7 Reasons And 5 Solutions of Excavator lost arm

Sometimes you will encounter the situation where the excavator has lost its arm. In the end, will your excavator lose its arm? How to solve the problem of arm failure?

excavator lose its arm

What is the excavator lose arm?

Excavator lose arm is also known as the boom, self-falling, falling pump and so on. Simply speaking, the arm is actually a manifestation of the excavator’s arm weakness. When the boom is lifted, the boom or arm will automatically fall without the control of the lever.

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When the excavator has a broken arm fault, different manifestations will also appear. The fault phenomenon can be roughly divided into a boom arm, a small arm drop arm, a middle arm drop arm, a cold car normal hot car drop arm, and the like.

7 Reasons And 5 Solutions of Excavator lost arm

7 Reasons And 5 Solutions of Excavator lost arm

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Common reasons for 7 points of arm failure:

1. The arm caused by the hydraulic oil failure. If the cold car is in a normal hot car, it is very likely that there is a problem with the hydraulic oil.

2. The hydraulic cylinder of the excavator is faulty, especially if the oil seal of the cylinder is damaged or aged, resulting in leakage of the oil seal.

3. Distributing valve valve hole blockage, spool wear, excessive spool clearance, distribution valve main safety valve wear and damage, caused by the size arm boom.

4. When the oil seal of the large and small arm safety relief valve is damaged, it will cause a certain leakage and will also cause the arm to fall.

5. Distributing the pump seal is not good, also known as “unloading”, then the seal of the distribution pump needs to be replaced.

6. Poor contact of the hydraulic pump proportional solenoid valve joint will also cause the arm of the large and small arms to fall off.

7. Seriously lost arm (oil temperature about 45 °C, 5 minutes tooth drop more than 95mm), most likely caused by the main valve being stuck.

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What should I do if the excavator loses its arm?

1. Check the temperature of the excavator working environment, whether there is any improper use of the hydraulic oil model, and whether the inferior hydraulic oil is used.

2. When the arm failure occurs, you can first reduce the boom pressure and carefully observe whether the boom is falling quickly.

3. Check whether there is any fault in the hydraulic cylinder and cylinder oil seal. If the oil seal is poorly sealed, it will leak oil. Replace the oil seal in time.

4. After replacing the oil seal, if the arm is still removed, check the distribution valve and the boom return oil safety valve.

