I have searched and not been able to find the answers I am looking for, will be long Please bare with me. Cat 140H. CCA 01223 Started working on this for a customer a while back, had lost some gears. They had already changed a few solenoids on the trans, I finished changing what I remember was the rest. Ended up draining and changing the oil. Pulled filters/screens in the trans. Nothing exceptional to report, wasn’t pretty but not the worst. Swapped a couple parts from a sister 140 to check operation of these items, no change. Time went along and repaired a D5M for them, repaired wiring to fix a problem it had, I read the wiring in the hitch can be a problem, inspected it and looked pretty rough, suggested changing it, we actually changed 3 wire harness. Had lost everything but 1 gear in reverse. After changing we had full reverse gears but no 1,4,5,7 and 8 forward. Replaced harness from shifter to main harness and the wiring harness from main to transmission solenoids, looked a bit rough and cracking wiring. No change, so I read a couple threads and found every gear uses 3 clutches to engage. The common clutch is 1 for these gears, so I need to check pressure for this clutch but not sure what test port to use, looking for a diagram that shows which port goes to which clutch and how to check the pressure, assume hook up gauge and put in gear?? Also what pressure I should have and any other advise on what to check. I have been working Heavy Equipment for 14 years but 98% of my customers run older mechanical equipment so not so knowledgeable on trouble shooting newer electric controlled equipment, do understand it uses like 5 volts to operate solenoids and they need to be checked while installed for accurate voltage but don’t have any new fancy equipment for testing. Can’t afford Cat ET, JD etc, not enough justification for spending all that money with them every year for rights to use. I know its a lot of info but trying to give an accurate run down of what has been done. Thanks
So for clutch #1 You need Test Point "5". You are looking for 329 ± 26 psi on #1 clutch. The specs are slightly different for each clutch. If you want to test all 8 clutches (which might be a good idea) you will need three 5-600 psi glycerine-damped gauges. There was an update to #7 clutch. The pressure you measure will show if that update has been done or not. It's not hard to do, it is only in the control valve. For testing pressures you need the powertrain oil at normal operating temperature, so you'll have to run the machine around a bit to get it really warm before putting the gauges on it. Testing transmission pressures on this machine that does not have a torque converter will require disconnecting and removing the short drive shaft between the transmission output and the differential. That will have to be done after the machine has been warmed up. Attach the Pressure Gauges to test ports (9) and (8). Operate the engine at high idle with the transmission control (lever) in the NEUTRAL position. Record the pressure readings. Attach the Pressure Gauges to test ports (5), (6), and (10). Operate the engine at high idle with the transmission control (lever) in FIRST GEAR FORWARD. Record the pressure readings. Attach the Pressure Gauges to test ports (7), (4), and (10). Operate the engine at high idle with the transmission control (lever) in SECOND GEAR FORWARD. Record the pressure readings. Attach the Pressure Gauges to test ports (3), (6), and (10). Operate the engine at high idle with the transmission control (lever) in FIRST GEAR REVERSE. Record the pressure reading. Come back with your results.
Mr jim just do what nige says. I had pay a lot of money for my 143h at cat and they don’t solve my problems.nige solve all my problems with patience and the grader come in newly condition
THIS IS BEAUTIFUL! Is there a application chart for the clutch engagement for each gear?
Why yes there is...............
Ide be checking electrical and pressure at #1 if I were you.
Be aware that changing a solenoid without changing the valve spool underneath it could mask a problem. The solenoid has to be removed in order to get at the hexagon on the valve body to remove the rest of the valve but when checking issues like the one you are describing I think it's better to swap complete solenoid valves from one station to another rather than simply swapping solenoids. You could have nothing more than a stuck spool. The solenoids operate on 24v. If you are testing for voltage then back-probe the solenoid connection. The solenoid coil resitance should be 8.7 ± 0.4 ohms.
Sir Thank You for the info, when I get a chance to check it I will.
I have to look but I believe the spools were also changed, but need to verify, Once again Thanks.
Jim, another thing...... If you find you have some sort of pressure at the test point for #1 clutch but it’s outside the specifications DO NOT be tempted to try to set it using the adjusting screw on the other end of the valve. There is a specific procedure for setting pressures using shims and spacers that has to be gone through before any twiddling of the adjusting screws becomes necessary.
