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Jacobsen Mower PicturesHere is my new (used) Jac mower, probably from the late 80's early 90's. It has a lot of miles on it, but is rust ree and had been refurbished with a new Honda 3.5 HP motor. The reels were recently sharped and have lots of life (height is ground away over time) left. The bedknife is properly set and and all the seals and gaskets in good condition. The only thing missing is the cover to the clutch compartment. There is a part on the clutch that looks worn. Let me try and describe how this baby works. The honda moter on top (this should last a long time ... Honda is very good quality) ... and has a drive rod comig out of the middle (I'm not really technical/mechanical .. so don't quote me on the names of parts). The moter starts just like any standard lawnmower with a Start/Stop Switch, a Fuel control lever, a pull starter, and a throttle lever (which is broken .. but not terribly necessary since you don't want to go very fast on a small green .. you want to have mower control). The drive rod comes out sideways and dissapears into chain drive assembly on the right side of the machine. First you start up the mower with the pull start. Then when you have moved to the green. You engage the clutch with a lever arm on the handle. This moves the shoe of the clutch into contact with the rod and starts transfer of power from the engine to the drive and reel unit. There is a small lever on the lower right hand side that engages or disengages the reel from spinning. When you want to drive the mower to a far destination .. disengage the reel and the mower will self propel (drive) when you engage the clutch. When you have arrived at the green. Re-enable the reel and when you engage the clutch, the mower moves forward and the reel spins .. cutting the grass. It is a little awkward to control at first, but the heavy weight of the front and rear rollers (which is split and spins 2 ways for turning) does a nice job of focusing the power of the cut downward to avoid hopping and skipping caused by your jumpy clutchwork. The mower has an easily removed and emptied catch bin. That's pretty much all there is to it. There is a set of adjustment screws for the bedknife/reel contact, and two large (hand) screws for height adjustment. Finally, there is a handy jack on the back of the machine for raising up the unit and working on the underside. Be careful and disconnect everything before working underneath .. these machines are razor sharp when properly setup.  Setting the height of the Jac is a breeze ... but there is a technique involved that you can use with any reel mower. Unlike rotary mowers, there are no "gauges" or "height settings" marked on the machine. You also cannot "eyeball" the height ... as tiny fractions of a turn of the knobs can change heights on either side dramatically. Ideally, both sides will be set perfectly at the same height. Here is how you do it.  You need a measuring bar, which is really nothing more than a long straight bar with a screw coming out of it. You lay the bar across the front and rear rollers of the mower and screw the screw into the bar until it snags the edge of the bedknife bar (the flat black bar that runs along the bottom of the mower). When the bar is tight in this position, carefully remove ... measure the height of the screw from the bar to the bottom of the screw head. This is your effective cutting height. Measure the other side and make sure it is the same. adjusting with small turns of the adjustment knobs. Remember .. if you are lowering your cutting height .. go very slowly and in small increments .. otherwise you will scalp/shock/kill your turf. Record your height settings (usually down in decimal format and often described using the metric scale) and experiment with different heights and results on your green.  I recently backlapped my trusty old Qualcast Mower. Here is how I did it. I spread 120 grit grinding compound (available at automotive dealers or lawnmower equipment companies or at R&R Products (see the Gear Page). spread evenly over the edge of all the reel. Then lower the reel onto the bedknife evenly on both sides .. It should be very difficult to turn the reel. Most reels can be accessed thru a side panel. Mine has a bolt on the side that I can attach to my power drill. Using a drill, grinder, or ratchet ... crank the reel in a backwards direction as fast as you can. This will take 15-30 minutes depending on how much power you have. Eventually, the reel will grind down evenly and you will no longer hear any noise from the grinding compound. As a final check .. the reel should be able to cut a piece of newspaper when you put it through the reel/bedknife. Remember it should cut .. not pinch off. That is what you want the reel to do to the bentgrass surface .. cut ... not pinch the blades of grass. Here is a link to the Jacobsen Website: Jacobsen Backyard Putting Green Construction Manual Copyright © 1998 Leo Melanson Putting-Greens.com LLC |