How to Fix a Mower Deck that Streaks

What You'll Need
Lawnmower blade sharpener or round metal file
Adjustable wrench or pliers
Safety glasses
Electric tape

Your mower deck has been giving you excellent service for some years now. With time, though, all things become less reliable and less able to do their job. This is not any different for a mower deck. There are several issues that can happen to a mower deck device including streaks being left in the grass. A few tools and some safe procedures will get your mower deck back into good working order in a short amount of time.

Step 1:  Safety First

A mower deck is a dangerous piece of garden and lawn equipment. Be sure that before you do any maintenance to the mower deck there is no way for power to be fed to the blades. If your mower deck is equipped with an exposed spark plug the safest method to eliminate danger is to unplug the connector from the spark plug and cover with some electric tape to keep the spark plug from making contact. Also make sure that the gas tank is empty as well, to reduce the occurrence of spillage.

Step 2:  Inspect Your Mower Deck

Look at the under side of your mower deck at the blades. If you see any nicks or flaws in the mower blade this can cause your problems with streaking. Put on your safety goggles and gloves. Use the mower blade sharpener or the round file to sharpen the blades. If you do not wear safety devices you could get metal shavings in your eye, or slivers in your hands. It is always better to be safe. If your blades are cracked or warped then it is time to replace the blades.

Step 3:  Clean the Undercarriage of the Mower Deck

If an excess of grass gets built up underneath the mower around the blades then the mower will not properly do its job. Wearing gloves, use the scraper to remove any excess grass. If the grass is dry it will scrape off easily. If the grass is wet, which is usually when it sticks to the mower the job may be messier, but not difficult.

Step 4:  Adjusting Your Mower Deck

If you have used your mower for a couple years the deck may have become uneven. This will keep your mower blades from evenly cutting the grass and can cause streaking in the cut. Use pliers or an adjustable wrench to adjust each wheel until the mower deck is even on the ground. Many have markings to ensure that each wheel is adjusted the same. 

Step 5:  Scalping

Another way that streaks can occur in your grass is scalping. When your ground is not level and your mower is adjusted too low then your grass will begin scalping, or showing grass in some areas and shaved ground in high areas. The streaks show up well. Adjust the mower deck higher to give an appearance of level ground.

Step 5:  Engine Speed

If your mower engine runs slow you can get streaks from the blades not moving fast enough to cut evenly. Run high speed to reduce this problem.