I. Oil tank supply switch leakage: Caused by damaged graphite and asbestos oil seals at the switch.
Solution:
1. Remove the switch, take out the packing, and make two round washers using oil-resistant rubber sheets. The outer diameter of the washers should be 1 mm larger than the switch housing hole, and the inner diameter should be 1.50 mm larger than the handle screw. Place the rubber washers between the steel washers, then slip them onto the handle screw and tighten the pressure cap.
2. Wrap graphite and asbestos rope between the two steel washers and fill the gap. Tighten the pressure cap.
II. Oil tank drain tap leakage: Caused by rust or failure of the steel ball inside the tap.
Solution:
Replace the steel ball (15 mm diameter; a steel ball from an 80 mm inner diameter bearing can be used as a substitute).
III. Oil pipe flare end leakage: Caused by poor sealing between the flare end conical surface and the flare seat.
Solution:
1. Tighten the connector first at the flared end.
2. After grinding the flared joint, apply sealant to the conical surface, then tighten or saw off the flared end, and re-expand it using an expander.
IV. Oil leakage from hollow screw joints:
Causes include: 1. Uneven oil pipe joint end face and washer; 2. Unevenness at the screw holes on the housing.
Solutions: Grind the joint and washer flat. Machine the hexagonal inner surface of the hollow screw flat, then tighten or apply sealant to both sides of the washer.
V. Oil leakage at housing mating surfaces:
Causes include: Oil leakage at the mating surfaces of the oil pan, cylinder head, valve cover, timing gear chamber cover, transmission cover, starter gearbox cover, etc., usually due to loose fasteners or damaged or ineffective gaskets.
Solutions:
1. Regularly ensure tightness.
2. For parts that are not frequently disassembled, such as paper gaskets, apply red glue to both sides of the gasket.
3. For parts that are frequently disassembled, such as valve cover and filter housing mating surfaces, use asbestos gaskets and apply lead oil to the gaskets. When tightening, the bolts in the affected area should be tightened symmetrically in several stages. In addition, ensure that the gaskets are intact, the mating surfaces of the parts are flat and clean, and that there is no misalignment or deformation of the parts.
VI. Oil leakage at control lever shafts:
Causes: 1. Damaged sealing gaskets. 2. Increased clearance between the shaft and the hole.
Solution: Select suitable oil-resistant rubber gaskets according to the shaft diameter, with an inner diameter 1-3 mm smaller than the shaft diameter. Install them on the shaft surface in contact with the hole wall and tighten.
VII. Crankcase oil leakage: Causes: Damaged paper gaskets or loose screws.
Solution: Remove the oil pan, remove the gaskets for inspection. If the gaskets are intact, clean them and apply a layer of red glue; if damaged, replace them with new gaskets. Apply a layer of red glue. Tighten the screws symmetrically and evenly.
VIII. High-pressure oil pipe leakage: The cause is that after long-term use, the conical surface of the high-pressure oil pipe joint has worn, resulting in a poor seal.
Solution: Place a 1-2 mm long plastic tube with a diameter of approximately 5 mm at the mating point between the conical surface and the conical hole of the high-pressure oil pipe, or place a copper washer with an inner diameter slightly larger than the inner diameter of the oil pipe and an appropriate outer diameter, or replace the high-pressure oil pipe with a new one.
IX. Gearbox gear oil leakage:
The causes are:
1. Excessive clearance between the gearbox bearing and the shaft hole;
2. Wear and aging of the oil seal.
Solutions are as follows:
If the clearance between the gearbox shaft hole is too large, it can be repaired using the insert method. If the leakage is caused by wear and aging of the oil seal, the oil seal should be replaced.
X. Oil leakage from the support roller, track roller, and guide roller:
The causes are:
1. Wear and aging of the rubber sealing sleeve;
2. Severe wear of the sealing ring.
Solutions are as follows:
Replace the rubber sealing sleeve promptly. Replace the upper sealing ring. The two rough mating surfaces of the sealing ring must be properly ground, and a layer of graphite grease should be applied to both sides. After installation, water and dirt must not enter for 24 hours.
XI. Oil leakage at the filler and drain ports:
Causes include:
1. Inconsistent threads and pitch at the seals of the diesel tank, gasoline tank, hydraulic oil tank, diesel coarse and fine filters, high-pressure oil pump, oil pan, and gearbox.
2. Lack of sealing rubber on the diesel tank cap.
Solutions: Ensure consistent screw thread pitch at the seals, using fine threads throughout. Install sealing rubber.
