Trail Mower

We use lawn mowers to control vegetation that tries to cover the local national forest trails. The mower is run along both sides of the trail (versus down the middle of the trail) to cut back growth. They can be run in either mulch mode, or side discharge (mow down the left side so debris is placed on the trail). There are a lot of lessons-learned, shared here. Key lessons include: Select a light weight, rear-wheel drive mower, with tall rear wheels. The Toro model 20340 works well. The gas cap needs to be secured so it does not get pulled off by vegetation while mowing. Air filter cover needs to be more secure. Install a carburator shield to protect it from branches. Need a spark arrestor. Add a deflector to the front to keep vines from getting caught in the front wheels. Also add a handle so helpers can pick the front of the mower over logs and not put their fingers inside the blade area. The stock gas tank vent can release gasoline when mower is tilted forward. Upgrade the cable that engages the rear wheels where it attaches to the handle.
Gas Cap Modifications Screw a coax clamp on the side of the gas cap. Then use a bungie cord to hook the coax clamp. The bungie is tied off where it won't interfere with the cable to kill the motor.
Air Filter Modifications The cover over the air filter can get caught by brush and pulled off. Reinforce with a thru bolt: Remove air filter cover and air filter. You will see 4 bolts. Remove top left bolt and replace with a M5-80x50 bolt, screwing it in from the back. New long bolt screwed in from back. Drill a hole in the air filter cover so the bolt pokes out. Secure with M5-80 nylon insert nut.
Carburetor Shield Shield for the carburetor is just a piece of sturdy plastic duct taped to the shroud.
Spark Arrestor The Forest Service requires a spark arrestor to mow in the forest.
Front Wheel Shield and Handle The deflector shield for the front wheels is a piece of oak cut long enough to extend to the outside of the front wheels. A handle is added to make it easier to pick the front of the mower up when crossing First, remove the existing bumper. There are a couple of star screws in the front. Cut a piece of 3/4" thick oak to 23" long and 3-1/2" tall. Round off the front edges. Drill 3/8" hole through board and front of mower. Attach board using 5/16" lag screws, spacers and locknuts w/ washers. A handle is screwed to the top.
Gas Tank Vent There is a vent from the gas tank to the air filter area. If you tilt the mower forward too much, gas streams out!!! There are valves designed for chainsaws to only let air into the gas tank, but gas can't leak out. Sometimes these valves don't let enough air in. So every once in a while, crack open the gas lid to let air in. Otherwise the vacuum means no fuel flow to the carburetor.
Drive cable The drive cable on every Toro we have used has broken where it attaches to the handle. This is quite a hassle if you are deep in the forest, several miles from your car.

Revised: 16 August 2020