Motor graders are a vital part of a wide range of construction projects. They do hours of heavy-duty work that inevitably results in wear and tear.
Routine equipment maintenance involves time and effort but it pays off. Maintenance significantly reduces the risk of damage to equipment, costly repairs and unplanned downtime.
In this article, we cover how to maintain a Caterpillar motor grader to keep it operating at maximum efficiency for optimal productivity and operator safety.
A structured approach to equipment maintenance
A structured, methodical approach is the best way to ensure that maintenance is done properly and on time. Use this approach to ensure nothing gets overlooked or neglected.
Visible schedule
Create a regular maintenance schedule and ensure it’s posted somewhere visible. All team members must be aware of their responsibilities and any potential downtime.
The schedule should include how often to change air filters, how frequently to lubricate grease points, how often to do visual inspection walkarounds and other vital maintenance.
Proactive maintenance
Also be proactive about maintenance on a daily basis. Operators should be able to identify issues or warning lights and report them so that faults get fixed quickly and don’t become bigger problems.
Do daily inspections
Daily inspections are a good way to ensure no issues go unnoticed. Operators must know how to conduct a pre-operation walkaround and how to identify potential maintenance issues.
Keep records
All maintenance, including ad hoc repairs, must be recorded. Make a note of any future maintenance needs, such as a part that’s wearing down and will need to be replaced soon.
Know your grader
Owners, managers and operators must be familiar with any operation or maintenance manuals or handbooks for the graders.
Knowing how the grader operates – and especially how it feels – makes it easier to identify when something is wrong.
Servicing schedule for Cat graders
A grader under heavy, prolonged use in harsh conditions obviously needs more TLC than a grader that’s being used lightly. Generally, maintenance work can be divided into daily, weekly and monthly tasks. An inspection checklist can help with this.
Daily maintenance is every day visual inspections of the machine. Check the motor grader blade, electrical components and fluid levels. Make sure the grader is handling as normal during operation.
Weekly maintenance includes checking your hydraulic system, replenishing fluid levels, inspecting the tyre tread and pressure, and adjusting loose blade handles. Schedule any necessary parts replacements.
Monthly maintenance will be changing air filters, replacing fluids and other damaged components. Check wear and tear on parts compared to the life expectancy in the manufacturer’s guidelines.
Motor grader maintenance tips
The blade/moldboard
This is the part that engages directly with the soil. Special attention must be given to its cutting edge.
Wear and tear on the cutting blade, or blades, attached to the moldboard is high, especially if the blade is pitched back, rather than at right angles.
This is why blades need to be inspected regularly (and replaced when necessary). Depending on the surface being prepared, blades should be checked after every 25 to 50 hours of operation.
If the blade gets too worn down before it’s replaced, the moldboard will be compromised. If you fail to maintain the blade’s edges and the bolts that keep them in place, you may end up needing to replace the moldboard.
To avoid undue wear or damage to the blade, never manoeuvre the grader with the blade on the ground (when not grading). Always raise it first.
Scarifiers
Standard on some machines and optional on others, these lessen the work of the moldboard for rough grading or cut-outs.
The “teeth” of the scarifier shouldn’t wear down to the point of reaching the scarifier shank, or pocket. If that happens, you’ll have to replace the shank − a far costlier task than replacing the teeth.
Never make sharp turns with the ripper or scarifier teeth in the ground. This could bend or break the teeth.
Blade slide and turntable
The blade slide allows the moldboard to move on a swivel track. It should be checked every month. The bronze or metal shim glides that control the blade slide’s movement can also wear down.
Fortunately, removing and replacing the glides, which are situated on four different points and should all be replaced simultaneously, is a quick and easy process.
To ensure your machine gives you the fine cut you want, the brushings in the slide can’t give too much play. If the slide’s movement is too loose, the clevis pins keeping it in place must be replaced.
Differential
To prevent damage to the differential, don’t engage the differential lock control at high speeds and never turn the machine with the differential lock engaged.
Also, do not engage the differential lock control while one wheel is spinning. The operator should decrease the engine RPM until the wheel stops spinning.
A good operator will be able to anticipate using the differential lock before wheel slippage occurs.
Tyres
Tyre traction affects the machine’s grade, so tyre pressure needs to be carefully monitored. The tyre tread is essential to the machine getting “good bite” on the ground. A half-inch deep is the absolute minimum for a grader’s tyre tread.
Air filters
If dirt clogs your machine’s air filters, their efficacy will be compromised and the motor grader will consume more fuel.
Check your air filters as per manufacturer recommendations and keep an eye on the “restricted alert” signal, if your machine has one, which alerts you to problems with airflow. Pre-filters do a good job of reducing the amount of dirt that enters the air filter, so they can be fitted to prevent you having to change the air filter as often.
Remember, the dustier your worksite, the harder your filters will be working, so you may need to replace them more regularly.
Operator station and controls
To ensure precision and operator safety, the seatbelt, floor mat and handles should be checked regularly. Loose blade handles will make jobs more difficult, especially where precise work is called for.
Also keep the windows clear from dust and dirt to improve visibility and prevent accidents.
Other checks to perform
In addition to the points above, general maintenance includes keeping an eye on the hydraulic cylinder, checking all seals, greasing and lubricating, and regularly checking for any suspicious leaks or drips.
Exercise caution when driving the grader over previously graded ground for a second pass. Uprooted material may cause damage to the tyres or underside of the grader.
At the KH Plant, we offer full rebuilds of Caterpillar 140G, 140H and 140K motor graders to like-new condition. We also offer component rebuilds and sales of reconditioned CAT graders. Contact us to learn more or with any questions about how to maintain a Caterpillar motor grader.