Sir here is what I got testing today Test port in the order listed above 9- 410 psi 8- 430 5-0 6-420 10- 410 7- 270 4-320 10-400 3- 260 6-420 10-400 Swapped #1 and #2 valves no change 0 psi #1 #2 was good 330 Swapped coils from 1-2 no change I did the screw driver test on #1 coil and it did magnetize when engaged. Thank You
It looks as though it's transmission out time......... If you swapped a complete solenoid valve (rather than just the solenoid) between two clutches and the pressure didn't change then it proves that the solenoid valve is working fine. Either #1 clutch piston seal has failed or the clutch is burned up - which if that happened probably caused the piston seal to fail anyway. Confirmed the #7 clutch has the updated springs/spacers in the control valve. With the former parts the pressure specification was only 223 ± 12psi. With the new parts the spec is 388 ± 20psi. Sorry to be the bearer of more bad news but the pressures on many of your other clutches are out of spec. Here are the results you posted with the specs in brackets. All the pressures indicated in bold are out of spec, a couple of them are off by quite a wide margin. Question: What sort of temperature did you get the transmission oil up to before you tested the pressures.? TP 3) 260 - (333 ± 22) 4) 320 - (285 ± 16) 5) 0 - (329 ± 26) 6) 420 - (387 ± 13) 7) 270 - (341 ± 14) 8) 430 - (405 ± 12) 9) 410 - (387 ± 14) 10) 410 - (388 ± 20) So when the transmission is reassembled the initial pressure will have to be set on each of the 8 clutches. This involves using a blanking plate Part Number 139-7050 sandwiched in between the transmission control valve and the transmission case. The initial pressures are then set by adding or removing 5J-1036 shims (buy a packet of them) behind the springs of the various valve sections. Depending on the clutch station the IP specifications are between 49 and 59psi. The testing/adjustment has to be done with the transmission oil at full normal operating temperature - burned fingers again, sorry..!!. I would suggest that while rebuilding the transnmission you should replace the springs in all egiht stations of the control valve. Make sure that you use the updated parts in #7 clutch station - 1 x 7T-0570 Spring, 1 x 9W-7412 Spring, 1 x 4M-1751 Spacer, & 1 x 5J-1036 Shim.
Here is the procedure to install the 139-7050 Plate. 1. The transmission control valve is fixed in place with 15 identical bolts. 2. Remove the 12 bolts (Ref #6) at the bottom side that are indicated by the blue rectangle. 3. Loosen, BUT DO NOT REMOVE, the top 3 bolts (Ref #4) inside the red rectangle. If these three bolts are removed the complete control valve will be free to fall from the side of the transmission. 4. With the three slots at the top of the plate oriented as shown in the illustration below, slide the plate upwards behind the control valve until the slots engage in the three bolts that were loosened in Step 3. 5. Install the 12 bolts that were removed in Step 2. Tighten all 15 bolts evenly starting from the centre and working to the outside.
Well sir I greatly appreciate the info and help you have provided me, I wont rebuild it. Gonna leave that up to the customer to figure out. Cheers, and Thanks again.
Whoever rebuilds it have them come back and we can work through the rebuild and testing procedure.
Well it looks like we are going to have Cat, rebuild it. Will there be anything I need to do after installing it? Side note-- Where the driveshaft enters the (box) to drive the wheels, what is inside that area, you have to unbolt a circular mount and slide it out of the back. Thanks
Unless the Cat branch that does the rebuild has a transmission test bench they will not be able to set pressures, either initial (see above) or final (what you measured on the machine and gave your results in Post #11 above) pressure. The first thing someone should ask them straight out is “Does the cost of the rebuild include testing and adjustment of both Initial Pressures and Maximum Pressures after the transmission has been reassembled and will a Test Report be supplied showing all the parameter values.?” (That Test Report will not be limited to clutch pressures, it should have a lot of other info on it as well.) Can you post a photo of what you’re looking at.? I think you’re talking about the differential but I want to make sure.
Mr nige why for this h grader is taking pressure at high idle? At mine i take pressure at high idle only when i set initial pressure
It has different transmission control valve George. The test procedure for Maximum Pressure is done at High Idle. It would be nice if the factory had one procedure for all the different types of grader transmission and the only thing that changed was the pressure specifications.
I understand.thanks again
Sir here is a pic of the differential input, is there some kind of clutches or something in here? What is this called to locate it on Cat SIS. Thanks Sorry but had this on the back burner while they decided what to do.
What your photo shows is the control for the differential lock. Group Part Number is 160-7756. The clutch for the differential lock is part of the 8W-5430 differential assembly. If you look in SIS under that group you will find the 154-2688 Differential is broken down in a separate illustration which shows the clutch parts. You should check that the diff lock clutch is not leaking by applying external air to it using a shutoff valve to isolate the internal parts and a pressure gauge to monitor what happens inside.
Got it Thanks again.
Did you find everything in SIS.?
Yes sir, There is a leak in that area that needs to be fixed when the trans is out, the valve to active it, does that use air?
It is a 24v solenoid valve that opens & closes the air supply to the locking clutch for the differential in response to the activation of the diff lock control (electrical) in the cab.
I know I’m late to the party and I don’t know if you tried this . To eliminate an electrical issue you can swap the complete coil with wires connected from one valve spool to the working spool next to it. Yes it will change what gear you are actually in but if the pressure loss changes to the other clutch you know you have an electrical fault. I have seen on 3 of these graders where the ecm is not putting out enough voltage to a coil but does not log a code. You can also air pressure test a clutch by removing the 3 bolt cap from the rear end of the countershaft then remove the cylindrical manifold and blow air into the shaft ports.
Thanks