The Brantly LD6 & MD8 Backhoes are operator-controlled implements designed for various digging and earth-moving tasks, including trenching, grave digging, and general excavation. These backhoes are compatible with a range of tractors, with the LD6 model designed for tractors ranging from 12 to 24 horsepower, and the MD8 model accommodating a broader range of applications due to its increased digging capabilities.

Function Description:

The backhoes operate through a hydraulic system, controlled by a two-lever system that allows the operator to manipulate the boom, dipper arm, bucket, and stabilizers. The primary functions include:

Digging: Excavating soil using the bucket, dipper arm, and boom.
Trenching: Creating continuous trenches, bellholes, and side slopes.
Dumping: Discharging excavated material from the bucket.
Stabilization: Using hydraulic stabilizers to secure the backhoe during operation and prevent tipping.
Backfilling: Returning excavated soil to a trench or hole.

The control levers are designed for intuitive operation, relating movements to the operator's seated position. For example, moving the boom lever to the left swings the boom left, and pushing the bucket lever to the left curls the bucket inward ("Fill").

Important Technical Specifications:

LD6 Backhoe:

Digging Depth (2 Ft. Flat Bottom): 6 Ft. (182.9 cm)
Digging Radius: 9 Ft. (274.3 cm)
Bucket Clearance (60° Rotation): 49.5 In. (125.73 cm)
Bucket Clearance (40° Rotation): 62.0 In. (157.48 cm)
Max. Power: 72.0 In. (182.88 cm)
Swing Radius: 135 Degrees
Controls: 4 - Lever
Transport Height: 6 Ft. (182.9 cm)
Stabilizer Spread (Transport): 48 In. (121.92 cm)
Digging Force (With Bucket Cylinder): 3000 Lbs.
Digging Force (With Dipper Cylinder): 1560 Lbs.
Hydraulic Operating Pressure: 1800 P.S.I
Hydraulic Flow Requirements: 4.0 G.P.M
Hydraulic Fluid Type: Type "F"
Hydraulic System Capacity: 10 Qts.
Cylinder Sizes:
- Boom: 2.0 x 22 ½ x 1 ½
- Crowd (Dipper): 2.0 x 16 x 1 ½
- Bucket: 2.0 x 10 x 1 1/8
- Swing: 2.5 x 6 x 1 1/8
- Stabilizer: 2.0 x 10 x 1 1/8
Cycle Times:
- Bucket Open: 3.0 sec.
- Bucket Closed: 3.5 sec.
- Dipper Open: 2.5 sec.
- Dipper Closed: 3.0 sec.
- Boom Up: 6.0 sec.
- Boom Down: 4.5 sec.
- Boom Right: 3.0 sec.
- Boom Left: 3.0 sec.
Bucket Options (Width, No. Teeth, Capacity, Weight):
- 615-1: 8", 2 teeth, .50 cu. ft., 30 Lbs.
- 615-2: 13", 3 teeth, 1.0 cu. ft., 48 Lbs.
- 615-3: 16", 3 teeth, 1.25 cu. ft., 56 Lbs.
Shipping Weight (Backhoe only): 500 Lbs.
Shipping Weight (Mounting Kit): 225 Lbs.
Shipping Weight (6 Ft. Backhoe with Mtg. Kit): 725 Lbs.

MD8 Backhoe:

