight to the worst case scenario.
Good point! I am too, when having problem with only some functions, first checking the controls instead of function actuator. Unless actuator fault is obvious.
I have not yet. I dont have that tool at this time however it sounds this could be a good investment. The machine is a 95 so I assume seals and different things will slowly need replacing. i have worked with this for a bit however it is just to frustrating at this point. its the only fuction and direction it does this on.
Well it looks like I am battling another problem at the moment I seem to keep loosing my Prime. It started a month ago would loose power a bit had to just let it idle for min would be fine then started happening more. I blew out the lines for the fuel tank, vacumed removed all bolts no screen found. new filter drained tank. bled started idles ok then you use power or work it it dies after about 2 min and it has gotten worse. I re prime it and it runs ok at idle but once I work it for 1 min it starts dying looses prime. I have now checked everything several times. It appears the fourth injector or line attached to the high pressure pump is weeping from what appears to be the top o ring or something. not much would this be the culprit?
Are the filters sucking dry?
not completely no I can just prime it up again bit air comes out of bleed screw. I fire it up and it idles great. I go to move it or work it and it starts dying on all functions. It will idle fine until I use it.
I have not cracked the lines at the injectors yet wasnt sure if it would make difference considering it would run fire up.
If you are not sucking the filter dry and once you prime it will run again. I think that you are sucking air between the injection pump and filter.
So it could possibly be the weeping on the injection pump fitting that is causing this.
Have you looked at the banjo bolt item #18. There's a screen in there.
I am going to head out now and take the connections off again reclean and try again. I will look for that screen. thanks.
No that would be just a leak. There's either a restriction in the line feeding the injection pump or its sucking in air. If your filter before the injection pump ( primary filter) is dry and the other is full then you are sucking in air in that line or restricted. If both filters are dry. Then either you are sucking in air on the lines from the from the tank to lift pump, or sucking air after the lift pump to the water separator. Or restricted. It should flow tank, lift pump, water separator, primary filter, injection pump.
Made some progress tonight I thank everyone again. I am new to heavy equipment and hydraulics. I found the bango bolt under the lift pump as well as a rust covered and crap filter I removed it and will tighten bleed everything tommorow.
I dont see a water separator on the machine I will have to take a closer look.
Seems like a new issue everytime I turn around. I turned the machine off the other day and came back in the morning to start it however nothing. I can hear the solonoid but the starter does not engage. The lights and everthing on the ignition work well just not I turn the key and it is not cranking. I had the complete starter rebuilt last summer.
Machine will probably have a separate starter relay ahead of the solenoid, you may be hearing that. May also have a "Safety relay" which interfaces between the alternator and the starter relay to prevent the operator from engaging the starter when the engine is already running. Or any time it kinda feels like messing with you.
Cat doesn't use a safety relay. The key switch is set up so that you can only hit start position once. If the engine doesn't start then you have to put the switch to the off position and then try to start the engine again from there. There is a switch on the hydraulic lockout on the left side console. Make sure the lever is all the way in the cut off position before trying to start the engine.
Now you made me unlazy myself and look it up to be sure, the 9KK were Catabishi, and while they may have the American key switch, they have Mitsubishi wiring, so actually they do have a safety relay in the circuit breaker and relay box along with the starter relay and the glow plug relay. 094-2080: RELAY SAFETY. Not that I'm sure that's the problem, more than likely it's something more simple like the lockout switch or a stuck solenoid.
ok here is an update I replaced all the batteries and fixed up some connections. The machine still continues to just click except a couple times it was not really an attempt. The loud click is coming from one of the relays behind the fuse box you can feel the juice in the wire and the relay or solonoid making loud noise. Could this be the issue?
The relay or solonoind I feel the this from is the bottom one that has yellow and red wire in it.
Typically the one with the fat Yellow lead would be the glow plug relay, it has a fusible link. Probably need to get someone to post up the CAT schematic for your serial number.....
Refer the attached image for the identification of the components. Normally when we turn start key to on position that shutdown relay will activate once by the controller and that will energize the shutdown solenoid once as well. So if that relay engaging sound happens only once at the start, it is OK. I think you have to check the starting circuit again Including hydraulic activation control switch.
Few months earlier I also came across with some electrical issues with our excavator as well. At that time i draw a little diagram to simplyfy things and that includes starting circuit, shutdown circuit,etc. I think though the picture is not that good it will be useful to you if you follow it carefully.
"Cat 302" check your in box. I have sent you electrical schematics as well.
Start at either end, maybe jumper the starter solenoid hot to see if the starter engages, then work your way back to the starter relay, etc. both ends of the starter relay circuit could have an issue, either the interlock switch or the ground at the safety relay... And of course it all starts at the key switch which feeds the interlock/neutral switch.