SunJoe MJ1800M - Reel Mower 18-INCH, 5-Position Cutting Height Manual
![]()
Safety Instructions
![]()
All Operators Must Read These Instructions Before Use
Always follow these safety guidelines. Failure to do so may result in serious bodily injury or death.
General Safety WARNINGS!
When using this reel mower, basic safety precautions should always be followed to reduce the risk of personal injury. These precautions include:
![]()
This unit can be dangerous! Careless or improper use can cause serious injury.
![]()
Risk of dismemberment: keep hands and feet away from the rotating blades and the cutting area.
Before using the reel mower, familiarize yourself with the controls, especially how to stop the mower in an emergency. The only individuals who should use the mower are those who thoroughly understand these instructions and know how to properly operate the unit. Children should never be allowed access to the mower.
Retain this manual for future reference and reread it at the start of each mowing season.
Safety Information
- Never place hands, fingers, or feet inside the reel. Although this mower is not powered by a motor, the reel spins when the wheels turn, and it is sharp enough to cause serious injury.
- Never mow when the grass is wet as it can be slippery.
- Do not use the reel mower while barefoot or while wearing sandals.
- Walk behind, never run, while using the reel mower. Always keep proper footing and balance when using this reel mower.
- Do not intentionally strike or hit trees, fences, or other objects. Doing so can cause severe injuries or permanently damage the reel mower's mechanisms.
- Make sure that the reel mower is in proper working order prior to use. Do not attempt to operate this reel mower if it is damaged. Contact your authorized Snow Joe ® + Sun Joe ® dealer or call the Snow Joe ® + Sun Joe ® customer service center at 1-866- SNOWJOE (1-866-766-9563).
![]()
Safety Instructions for Walk-Behind Reel Mowers
General Operation
- Read, understand, and follow all instructions on the machine and in the manual(s) before starting.
- Do not put hands or feet near or under the machine. Always stay clear of the discharge opening.
- Only responsible adults who are familiar with the instructions should be allowed to operate this machine.
- Clear the mowing area of foreign objects such as rocks, wire, toys, and other miscellaneous articles, which could be picked up and thrown by the rotating blades.
- Make sure that the mowing area is clear of bystanders before starting the mower. Stop the mower if anyone enters the area.
- Always look down and behind before starting and while moving backward with the mower.
- Do not operate the machine without safety protective devices in place and in proper working order.
- Never operate the mower on wet grass. Always be sure of your footing; walk, never run, with the mower.
- Keep blades sharp.
- Keep hands and feet away from the cutting area.
- Always wear eye protection when operating the machine.
- Objects struck by the reel mower blades can cause severe injuries. The mowing area should always be carefully examined and cleared of all objects prior to each mowing.
- Only use identical replacement blades.
Slope Operation
Slopes are major factors involved in slip and fall accidents. Such accidents can cause severe personal injury. Operating this mower on any inclined surface requires extra caution. If you feel uneasy on a slope, do not mow it.
- Mow across the face of a sloped surface; never mow up and down a slope. Exercise extreme caution when changing direction on a slope.
- Watch for holes, ruts, bumps, rocks, or other hidden objects. These may cause an unexpected slip or fall.
- Do not mow on wet grass or excessively steep slopes. Poor footing could cause a slip and fall accident.
- Do not mow near drop-offs, ditches, or embankments.
You could lose your footing or balance.
Children
Tragic accidents can occur if the operator is not alert to the presence of children. Children are often attracted to the mower and the mowing activity. Never assume that children will remain where you last saw them.
- Keep children out of the mowing area and under the watchful care of a responsible adult other than the operator.
- Stay alert and stop the reel mower if a child enters the area.
- Never allow children access to the machine.
- Use extra care when approaching blind corners, shrubs, trees, or other objects that may block your view of a child.
Service
- Keep all nuts and bolts tight.
- Never tamper with safety devices. Regularly check to ensure these devices are in place and in proper working order.
- Keep the reel mower free from grass, leaves, or other debris buildup.
- If you strike a foreign object, stop and inspect the reel mower. Repair, if necessary, before restarting.
- The mower blades are sharp. Wrap the blades or wear gloves when handling.
- Maintain or replace safety and instruction labels as needed.
Know Your Manual Reel Mower
Read the owner's manual and safety instructions carefully before operating the reel mower. Compare the illustration below to the reel mower in order to become familiar with the location of the various controls and adjustments. Save this manual for future reference.
![SunJoe - MJ1800M - Overview Overview]()
- Foam grip
- Upper handle frame
- Handle shield knobs (4)
- Handle shield
- Lower handle bar (2)
- Front wheel (2)
- Mower housing
- Rear wheel (2)
- Height adjustment lever (2)
- Lifting handle
- Steel blades
- Middle handle frame
- Allen wrench
Technical Data
Rotor | 5 steel blades | Wheel Size | Front: 10 in. (25 cm) Rear: 6 in. (15 cm) |
Cutting Width | 18 in (45.8 cm) |
Cutting Heights | 1.1 in. – 3.2 in. (2.7 cm – 8.2 cm) | Height Control | 5-position manual height adjustment |
Weight | 34.6 lbs (15.7 kg) |
Unpacking
Carton Contents:
- Reel mower body with front wheels
- Rear wheels (2)
- Rear wheel bolt + washer (2)
- Allen wrench
- Upper handle frame
- Middle handle frame
- Lower handle bar (2)
- Handle shield
- Handle shield knobs (4)
- Handle shield bolts (4)
- Manuals with registration card
- Carefully remove the manual reel mower and check to see that all of the above items are supplied.
