My first time posting on your site. I have CAT0980HLPF800516. The bucket functions are slow in all positions except lower. ET is showing 850amps max to lower and the other three functions 450 to 500 max. If I switch the lower wire to lift solenoid, lift function is good. I can do this for all functions. Wires are all okay from ECM and I have switched wires on control levers. In conclusion I want to know is my ECM is giving the correct amps to the solenoids for each function? If not i guess I need an ECM.
Gday, any ideas?
Is this a problem that appeared literally overnight or has it been slowly getting worse for a while.? Have you tried any calibrations yet.? 1. Linkage position sensors 2. Lever position sensors 3. Electro-hydraulic control valve solenoids. A bad ECM is a possibility but unlikely. Certainly do not condemn the ECM until you have done all the relevant tests/calibrations.
Started over night. Slow bucket. I have done all calibration. Changed pilot pump and all valves. But I cant seem to get an answer on the correct amps for each bucket function.
That's surprising. The calibrations are supposed to balance out differences in response of individual solenoid valves. I'll see if I can track down any numbers for "typical" current for implement proportional solenoid valves. You mentioned you have ET. Have you downloaded a Product Status Report and if so can you post it up here. Note that it will need to be in Adobe pdf format (not .xml format) in order for folks on here to be able to read it.
Do you not mean milliamps.? 450/500, or 850 amps would need something the diameter of a battery cable to transmit, not an 18 SWG wire.
I worked on a 980H that eventually one morning had a no lift. Took cover off the front control valve under the Dog bone and found that there was way too much rust on the nuts holding the Electro-Hydraulic Control valves. Once all the dirt was blown out of the area and coils pulled back and all cleaned it worked flawlessly after. Simon C
Yes its milliamps.
Im back with my 980H problems. I think the machine is haunted at this stage. So ive fitted a new pilot pump and new pilot valves and solenoids ive calibrated the implement and all is good with the bucket now. But i still have my brake problem. Ive bleed up the brakes and initially the charge valve did its job and built pressure and cut out. However after an hour or so driving the charge light was back on and i had a very heavy steering. I bleed up the system again but charge light wont go out and now my hyd fan isnt turning. I opened a pipe going to the fan and there is also air in that circuit. Ive check all the suction lines and everything looks good. Im now draining the tank to see i can find anything wrong there. Any help would be appreciated. BTW ive fitted and a new brake accumulator valve and rebuild the old one twice.
Have you checked/tested the accumulator function.?
I have replaced both and when my brake pressure was ok i tested them and all was OK. I was tired of pumping the peddle. Tank is now drained and im changing clamps and rubber hose sections on the pilot and fan suction.
When I look in SIS I cant see how the fan and brake pressure are related but for some reason mine are.
Did you charge the replacements with nitrogen as per the service manual.? What does the System Operation for the fan & brake system tell you.?
Yes i charged them as per the manual. ET is giving me a brake fault but nothing for the fan. It even allows into fan calibration.
Did you put air to the hydraulic tank and bleed the pilot pump test pressure port that is on the left side just behind the drivers side cab where all the other test ports are located behind opening door. New pump could be damaged if it did not pick up properly, but the fact that the boom and bucket function seems to indicate that it is making some pressure. As Nige said how much accumulator pressure are you sitting at. Simon C
No I did not. I read about pressurising the tank in another post but I cant find a place on my tank to connect an air line. I have been bleeding at the brake valve not the test point. A CAT tech charged the accumlators for me as I don't have the gauges. I'm filling the tank now and im going to try again.
What’s with the funky looking oil?
Air in the oil.
Some guys modify a spare filler cap with an air inlet on it. Wrap some rags into a baseball size plug and push tight against the filler hole with a blow gun pipe sneeked underneath the rag and you can put air slowly with a variable trigger air blower to push 1-2 psi of oil up towards the pumps while someone else starts it and pulls on boom up lever. Let off on air before removing plug or you may get splashed with oil. Simon C
Update. Rubber hoses clamps and o rings change on brake and steering pump suction. Started and fan now running but still no brake pressure and no steering. The steering will turn in the cab with a little force but the rams don't move at all and no stress on the pump. I have no oil at the port testing area behind the cab when connected to either steering port. I have a steady but low flow from the brake port. Bucket is working fine.
I am probably wrong but you must have pilot pressure of some sort to be able to move the bucket. Maybe a Guru will be able to help with a hydraulic schematic. Simon C
Yes I definitely have pilot pressure and the pump is new.
He’s got SIS so he has access to the schematics.
I have SIS and ET but im no expert on them. Im in a very remote location in West Africa and trying to get this machine sorted myself. On ET only active code i have is E284 LOW BRAKE ACCUMULATOR PRESSURE. But I still have no steering. Ive asked the guy who gassed the accumulator to come back but hes 2 weeks away at best. Maybe I damaged the pilot pump by not bleeding it correctly on start up but my bucket functions are correct. On the front of the machine i changed everything in the block that's fed from the pilot pump except one shuttle valve 251 7509, its held up in customs with another two rebuild kits for the brake accumulator valve and an implement ECU I dont need now.
Try this then. Get into SIS and look for the “System Operation” document relating to the functioning of the brake and hydraulic fan system. Once you can understand how the system is supposed to work it will help you tremendously in diagnosing WHY it’s not working as it is supposed to. Post a photo of your SIS main page and I’ll try to help you navigate to where you need to be.
Thank, ive found the hydraulic diagram and ive seen a few things i need to check. I will keep you posted.
You really need to find the document that describes how the system operates so that you can understand it first. Once you understand how the system is SUPPOSED to work this could give you some valuable clues on what might be going wrong.
You are right and I actually found them. However as you can see from attached image its saying oil goes from pilot to implement and then accumulator valve. But on my machine pilot outlet in teed with one side going to implement and one going to brake accumulator valve. Is it normal to see differences like this?
I see that as basically two ways of saying the same thing. From a hydraulic perspective it doesn't really matter if the tee is right next to the pilot pump or mounted on the implement valve, the end result is the same. I don't see anything there related to the operation of the hydraulic fan. Can you upload a copy of the hydraulic schematic please.?
The fan is working fine now. The bucket actions are good. I have 500 psi at the implement block and 500 psi at the steering pilot valve input but still no steering. I will check the steering pilot valve output Monday. Am I right in saying that my brake and steering issue are not related if my pilot pump is okay?
I will upload the schematic tomorrow, thanks for all your help.
Not knowing what the spec is for the pilot pressure it's hard to say one way or the other. What is the pressure supposed to be.?
Its 500 psi
Hopefully this is okay
In that case what you have on your machine is correct as per specification. A quick look at the schematic shows that the brake and steering systems share no common lines, therefore I would say you are correct. You need to find the test & adjust procedures for the steering system and start to work through those.
Thanks for confirming. Can you see a link with the pilot circuit and the fan that would explain why I lost the fan. I know its okay now but I would not want that to occur down the line and overheat the engine.
I recall that there used to be a fitting somewhere on the fan system that had a built-in screen which, if it got partially plugged, would reduce fan speed. This may have been on a different model but without access to the Parts Manual it's impossible for me to confirm.