In simple terms, motor graders are used to finish grade (refine, set precisely) the rough grading performed by heavy CE such as scrapers and bulldozers. A small motor grader within a range of 80-150 horsepower is usually enough for most jobs.Motor Grader Construction Equipment. A motor grader, sometimes called a grader or road grader, is a narrow multipurpose construction machine used to flatten a surface during grading projects. Differnce between buying and renting heavy machinery for rent is best way to reduce yearly expence. Generally speaking, the working principle of a motor grader is it uses its moldboard, or blade, for rough or fine grading.How much does a Motor Grader Operator make in California? The average Motor Grader Operator salary in California is $51,204 as of July 28, 2021, but the range typically falls between $42,404 and $62,504.