- Inspect the product carefully to make sure no breakage or damage occurred during shipping. If you find damaged or missing parts, DO NOT return the unit to the store. Please call the Snow Joe® + Sun Joe® customer service center at 1-866-SNOWJOE (1-866-766-9563).
NOTE: Do not discard the shipping carton and packaging material until you are ready to use your new manual reel mower. The packaging is made of recyclable materials.
Properly dispose of these materials in accordance with local regulations.
![]()
The equipment and packaging material are not toys. Do not let children play with plastic bags, foils, or small parts. These items can be swallowed and pose a suffocation risk!
Assembly
Rear Wheel Assembly
- Align one rear wheel with the hole on the end of the mower body, and connect with one set of rear wheel washer + bolt, as shown (Fig. 1).
![SunJoe - MJ1800M - Rear Wheel Assembly - Step 1 Rear Wheel Assembly - Step 1]()
- Use the supplied Allen wrench to secure the bolt (Fig. 2).
![SunJoe - MJ1800M - Rear Wheel Assembly - Step 2 Rear Wheel Assembly - Step 2]()
- Repeat the above instructions for the other wheel.
Handle Assembly
- Lay out the handle parts upside down as shown for easier assembly. Make sure the arch of the upper handle frame is pointing down. Enter the end of the upper handle frame into the middle handle frame, and enter the end of the middle handle frame into the lower handle bar. Roughly align the holes (Fig. 3).
![SunJoe - MJ1800M - Handle Assembly - Step 1 Handle Assembly - Step 1]()
Operation
Cutting Height Adjustment
- The cutting height of the 18 in. (45.8 cm) reel mower can be adjusted from 1.1 in. to 3.2 in. (2.7 to 8.2 cm) by moving the 5-position height adjustment levers to the desired setting. The height adjustment levers are located next to the rear wheels.
- In order to set the mower to its lowest cutting position, hold the mower by its lifting handle, and pull the adjustment levers on both sides, one at a time, and set them to position A (Fig. 10).
- In order to set the mower to its highest cutting position, hold the mower by its lifting handle, and move the adjustment levers on both sides to position B (Fig. 10).
NOTE: The two adjustment levers MUST be set to the same position (height).
![SunJoe - MJ1800M - Cutting Height Adjustment Cutting Height Adjustment]()
- Other cutting heights are achieved by moving the adjustment levers to the settings between the highest and lowest positions.
Ensuring a Clean Cut
![]()
The steel blades are extremely sharp. To avoid injury, wear gloves while making adjustments. Keep fingers away from the interface between the cutting reel blades and stationary blade.
NOTE: Although the blades are pre-adjusted prior to leaving the factory, it is recommended that the adjustment be verified prior to first use.
NOTE: Vibrations during shipping can cause blade misalignment, which often causes the blades to become too loose or too tight. This will result in a rough, uneven cut, or make the mower difficult to push (Fig. 11).
![SunJoe - MJ1800M - Ensuring a Clean Cut - Step 1 Ensuring a Clean Cut - Step 1]()
- To verify if the blades make contact, place the mower on a firm level surface with blocks in the front of the rear wheels so the mower will not move during testing.
Raise the cutting height to the highest setting to improve access. - With the mower resting on all four wheels, slowly turn the cutting reel by lifting it upward, one blade at a time, through a full rotation or two. If you hear scraping or feel resistance, the blades are contacting each other and need adjustment (Fig. 12).
![SunJoe - MJ1800M - Ensuring a Clean Cut - Step 2 Ensuring a Clean Cut - Step 2]()
- Follow the instructions to adjust the mower blade.
- To check if the mower cuts properly, turn the mower on its side.
- Starting with the end close to the ground, feed a strip of paper between a cutting reel blade and the stationary blade, keeping the paper flush against the side of the stationary blade. About half an inch of the strip should be visible beyond the stationary blade.
- Slowly rotate the cutting reel toward the stationary blade, and observe whether the paper is cut as the first cutting reel blade passes (Fig. 13).
![SunJoe - MJ1800M - Ensuring a Clean Cut - Step 3 Ensuring a Clean Cut - Step 3]()
Adjusting the Mower Blades
- Each end of the cutting bar can be adjusted separately.
- The cutting bar blade, which is located under the reel, is able to pivot. The two adjustment screws located at the back of the mower move the cutting bar away from the blades when they are turned counterclockwise, and closer to the blades when they are turned clockwise (Fig. 15).
