1. Introduction
This manual provides essential information for the safe and effective use, installation, and maintenance of your perfektGarten 48 cm lawnmower blade. This blade is designed as a 3-in-1 combination blade, suitable for ejecting, catching, and mulching functions on compatible Murray lawnmowers.
Our blades are manufactured from certified high-quality steel (50CrV4), sharpened, hardened, balanced (45HRC), and precisely curved to ensure a fine cut and extended service life, typically lasting a minimum of three seasons.
2. Safety Information
WARNING: Lawnmower blades are extremely sharp and can cause severe injury. Always handle with extreme care and wear appropriate protective gear, including heavy-duty gloves, eye protection, and sturdy footwear, when handling, installing, or maintaining the blade.
- Always disconnect the spark plug wire or remove the battery from electric mowers before performing any work on the blade.
- Ensure the engine is cool before handling the blade.
- Never attempt to sharpen or balance the blade without proper tools and knowledge. Consult a professional if unsure.
- Keep hands and feet away from the blade at all times, especially when the engine is running.
- Store the blade in a safe place, out of reach of children and pets.
For additional safety guidelines, please refer to the official safety information document: Safety Information (PDF).
3. Installation and Compatibility
This blade is compatible with specific Murray by Briggs & Stratton lawnmower models from 2005 onwards. It is crucial to verify the dimensions of this blade against your original blade to ensure proper fit and safe operation. This blade is not suitable for all lawnmowers equipped with a B&S (Briggs & Stratton) engine.
Image: Important Compatibility Notice. This image displays a warning stating that the blade is not suitable for all Briggs & Stratton equipped mowers and emphasizes comparing dimensions with the original part.
3.1. Verifying Blade Dimensions
Before installation, carefully measure your existing blade and compare it with the specifications provided below. Refer to the diagram for measurement points.
Image: Blade Dimension Diagram. This diagram illustrates the key measurement points for the lawnmower blade, including Length (L), Center Hole (ZB), Outer Hole (AL), Distance between outer holes (AB), and Width (B).
- Length (L): 480 mm
- Center Hole: 10.4 mm
- Outer Hole (AL): 10 mm
- Distance between center and center of outer bore (AB): 48 mm
- Width (B): 53 mm
- Thickness: 4 mm
3.2. Compatible Murray Models (from 2005 onwards):
- 881548 - MPH625E, 625 Series 19"
- 881549 - MXM500, 500 Series 19"
- 881550 - MXMH500, 500 Series 19"
- 881551 - MX500E, 500E Series 19"
- 881552 - MXMH575EX, 575EX Series 19"
- 881553 - MXMH625E, 625E Series 19"
- 881554 - MXTH675EX, 675EX Series 19"
- 881557 - MXMH850EX, 850E Series 19"
- 881560 - MXMU19675E, 675 Series 19"
- 881022 - MP500, 5TP 19"
- 881023 - MX550, 5.5TP 19"
- 881024 - MPH550, 19"
- 881025 - MXH550, 5.5TP 19"
- 881026 - MXH675, 6.5TP 19"
- 881027 - MXM550, 5.5TP 19"
- 881028 - MXTH675, 6.75TP 19"
- 881029 - MXMH625, 6.25TP 19"
- 881030 - MPH625, 6.25TP 19"
- 881031 - MXH650, 6.5TP 19"
- 881153 - MXMH650E, 19"
- 881154 - MXMH850E, 8.5TP 19"
- 881164 - MX500, 5TP 19"
- 881165 - MXMH850E, 8.5TP 19"
- 881243 - MXTH675, 6.75TP 19"
- 881272 - MXMH55, 5.5TP 19"
- 881403 - BT19550FC, 19" 5.5 GT
3.3. Installation Steps (General Guidance)
- Prepare the Mower: Ensure the lawnmower is turned off, the spark plug wire is disconnected (for gasoline mowers), or the battery is removed (for electric mowers). Allow the engine to cool.
- Secure the Mower: Tilt the mower onto its side with the carburetor facing upwards to prevent fuel leakage. Block the wheels to prevent movement.
- Remove Old Blade: Using a wrench, carefully loosen the blade bolt(s) holding the old blade in place. You may need a block of wood to prevent the blade from turning. Remove the old blade and any washers or spacers, noting their orientation.
- Clean Blade Area: Clean any grass clippings or debris from the blade mounting area.
