Hi All My aux hydraulic pump needs replacement. The one on the parts manual part number is 240-2998 but it does not fit. The one on the machine have a part number of A20R378 Made in Japan YP-15 Can someone help me with a part number or info on this pump to order it? My vin nr is: CAT0323DVSDC00803 Thanks
Can you explain in more detail the reason the pump does not fit. Different mounting hole setup, different por sizes, etc.? A photo of the new one might also help.
This is the new one 240-2998
What is the job of the aux pump? My main pump was rebuilt. What will happen if I put this old one back. It seems as if there is play between the gears.
That's a photo from somebody's web site. I was asking for a photo of the new pump you actually bought.
Here they are side by side.
Image from my parts catalog
Do you have a photo of the back side of the main hydraulic pump, where the Aux & pilot pumps are installed.?
Where did you get the new pump from? Your parts supplier could have packaged it incorrectly or just have the wrong part all together.
Closeup of the inside. And the green cardboard is where it should go.
That’s the pilot pump you have off.
That's not the AUX pump in that photo. The AUX pump is an attachment (optional extra) and if the machine is equipped with one it is installed behind that 2-solt cover on the RH side of the photo. The pump on the left is the implement pilot pump. It's shown as part of the 272-6955 main hydraulic pump. Item #5 P/N 126-2016 Pump Gp - Gear (Pilot).
Thanks everyone. Its the pilot, I just ordered it. The info was given to me by the guys who overhauled the main pump. Just hope they did a good job on fixing that. Worst of all are the prices. They quoted me U$ 3,300 for it and would be here 16 December. That's why I bought from another supplier for U$ 850 delivered in 7 days. Just for info; they charged me $5,000 to overhaul the main pump, and it took 2 months. Waiting on parts was the big delay; they said. I ordered the pilot for U$ 360.00. Should be here in 3 working days. and I can return the wrong part too. Thanks again. @Jaxosm on insta.
Hi again. After fitting it all and running it, there is a problem. It's as if the machine want to die if we use hydraulics a lot or quick. Not just one type of movement. Either stick or tracks etc. Should the pump 1 and 2 have the same pressure? It vary a lot. See picture at idle. Video at different actions.
After replacing the pilot pump, you need to calibrate the Power Shift solenoid because this solenoid valve uses the pilot pressure to control the main hydraulic pump. If you are very advanced in excavator settings, this calibration can be done using a monitor and a hydraulic pressure gauge. The minimum pressure and maximum pressure are calibrated according to the pressure gauge.
You need to connect a pressure gauge up to 500 kPa to the Power Shift port. Go to the Service menu, password FFF2, calibration, calibration PS pressure valve. Before this, you need to heat the hydraulics to an operating temperature of about 65 Celsius.
Start calibration, and use the right or left buttons to adjust the lower pressure first, then adjust the high pressure. Look at what pressure will be indicated on your monitor, this should be on the pressure gauge.
Correction for pressure gauge. The gauge is needed more than 500 kPa. Just first look at the monitor what pressure is required for your excavator, and select the appropriate gauge. And before doing the calibration, I recommend checking the Relief Valve (Pilot) pressure. Pressure tap 3. The pressure should be 4100 ± 200 kPa (595 ± 29 psi) Test Procedure Start the engine. Place the machine controls at the following settings: engine speed dial "10" and AEC switch OFF. Refer to Testing and Adjusting, "Engine Performance - Test (Engine Speed)" for engine rpm settings. Increase the hydraulic oil temperature to 55° ± 5°C (131° ± 9°F). Check the pilot relief valve setting at pressure tap (3). The pilot relief valve setting should be 4100 ± 200 kPa (595 ± 29 psi). If the pilot relief valve setting is not within the specification, then adjust the pilot relief valve.
Hi @dmitry_bulldozerman . Thank you very much. I have a mechanic coming Monday with gauges. He had a quick look and also advised adjusting the 2 main pumps pressures. Because the pump was rebuilt, the valves could have been adjusted previously, when the pump was a bit "weaker". Thus pushing out too much "volume". Just to be prepared, do you have their pressures, calibrations, etc?
The pump setup procedure is not very simple, you need Flowmetr. The maximum pressure of both pumps is limited by the Main Relief Valve, its setting is 35000 + 500 - 1000 kPa (5076 + 73 - 145 psi). The performance of the main pump is controlled by the Power Shift valve, which controls the pilot pressure, Power Shift is responsible for preventing the engine from stalling due to pump overload, and the pump performance is also controlled by the cross pressure and NFC pressure. Perform a pilot pressure check and the Power Shift pressure calibration, which I have already written about. First, check if the hoses were mixed up when installing the pump?
Looking at the photo, you need very little to equalize the pressure of the pumps in Stand By. During operation, the pumps operate independently of each other, and they can have different pressures.
Hi all I got the mechanics too look at it. In the end it was a damaged wire for the Power Shift Solenoid. They used their diagnostic computer to find the source. It was working fine since yesterday. Just lost hydraulic power on the tracks and bucket. Boom, swing and stick moves but there is no load on them. The screen display shows the following at idle: Pump 1: 822 Kpa <------ ! ! ! Pump 2: 3253 Kpa Power Shift: 3410 Kpa And an error: 39:581-5 Power Shift Pressure solenoid circuit current is below normal. Could this be another lose/damaged wire? Regards
Screen shows at speed 8. Pump 1: 982 Kpa <<--- ! ! ! Pump 2: 3888 Kpa Power shift: 2438 Kpa
See the attached.
Today the mechanics were here. They tested the wires and switch. The error is gone, but pump 1 pressure is still absent. Pilot pressure is there. Power-shift solenoid is working. They suspect that the pump is damaged or that it does not "slush".
Yesterday the guy who reconditioned the main pump was here. He tried several things and could not get pump-1 to work. He think the "controler"/head could be faulty. He opened it up and cleaned it. Could not see anything wrong. All parts move. Pump have normal case pressure. Pilot pump have pressure. Also I have an error: 39:0374-5 > Rotary brake solenoid valve Could this have anything to do with it? Can I swop the two heads of the pump? Would they fit?
Is there a way to test the head only?
Before ordering an auxiliary pump I would make the supplier prove it against the exact machine serial and the old pump identification, not only the 323D/320D model name. The quote file I would want is the old pump tag or full model code, photos of the mounting flange, shaft or spline, port block, rotation mark, pilot/control connections and any solenoids or regulator parts that may need to be swapped. If the original pump failed internally, I would also check suction screen, case drain/return filter and oil sample for metal before installing the replacement. For the supplier side, ask whether the unit is OEM, aftermarket, reman, used or rebuilt, whether it has been bench tested, what pressure/flow rating was tested, and what voids the warranty. A pump that is close but not exact can still bolt on and then fail because the control setup, rotation or port layout is wrong.