![]()
Do not overtighten the adjustment screws as this could damage the cutting bar. Both screws must be tight on final adjustment.
![SunJoe - MJ1800M - Adjusting the Mower Blades Adjusting the Mower Blades]()
- To loosen the blades, use the Allen wrench provided and turn both adjustment screws by an equal amount counterclockwise.
- To tighten the blades, tighten both screws by an equal amount by turning them clockwise.
NOTE: If you have any questions, please call the Snow Joe® + Sun Joe® customer service department at 1-866-SNOWJOE (1-866-766-9563) for assistance. - Once the mower blades have been properly adjusted and their alignment has been verified, you can now proceed to use your reel mower. Align the cutting path indication arrow with the previously cut path.
Mowing Tips
Follow the 1/3 Rule
The 1/3 rule is key to an enjoyable mowing experience and a healthy lawn.
- You should mow your lawn regularly, at least once a week, during the growing season.
- Be guided by observing the lawn and taking care not to remove more than 1/3 of the total height of the turf at any mowing session and never more than 1 inch at a time (Fig. 16).
![SunJoe - MJ1800M - Mowing Tips - Follow the 1/3 Rule Mowing Tips - Follow the 1/3 Rule]()
- Following this rule will stimulate the turf's root growth, maintain its health, and encourage its natural ability to crowd out unwanted weeds.
Tall Grass Requires Incremental Cutting
- For extremely tall grass, set the cutting height at the mower's maximum setting for the first pass, and then reset it to the desired height and mow a second or third time (Fig. 17).
![SunJoe - MJ1800M - Tall Grass Requires Incremental Cutting Tall Grass Requires Incremental Cutting]()
- Removing too much of the turf's height, especially in the heat of summer, can cause root shock and weaken the lawn; bringing down the height by successive mowing over two or more days can avoid this damage and maintain the health of the turf.
- If the lawn is overgrown (to higher than 4 inches) it may be necessary to use a brush cutter to remove the excess turf mass before resuming mowing at normal heights.
NOTE: Do not cover the grass surface with a heavy layer of clippings. Consider using a grass collection system and starting a compost pile.
Transporting the Mower
During normal operation, the blade reel will turn anytime the mower's front wheels are turning. To safely move the mower from one location to another without the blade reel turning, simply pivot the handle over the reel and push the mower from the opposite side. Pushing the mower in this manner (transport mode) prohibits the blade reel from turning (Fig. 18).
![SunJoe - MJ1800M - Transporting the Mower Transporting the Mower]()
Care + Maintenance
- Minimum care is required to ensure smooth operation of your mower.
- To avoid damage to the mower or cutting blades, keep the area to be mowed free from debris.
- For best results, regularly apply lubricant to the mower's cutting surfaces, cutting reel axle shaft, and wheels.
Sharpening the Cutting Blades
- Spread a thin layer of lapping compound on the front edge of the reel blades.
- Adjust the cutting bar so that the blade has light but firm contact across the full width of the bar.
![]()
Do not overtighten the adjusting screws, as this could damage the cutting bar. Tighten both screws during final adjustment. - Turn the reel blades until the front edge of the cutting bar blade is polished.
![]()
Clean any grinding compound or debris from the cutting bar blade, reel blade, pinions, and pawls.
NOTE: Use industrial or valve lapping compound between 100 and 240 grit.
NOTE: Lubricate the axle and pinion with a light film of wheel bearing grease.
Cleaning and Storage
- Clean the exterior of the machine thoroughly using a soft brush and cloth before storing. Do not use water, solvents, or polishes.
- Turn the mower on its side to clean the blade area.
![]()
Do not place your hands inside or near the cutting area. If grass cuttings are compacted in the blade area, remove them using a wood or plastic cleaning tool appropriate for blade cleaning. - Store the mower in a dry place. Do not place other objects on top of the mower during storage.
Maintenance Tips
Reel mowers are relatively low maintenance. For consistent cutting, follow the below instructions:
- Always keep the cutting bar properly adjusted. Refer to the instruction manual for further directions.
- Regularly clean and lubricate cutting edges with light spray oil.
![]()
Reel mowers have difficulty cutting tall weeds, such as dandelions, and will often bend, rather than cut, such weeds. Cut often to prevent this.
Service and Support
If your Sun Joe® MJ1800M manual reel mower requires service or maintenance, please call the Snow Joe® + Sun Joe® customer service center at 1-866-SNOWJOE (1-866-766- 9563).
Model and Serial Numbers
When contacting the company or reordering parts, you will need to provide the model and serial numbers of your product. These are found on the decal affixed to the housing of your reel mower. Copy these numbers into the space provided below.
![]()
![]()
Documents / ResourcesDownload manual
Here you can download full pdf version of manual, it may contain additional safety instructions, warranty information, FCC rules, etc.
Download SunJoe MJ1800M - Reel Mower 18-INCH, 5-Position Cutting Height Manual
Need help?
Do you have a question about the MJ1800M and is the answer not in the manual?
Questions and answers