| [Image: drawbar hitch] |
| [Image: sleeve hitch] |
| [Image: 3-point hitch] |
Implements, including mower decks, can be attached to tractors in several ways and in several locations.
They can be mounted under the tractor, as are most mower decks; on the rear of the tractor, typical for tillers; on the front of the tractor, typical for snow blowers; and on the tractor frame, as is done with front-end loaders. There are some standardized ways of mounting implements to the rear of the tractor.
Drawbar hitches are very simple and are found on everything from a lawn tractor on up (Figure 1). The tractor component can be as simple as a piece of steel plate turned up to form a horizontal surface with a hole in it. The implement tongue ends in a generally U-shaped or clevis structure that fits over (above and below) the tractor plate. A pin is then dropped through holes in all three pieces. This type of hitch is quite adequate for simple tasks such as pulling garden carts or fertilizer spreaders.
Sleeve hitches are seldom used now (Figure 2). They consist of a one-point hitch system in which the implement can be lifted by a manual lift arm, hydraulics or an electric linear actuator. The tractor portion of the hitch is a U-shaped steel frame with a small steel tube welded inside at the rear. The implement portion looks much like an drawbar hitch. It fits over the bracket and tube, and a hitch pin is then dropped through the holes in the implement hitch and the vertical tube. The entire U-shaped frame is then rotated up to lift the implement. Only implements designed for a sleeve hitch can be used.
Three-point hitches are the top-of-the-line system (Figure 3). They are found only on the larger tractors. They are nearly always actuated by hydraulics. This is the same system used on farm tractors. Garden tractors, if they have a 3-point hitch, will have a "category 0" hitch; compact tractors use a "category 1" hitch. ASAE (now ASABE) standards define the dimensions of the tractor hitches and matching implement components for each category. The hitches consist of two lower hitch arms that are roughly horizontal when lowered, but the outer ends of which rotate upward when the lift is raised. The third arm is not power-lifted. It is just a link fastened to the rear of the tractor and to the hitch mast on the implement. The upper link is a turnbuckle that can be screwed in or out to level the implement.
Again, only 3-point hitch implements can be used with this system, and category 0 and category 1 implements are not interchangeable. Most 3-point hitches include sway links - turnbuckles that can be tightened to eliminate side sway of the implement. Since small 3-point hitch implements seldom conform closely to ASAE standards, it is handy to be able to adjust the sway links to compensate for differences in width between the implement lower hitch pins.
Other implements are mounted on special hitches or brackets, specific to a manufacturer and model. Most center-mounted mowers on larger tractors are mounted with some kind of quick-attach system. Different manufacturers use different systems, but most allow the front bracket to be released easily from the front of the tractor, then the front bracket can be removed from the mower, the rear bracket loosened and the mower deck pulled out to the side after the drive is disconnected.
Some manufacturers offer their own quick-hitch system for front-mounted implements such as snow blowers and blades; other manufacturers just bolt the implements to the front of the tractor. Front-end loaders often mount onto quick brackets that are first bolted to the tractor frame.
In summary, the larger the implement and tractor, the more likely an upscale, easy-to-use hitch will be provided. Naturally, the upscale hitch systems cost more.