Cat 143h transmission

I have one cat 143h s/n1al .when it starts it takes first gear second nothird yes . In ten minutes cant take none gear. Sometimes it take sometimes no. I put reverce and take forward, i put park brake and sometimes one gear is stuck in no go in neutral. What should i look. I put new all coins

Georgios, Is this a problem that has started suddenly or a problem that has been slowly getting worse for some time now..?

I think it would be a good idea to start by doing the basics.

I assume that you do not have a basic Operation & Maintenance Manual. Cat Publication reference for English is SEBU7063. I will look to see if the manual is available in something like German or Italian if that is any better for you. There are no manuals in Greek - sorry.

I suggest: -
1. Drain the transmission oil. Inspect the oil while it is draining for any sign of visible particles.
2. Change the transmission filter. Cut open the old filter and inspect it for particles.
3. Remove, clean, and replace the transmission oil suction screen. Take photos of any particles you find in the screen.
4. Refill the transmission. This will require approximetely 47 litres of SAE30 oil that meets Caterpillar TO-4 specification.

Report back what you find.

This video is for the inspection of an engine oil filter, but the process for inspecting the transmission filter removed from your 143H will be similar.

I do all this but nothing. I change the sensor for vhp and the sensors for the auto trans but . Also the pinion is all new. The machine is taking gears at once and after no. Or is at neutral and with out touch any thing is engage gear at his own

To me it sounds like you have a electrical problem that is intermittent or bad solenoid valve.
Can you try to check it for diagnostic codes?
It would also be helpful to put a pressure gauge on to check the transmission pump pressure and clutch pressures when cold and warm,

Today i open the valves. I found the 5 that is not working. I test it outside with a pinion on and a give 24 v from two batteries and don’t do nothing. Maby this is the problem for all that?

I check all solenoid but nothing. It does the same. It havent the gears forward 2,5,6and reverce 2,5. How can i check if my EMC has the problem?

Georgios, let me try and understand what is happening
you start the machine and you place transmission lever in first position and 1st gear engages
you now place transmission lever in 2nd gear and second gear does not engage
you now place transmission lever in 3rd position and 3rd gear engages
you now place transmission lever in 4th position and 4th gear engages
you now place transmission lever in 5th position and 5th gear does not engage
you now place transmission lever in 6th position and 6th gear does not engage
you place lever in 7th position and 7th gear engages
you place lever in 8th position and 8th gear engaged
you place the lever in 1st reverse and 1st reverse gear engages
you place the lever in 2nd reverse and 2nd reverse does not engage
you place the lever in 3rd reverse and 3 reverse engages
you place the lever in 4th reverse and 4th reverse engages
you place the lever in 5th reverse and 5th reverse does not engage
is this what is happening
do you lose the same gears all the time or do different gears not engage
have you checked the modulating clutch cable is not sticking
also check the clutch pressure switch and wiring on the transmission control valve (disconnect the 2 pin sure seal connector and jump the pins and see if that makes any difference)

Mark250 said:

Georgios, let me try and understand what is happening
you start the machine and you place transmission lever in first position and 1st gear engages
you now place transmission lever in 2nd gear and second gear does not engage
you now place transmission lever in 3rd position and 3rd gear engages
you now place transmission lever in 4th position and 4th gear engages
you now place transmission lever in 5th position and 5th gear does not engage
you now place transmission lever in 6th position and 6th gear does not engage
you place lever in 7th position and 7th gear engages
you place lever in 8th position and 8th gear engaged
you place the lever in 1st reverse and 1st reverse gear engages
you place the lever in 2nd reverse and 2nd reverse does not engage
you place the lever in 3rd reverse and 3 reverse engages
you place the lever in 4th reverse and 4th reverse engages
you place the lever in 5th reverse and 5th reverse does not engage
is this what is happening
do you lose the same gears all the time or do different gears not engage
have you checked the modulating clutch cable is not sticking
also check the clutch pressure switch and wiring on the transmission control valve (disconnect the 2 pin sure seal connector and jump the pins and see if that makes any difference)

Click to expand...

Π

Is engage the f1,3458 and R1,346.all the time the same. If you can help me more what exactly to do. If i keep it about 10 minutes it loses all gears

Georgios, have you checked for service codes if you do not have Cat ET here is the flash code list
the diagnostic plug is near the ECM under the floor on the right hand side

3. Place the Start/Stop Key Switch in the Run position with engine off. When the machine Start/Stop Key Switch is turned to the ON position, the machine will display the Transmission Configuration Code as part of normal operation. For example, when the Start/Stop Key of a 140H is turned to ON, a "41" code will be displayed on the EMS transmission indicator lamp (1). The lamp will flash four times in rapid succession followed with a one second pause followed by one additional flash.

