Excavator solenoid valve TM90501 hydraulic pump proportional solenoid valve TM1022381

Common fault points of solenoid valve

1. Internal wear of the solenoid valve: After long-term use, the wear of the parts of the solenoid valve will lead to poor internal sealing, resulting in air leakage and other problems.

2. Coil damage: The solenoid valve coil is affected by current shock and high temperature during long-term use, which may lead to coil damage.

3. Spring failure: The spring in the solenoid valve may be deformed, elastic weakening or failure during normal use, resulting in the solenoid valve not working properly or not working in place.

4. Leakage: the solenoid valve internal seal or coil damage and other factors may lead to leakage phenomenon, so that the solenoid valve can not work normally.

5. Gas path blockage: The accumulation of dust and debris around the solenoid valve may lead to gas path blockage, making the solenoid valve not work normally.

6. Mechanical failure: mechanical parts damage, error adjustment and other factors may lead to the solenoid valve stuck, motionless and other failures.

7.Coil short circuit or break:

Detection method: First use a multimeter to measure its on-off, resistance value approaches zero or infinity,
That means the coil is short or broken. If the measured resistance is normal (about tens of ohm), it does not mean that the coil must be good (I once measured a solenoid coil resistance of about 50 ohms, but the solenoid valve can not operate, after replacing the coil everything is normal), please perform the following final test: find a small screwdriver, put it near the metal rod through the solenoid coil, and then energize the solenoid valve. If it feels magnetic, then the solenoid valve coil is good, otherwise it is bad.

8.Plug/socket problem:

Fault symptoms:
If the solenoid valve is the kind with a plug/socket, there may be a metal spring problem of the socket (the author has encountered), a wiring problem on the plug (such as connecting the power cord to the ground wire) and other reasons that the power can not be sent to the coil. It's best to get into the habit of screwing the fixing screw after the plug is in the socket and screwing the fixing nut after the spool rod on the coil.