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980H Slow Bucket Movement

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frankyakro

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Joined
Mar 25, 2026
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21
Location
Ivory Coast
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.
 
Nige

Nige

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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.
 
F

frankyakro

Member
Joined
Mar 25, 2026
Messages
21
Location
Ivory Coast
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.
 
Nige

Nige

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Messages
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Location
G..G..G..Granville.........!! Fetch your cloth.
frankyakro said:
Started over night. Slow bucket. I have done all calibration.
Click to expand...
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.
 
S

Simon C

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Jul 1, 2015
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3,109
Location
Rocky Mountain House , AB., Canada
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Heavy Equipment Mechanic
Nige said:
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.
Click to expand...
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
 
F

frankyakro

Member
Joined
Mar 25, 2026
Messages
21
Location
Ivory Coast
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.
 
F

frankyakro

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Mar 25, 2026
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21
Location
Ivory Coast
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.
 
Nige

Nige

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frankyakro said:
I have replaced both and when my brake pressure was ok i tested them and all was OK.
Click to expand...
Did you charge the replacements with nitrogen as per the service manual.?

frankyakro said:
When I look in SIS I cant see how the fan and brake pressure are related but for some reason mine are.
Click to expand...
What does the System Operation for the fan & brake system tell you.?
 
F

frankyakro

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Mar 25, 2026
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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.
 
S

Simon C

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Location
Rocky Mountain House , AB., Canada
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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
 
F

frankyakro

Member
Joined
Mar 25, 2026
Messages
21
Location
Ivory Coast
Simon C said:
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
Click to expand...
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.
 
S

Simon C

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Joined
Jul 1, 2015
Messages
3,109
Location
Rocky Mountain House , AB., Canada
Occupation
Heavy Equipment Mechanic
frankyakro said:
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.
Click to expand...
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
 
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