Digging Depth (2 Ft. Flat Bottom): 8.0 Ft. (243.84 cm)
Digging Radius: 11 Ft. (340.36 cm)
Bucket Clearance (60° Rotation): 57.25 In. (145.41 cm)
Bucket Clearance (40° Rotation): 78.0 In. (198.12 cm)
Max. Power: 96.0 In. (243.84cm)
Swing Radius: 135 Degrees
Controls: 4 - Lever
Transport Height: 7 Ft. (213.36 cm)
Stabilizer Spread (Transport): 48 In. (121.92 cm)
Digging Force (With Bucket Cylinder): 4200 Lbs.
Digging Force (With Dipper Cylinder): 2280 Lbs.
Hydraulic Operating Pressure: 1800 P.S.I
Hydraulic Flow Requirements: 4.0 G.P.M
Hydraulic Fluid Type: Type "F"
Hydraulic System Capacity: 12 Qts.
Cylinder Sizes:
- Boom: 2.5 x 22 ½ x 1 ½
- Crowd (Dipper): 2.0 x 22 ½ x 1 ½
- Bucket: 2.0 x 16 x 1 ½
- Swing: 2.5 x 6 x 1 1/8
- Stabilizer: 2.0 x 10 x 1 1/8
Cycle Times:
- Bucket Open: 3.5 sec.
- Bucket Closed: 4.5 sec.
- Dipper Open: 4.0 sec.
- Dipper Closed: 5.0 sec.
- Boom Up: 6.5 sec.
- Boom Down: 5.0 sec.
- Boom Right: 3.0 sec.
- Boom Left: 3.0 sec.
Bucket Options (Width, No. Teeth, Capacity, Weight):
- 818-1: 8", 2 teeth, .75 cu. ft., 38 Lbs.
- 818-2: 13", 3 teeth, 1.5 cu. ft., 52 Lbs.
- 818-3: 16", 3 teeth, 2.0 cu. ft., 64 Lbs.
Shipping Weight (Backhoe only): 700 Lbs.
Shipping Weight (Mounting Kit): 225 Lbs.
Shipping Weight (8 Ft. Backhoe with Mtg. Kit): 925 Lbs.

Usage Features:

Safety First: Emphasizes reading the operator's manual, using handholds, replacing decals, and observing proper maintenance. Crucially, it warns against operating the backhoe as a personal hoist or work platform and stresses operating only when seated at the controls. Tractor safety precautions include using a roll bar and seat belt, avoiding operation in enclosed spaces, and securing the unit on inclines.
Installation: The backhoes are shipped partially assembled, requiring the operator to install the main frame, boom, dipper arm, and bucket. Detailed instructions are provided for each step, including torque specifications for bolts.
Hose Assembly: Specific routing and connection instructions for hydraulic hoses are provided to prevent chafing and ensure proper function.
Digging Techniques: Guidelines are given for efficient digging, including filling and dumping the bucket, maintaining a level trench bottom, and techniques for trenching in various scenarios (continuous, between buildings, side slopes).
Weighting and Counterweighting: The backhoes require a front loader or front blade to lift the front wheels for proper balance. Stabilizers should be set to remove weight from the rear wheels.
Grave Digging: Specific instructions for positioning the tractor and digging in the middle of the grave, taking shallow bites, and finishing end walls. Recommends using a platform in sandy soil to prevent cave-ins and creeping.
Backhoe Removal and Storage: Instructions for safely detaching the backhoe from the tractor, storing it, and preparing the tractor for independent operation.

Maintenance Features:

Regular Maintenance: Stresses that regular maintenance is key to long equipment life and safe operation.
Every 8 Hours of Operation:
- Thoroughly grease all swivel points (ram and base end of all cylinders). Specific lubrication points are listed for the Swing Shaft Assembly, Stabilizer Assembly, Boom Assembly, Crowd Cylinder, Dipper Assembly, and Bucket Cylinder.
- Perform a thorough visual check for signs of wear, leakage, loose fittings/pins.
Every 40 Hours of Operation:
- Check hydraulic reservoir fluid level and refill as needed. Inspect all lines, fittings, and control valve for leaks.
- Physically check all pins, cotter pins, and nuts for wear or loose fit. Tighten or replace as necessary. Clean equipment of dirt, oil, and grease.
Every 200 Hours of Operation:
- Drain and replace hydraulic oil with clean fluid.
- Check pressure relief valve operation using an in-line pressure meter. The relief valve should open at 1800 P.S.I. (1750-1850). Instructions for adjusting the relief valve are provided, with a warning not to set the pressure higher than specified to prevent damage and personal injury.
Pre-Delivery Checklist: A checklist for dealers to ensure the backhoe is ready for operation, including hydraulic system oil level, lubrication, removal of paint from cylinder rods and valve spools, control handle operation, cylinder purging, hydraulic connection checks, control valve relief pressure, and backhoe attachment bolts.
Warranty: Emphasizes that the warranty registration card must be filled out and returned with pressure, flow, and performance information to validate the warranty.

BMC LD6 - Page 48

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