Common faults and solutions of main clutch of bulldozer parts

Bulldozers are mainly used to dig road cuttings, build embankments, backfill foundation pits, remove obstacles, clear snow, level the site, etc. They can also be used to shovel and stack loose materials over a short distance. Bulldozers that use a very engaged wet multi-plate main clutch are widely used in construction, but they are difficult to repair after a failure. Let's share some common main clutch failures and troubleshooting methods.

1. Main clutch slipping

When the main clutch of a bulldozer slips, the engine speed is normal and no black smoke is emitted, and the working device works normally, but the machine has difficulty climbing and may even be unable to move. Main clutch slipping is the most common fault of bulldozers. The main reasons are: wear of the main and driven plates; welding of the lock pin of the adjustment plate; the main clutch lever is not in place; the thread engagement between the adjustment plate and the flywheel cover end is poor. Clutch slipping is sometimes very difficult to handle.

The general treatment method is to repeatedly rotate the adjustment disk. If the clutch still slips after multiple adjustments, the transmission is often removed first and the main clutch is disassembled blindly. This not only fails to find the fault point, but also easily damages other parts and delays production, resulting in large economic losses. Therefore, a careful analysis based on the above possible reasons is required for effective troubleshooting.

2. The main clutch lever is heavy

The main reasons are that the oil filter is clogged, the oil supply is insufficient, and the booster does not work; the main clutch hydraulic system is short of oil; the booster is damaged or the booster safety valve has problems; the bimetal sleeve in the moving sleeve is burned. When the clutch lever is heavy, you should first check whether the oil level of the hydraulic system meets the requirements; if the oil level is appropriate, you can temporarily remove the oil filter, and then pull the main clutch lever. If you feel that the lever becomes hard, it means that the oil filter is clogged.

At this time, you only need to clean or replace the oil filter. If the oil circuit is normal, but the main clutch lever is heavy, you can first check whether the booster safety valve is stuck or leaking oil. If the booster safety valve is fine, you must check the booster; or check whether the bimetal sleeve in the movable sleeve is burned, and replace it if necessary.

3. Gears make abnormal noises and are difficult to mesh when shifting gears

The main reasons are: the adjustment plate is too tight; the handbrake has poor braking effect. When the adjustment plate is too tight, it is difficult for the main clutch to separate, so the power cannot be cut off, causing the gears to make abnormal noises when shifting gears.

At this time, the adjustment plate should be adjusted counterclockwise to the appropriate position, that is, the main clutch should be adjusted. If the hand brake has a poor braking effect, the main clutch shaft will still rotate due to inertia even though the main clutch is separated (according to the requirements, the main clutch shaft should stop within 3 seconds when the main clutch is separated), so the gears are difficult to mesh and make abnormal noises when shifting. At this time, the small brake belt must be adjusted or replaced.

4. The main clutch cannot be engaged

The main reasons are: the short pin shaft on the connecting plate falls off; the weight of the movable sleeve is installed upside down; the main clutch cover is not covered during the repair process. Check whether the short pin shaft of the movable sleeve falls off and whether the weight of the movable sleeve is installed upside down (if the weight is installed upside down, the movable sleeve cannot enter the adjustment plate). If necessary, remove the movable sleeve, re-rivet the short pin shaft, and install the adjustment plate. If the main clutch lever shaft is not installed in place, the lever shaft should be adjusted in place according to regulations.

Although the fault analysis and treatment of bulldozers are relatively complicated, during use, as long as the equipment is operated, maintained and serviced in strict accordance with the operation, maintenance and service procedures, and problems are dealt with in a timely manner, bulldozer failures can be effectively reduced.