- Install New Blade: Position the new perfektGarten blade, ensuring the cutting edge faces the correct direction (usually indicated by an arrow or curve on the blade). Reinstall any washers or spacers in their original orientation.
- Tighten Blade Bolt: Hand-tighten the blade bolt(s), then use a torque wrench to tighten to the manufacturer's specified torque setting for your mower model. Refer to your lawnmower's owner's manual for the correct torque.
- Check Balance: After installation, check the blade's balance. A properly balanced blade will spin freely without wobbling.
- Reconnect Power: Reconnect the spark plug wire or battery.
- Test: Start the mower in a safe, clear area and listen for any unusual vibrations or noises.
Always consult your specific lawnmower's owner's manual for detailed, model-specific installation instructions and safety precautions.
4. Usage Guidelines
The perfektGarten 48 cm blade is a 3-in-1 combination blade, designed for versatility in lawn care. It supports:
- Ejecting: For discharging grass clippings to the side or rear.
- Catching: For collecting clippings into a grass bag.
- Mulching: For finely cutting and recirculating clippings back into the lawn as natural fertilizer.
Ensure your lawnmower is set to the appropriate mode (if applicable) for the desired cutting function. For optimal performance, avoid mowing wet grass and ensure the cutting height is suitable for your lawn type.
5. Maintenance
Regular maintenance of your lawnmower blade ensures a clean cut, extends the blade's lifespan, and maintains mower efficiency.
- Cleaning: After each use, disconnect the spark plug wire/remove battery and clean grass clippings and debris from the blade and underside of the mower deck. This prevents buildup that can affect blade balance and cutting performance.
- Inspection: Regularly inspect the blade for signs of wear, damage, or dullness. Look for nicks, bends, or cracks. A dull blade tears grass, leading to an unhealthy lawn.
- Sharpening: The blade is designed to maintain sharpness for a minimum of three seasons under normal use. If the blade becomes dull, it can be sharpened. Sharpening should be done by a qualified professional or with appropriate tools to maintain the correct angle and balance. Improper sharpening can lead to an unbalanced blade, causing excessive vibration and potential damage to the mower.
- Replacement: Replace the blade if it is severely bent, cracked, or excessively worn. Even minor damage can lead to an unbalanced blade, which can damage the mower's engine or deck.
Image: perfektGarten 48 cm Lawnmower Blade. This image shows the full view of the perfektGarten 48 cm lawnmower blade, highlighting its design and cutting edges.
6. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Poor Cut Quality (torn grass) | Dull blade, incorrect blade installation, mowing wet grass. | Sharpen or replace blade. Ensure blade is installed correctly. Mow only dry grass. |
| Excessive Mower Vibration | Unbalanced blade (bent, damaged, or improperly sharpened), loose blade bolt. | Inspect blade for damage; replace if necessary. Ensure blade is properly balanced. Tighten blade bolt to specified torque. |
| Blade Not Spinning Freely | Obstruction under deck, blade bolt overtightened, incorrect blade size. | Clear obstructions. Check blade bolt torque. Verify blade dimensions against original. |
If troubleshooting steps do not resolve the issue, consult a qualified service technician or contact perfektGarten customer support.
7. Product Specifications
- Model Number: 139
- Blade Length (L): 480 mm
- Center Hole Diameter: 10.4 mm
- Outer Hole Diameter (AL): 10 mm
- Distance between center and center of outer bore (AB): 48 mm
- Blade Width (B): 53 mm
- Blade Thickness: 4 mm
- Material: Certified high-quality steel (50CrV4)
- Hardness: 45 HRC
- Blade Type: 3-in-1 Combination (Eject, Catch, Mulch)
- Compatible Mowers: Murray by Briggs & Stratton models from 2005 onwards (refer to section 3.2 for specific models)
- Product Dimensions (L x W x H): 48 x 5 x 3 cm (packaging/overall)
- Power Source Compatibility: Fuel-powered (for compatible mowers)
8. Warranty and Support
For warranty information or technical support regarding your perfektGarten lawnmower blade, please contact the manufacturer or your retailer. Ensure you have your product model number (139) and purchase details available when contacting support.
While specific warranty details are not provided in this manual, perfektGarten blades are designed for durability and performance, typically lasting a minimum of three seasons under proper use and maintenance.