BRAND MODEL PART NO. DESCRIPTION WEIGHT(KG) SPECIFICATION
CATERPILLAR 966 G General Purpose 1004044 Heavy Duty End 31 1-3/8 x 16x 51-7/8
CATERPILLAR 966 G General Purpose 1073287 Carbided NonRev CTR 107 1-3/8 x 12 x55-1/4
CATERPILLAR 966 G General Purpose 1073286 Carbided NonRev CTR 107 1-3/8 x 12 x55-1/4
CATERPILLAR 966 G General Purpose 1230336 Carbided NonRev END 23 1-3/8 x 8 x 18-1/4
CATERPILLAR 966 G General Purpose 1230337 Carbided NonRev END 23 1-3/8 x 8 x 18-1/4
CATERPILLAR 966 G General Purpose 1006666 Segment 21 1-3/16 x14-11/64 x 11-35/64
CATERPILLAR 966 G General Purpose 1406870 Heavy Duty Segment 25 1-3/8 x14-11/64 x 11-35/64
CATERPILLAR 966 G General Purpose 1744116 Half Arrow Segment
CATERPILLAR 966 G General Purpose 1615873 Rear Wear Plate 32 1-3/8 x 10x 22-1/4
CATERPILLAR 966 G Rock 1486915 Spade Base Edge 418 1-1/2x 24-1/4 x 128
CATERPILLAR 966 G Rock 1486935 Sidebars
CATERPILLAR 966 G Rock 1359294 Heavy Duty Segment 25 1-1/2x 13 x 11-13/16
CATERPILLAR 966 G Rock 1359295 Heavy Duty RH Segment 26 1-1/2x 13 x 12-3/8
CATERPILLAR 966 G Rock 1359296 Heavy Duty LH Segment 26 1-1/2x 13 x 12-3/8
CATERPILLAR 966 G Rock 1359544 Half Arrow Segment
CATERPILLAR 966 G Rock 1359545 Half Arrow Segment RH
CATERPILLAR 966 G Rock 1359546 Half Arrow Segment LH
CATERPILLAR 966 G Rock 6Y6351 Base Edge Wear Plate 69 1-3/8 x 10x 41-3/4
CATERPILLAR 966 G Rock 1618573 Rear Wear Plate 32 1-3/8 x 10x 22-1/4
CATERPILLAR 966 G Rock 1541604 Spade Base Edge 418 1-1/2x 24-1/4 x 128
CATERPILLAR 966 G Rock 1486934 Sidebars
CATERPILLAR 966 G Rock 1328241 Right Hand End 61 1-1/4 x14-1/4 x 34-13/16
CATERPILLAR 966 G Rock 1328243 Right Hand Center 46 1-1/4 x14-1/4 x 23-1/2
CATERPILLAR 966 G Rock 1328240 Center Blade 44 1-3/16 x14-11/64 x 51-7/8
CATERPILLAR 966 G Rock 1328244 Left Hand Center 46 1-3/16 x14-11/64 x 25-3/4
CATERPILLAR 966 G Rock 1328242 Left Hand End 61 1-3/16 x14-11/64 x 25-1/4
CATERPILLAR 966 G Rock 6Y6351 Base Edge Wear Plate 69 1-3/8 x 10x 41-3/4
CATERPILLAR 966 G Rock 1618573 Rear Wear Plate 32 1-3/8 x 10x 22-1/4
CATERPILLAR 970 G General Purpose 7I3631 Base Edge W/Seg Holes 240 1-1/2x 11-7/8 x 115-3/16
CATERPILLAR 970 G General Purpose 4V7175 RH Corner 1 Hole 9 1-3/8 x 10 x 9
CATERPILLAR 970 G General Purpose 4V7174 LH Corner 1 Hole 9 1-3/8 x 10 x 9
CATERPILLAR 970 G General Purpose 8E5310 RH Corner 2 Hole 15 2 x 8-3/4 x 10-3/4
CATERPILLAR 970 G General Purpose 8E5311 LH Corner 2 Hole 15 2 x 8-3/4 x 10-3/4
CATERPILLAR 970 G General Purpose 1U1909 Center Blade 88 1-3/16 x14-11/64 x 49-3/4
CATERPILLAR 970 G General Purpose 3G6395 End Blades 25 1 x 6-1/4 x 13-9/16
CATERPILLAR 970 G General Purpose 1073282 Carbided NonRev CTR
CATERPILLAR 970 G General Purpose 1073283 Carbided NonRev CTR
CATERPILLAR 970 G General Purpose 1230336 Carbided NonRev END 23 1-3/8 x 8 x 18-1/4
CATERPILLAR 970 G General Purpose 1230337 Carbided NonRev END 23 1-3/8 x 8 x 18-1/4
CATERPILLAR 970 G General Purpose 1006664 Segment 18 1-3/16 x14-1/4x 10.039
CATERPILLAR 970 G General Purpose 1406869 Heavy Duty Segment 21 1-3/16 x14-1/4x 10.039
CATERPILLAR 970 G General Purpose 9W6749 Rear Wear Plate 37 1-3/8 x 10x 22-1/4
CATERPILLAR 970 G General Purpose 9V6575 Base Edge W/Seg Holes 255 1-1/2x 12 x 119-3/4

9V0005 9U3748 9U4713 Caterpillar Loader Base Edges

9V4650, 9V-4650 CAT LOADER BLADES

9V6571 9V-6571 943 TRACK LOADER Bucket Base Edge

8R4649 9V3562 988B Loader Spade Nose Bucket Edge

Fabco Bucket Adaptor Weld-on 16L3BW-8-24, 2740W24

3C SERIES Fabco Fabricated Teeth

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1T3STT Keech Mini Digger Twin Pick Tooth

8340, 240 Standard Dirt Fabco Tooth Point

9V4650, 9V-4650 CAT LOADER BLADES

Cat Wheel Loader Base Edge 9V0009 9V-0009

8V7453 8V-7453 Cat Loader 943 Multi-Purpose Bolt-on Edge

8V9583, 8V-9583 WHEEL LOADER Welded-on Base Edge