4. To enter the Diagnostic Mode of the transmission ECM, uncouple the diagnostic plug (2). At this point the ECM automatically defaults to the Active Diagnostic Mode. In the Active Diagnostic Mode the ECM will flash out the first Active Fault in memory followed by a three second pause and then repeating the original fault. The original fault will continue to be repeated until the diagnostic plug (2) is reconnected.

5. To enter the Active Diagnostic Scroll Mode, jumper sockets 1 and 2 of the diagnostic receptacle of the diagnostic plug (2). The control will display all diagnostics that are presently active on the system. A three second pause separates the codes as they are displayed. Removing the jumper while the control is displaying a diagnostic code will cause the control to repeatedly display that code. Replacing the jumper resumes scrolling.

6. To enter the Logged Diagnostic Scroll Mode, jumper sockets 1 and 3 of the diagnostic receptacle. The ECM will now display any faults which have occurred which are not presently active. A Diagnostic Code of "12" indicates there are no Logged Faults present. Removing the jumper wire while the control is displaying a Diagnostic Code will cause the control to repeatedly display that code. Replacing the 1 to 3 jumper resumes scrolling.

7. This mode is used to clear Logged Diagnostics from memory. To erase a code, put the control in the Logged Diagnostic Scroll Mode until the desired code is displayed and then remove the jumper. The ECM will continue to display the desired code. Jumper receptacle socket 1 to 4. The transmission indicator lamp (1) will turn off indicating the code has been erased. The lamp will remain off until either the Logged Diagnostic Scroll Mode or the Active Diagnostic Scroll Mode is re-entered. The above process can be repeated until there are no codes stored in memory. An active diagnostic code cannot be erased from memory.

OK from what you have just said you have lost clutch number 4, you need to check solenoid E if this is OK you need to check that the solenoid is getting 24V when in that gear position that uses solenoid E.
to check do not unplug solenoid because it will revert to 5 volts only or less back probe the connecters
if you are getting 24Volts you will need to check pressure for that clutch

Mark where is diagnostic plug 2? Send me aphoto

[QUOTE = "Mark250, post: 920489, member: 50833"] Εντάξει από αυτό που μόλις είπατε ότι έχετε χάσει τον αριθμό συμπλέκτη 4, πρέπει να ελέγξετε την ηλεκτρομαγνητική βαλβίδα E εάν αυτό είναι εντάξει πρέπει να ελέγξετε ότι η ηλεκτρομαγνητική βαλβίδα λαμβάνει 24V όταν σε αυτή τη θέση μετάδοσης που χρησιμοποιεί ηλεκτρομαγνητική βαλβίδα Ε.
για έλεγχο μην αποσυνδέσετε την ηλεκτρομαγνητική βαλβίδα επειδή θα επανέλθει στα 5 βολτ μόνο ή λιγότερο πίσω ανιχνευτή των συνδέσμων
εάν παίρνετε 24Volts θα πρέπει να ελέγξετε την πίεση για αυτόν τον συμπλέκτη
[ATTACH = πλήρες] 225856 [/ ATTACH]

[ATTACH = πλήρες] 225855 [/ ATTACH] [/ QUOTE]
Οι τρεις συμπλέκτες που εμπλέκονται στα 2 f δεν έχουν ηλεκτρικό ρεύμα

sorry I don't understand above post

Mark250 said:

sorry I don't understand above post

Click to expand...

I don’t get any voltage on coin wheni puythis gears. Maby is ECM problem?

if the ECM doesn't sense there is the coil resistance it will NOT give 24v to the circuit
so if there is a break in the wire to the coil you will not be able to check voltage
so check for broken wire between the ECM and the coil
if you need a schematic I will need the full serial number there are 3 different models

Mr mark i put all the trans control and repair it . I put the pins connectors of the E to the F and now I don’t have 1,5f and 1,4 r.can you give me a plan of the wires with the colors to check if is correct connecters in coil? Do you now if this grader have all coils the same?

Need the full Seirial Number to find an Electrical Schematic.
1AL range has two groups of machines and the electrics are different.
Also there are differences in the transmission control valve that depend on Serial Number.