SINOTRUK HOWO DOUBLE H VALVE WG2203250003

Description

The double H valve WG2203250003 is An important component of the gearbox :

It is mainly used to achieve the up and down gear shifting of the transmission auxiliary box. Here is the detailed introduction:

Transmission DOUBLE H VALVE WG2203250003 Applicable vehicle models:

The heavy-duty vehicle models such as A7, T5G, and T7H are also applicable to the models like King Prince, Haohan, and New Stear.

Function and purpose of the double H valve WG2203250003 :

As the actuating component for the shift air path switching of the gearbox auxiliary box, when the shift lever is in the low gear position, the air path in the air tube is connected, controlling the shift cylinder’s pawl to move downward, and the low gear teeth mesh within the auxiliary box; conversely, the driving teeth directly drive the output shaft to move, thereby achieving the conversion of high and low gear functions.

Working principle of the double H valve WG2203250003 :

When the clutch is depressed, the compressed air from the vehicle’s air reservoir enters the double H valve. If the low gear is selected, the compressed air will pass through the low gear outlet of the double H valve and enter the low gear inlet of the auxiliary box shift cylinder, pushing the piston of the shift cylinder to move to the right, while expelling the residual gas in the cylinder from the high gear pipe through the high gear side exhaust port of the double H valve, thus achieving the gear shift.

Common faults and inspection methods: If the double H valve malfunctions, it will manifest as slow or inability to switch gears in the auxiliary gearbox. The normal operation of the double H valve can be determined by checking the rebound state of the valve contacts, whether the exhaust plug is clogged, and whether there is any leakage. If there is any jamming, clogging, or leakage, the double H valve assembly usually needs to be replaced.

Notes for replacing the double H valve WG2203250003:

Safe operation: Before inspection, disconnect the vehicle gas source (close the valve of the air reservoir) and release the residual pressure in the system to prevent injury from air pressure.

Accessory compatibility: When replacing, make sure the new double H valve model (such as WG2203250003) is consistent with the original vehicle to avoid installation or functional abnormalities due to incompatible models.
Professional maintenance: If lacking maintenance experience, it is recommended to contact a CRH authorized service station or a professional technician for operation to avoid damaging other components due to improper disassembly.

Installation steps for the double H valve WG2203250003:

Prepare tools and materials: Prepare a 6mm internal hexagonal wrench, a 17mm open-end wrench, a 19mm open-end wrench, as well as sealing paper pads, threaded fastening glue (such as Loctite 243), etc.

Pre-installation inspection: Check if the appearance of the double H valve is damaged, and whether all interfaces are clogged or have foreign objects. Ensure that the valve core and other components can move normally.

Apply thread locking adhesive: Apply the thread locking adhesive to the threaded part of the double H valve connection bolt.

Installation of double H valve: Add sealing paper gaskets on the contact surface between the double H valve and the pneumatic locking valve, then install the double H valve to the designated position, and tighten the bolts diagonally with a 6mm internal hexagonal wrench. The tightening torque should be 23 ± 2 Nm.

Connecting the trachea: Use a 17mm wrench to correctly connect the left and right ends of the trachea to the corresponding interfaces of the double H valve, ensuring a secure and tight connection without any looseness.

Test run verification: Start the vehicle, wait until the air pressure reaches above 0.8 Mpa, drive the vehicle, place the gearshift handle up/down control switch in the H/L position respectively, verify whether the range gear conversion of the auxiliary box is normal, and at the same time check if there is any air leakage at each interface of the double H valves.