My 1988 Morbark Eeger Beaver chipper (see photo top) is one of the most important pieces of equipment in my arbor business: the removal and disposal of tree-trimming waste is a cornerstone of the service I provide. In September, 2011, the bronze sliding sleeve bearing on the PTO clutch disintegrated. Suddenly, I was without the chipper. After several months of attempting to acquire a replacement part, I finally discovered that the part in question was no longer manufactured. With the tree-trimming debris piling up, I decided to manufacture the part myself. This is what we did…
Specs:
1988 Morbark Eeger Beaver chipper. Engine: 4 cylinder cummins diesel
Step 1. A precise measurement of the cast iron sliding sleeve to which I was fitting the new bearing parts with a resultant schematic of all components (see photo 1).
Step 2. I placed an order with Chon at Tampa Steel & Pipe to the four components I needed to build the new part, assuming, correctly, that a steel shop equipped with a plasma cutter or a water-jet cutter would be better able to produce the parts within the fine parameters necessary for building a bearing. The three layers are as follows: inner shoulder: 2 semi-circles 3/8” thick steel plate, 2 ears ¾”x¾“; center layer: 1 circle ½” thick steel plate, 2 ears ¾”x¾”; outer shoulder: 1 circle 3/8” thick steel plate, 2 ears ¾”x¾”.
Step 3. After testing the fit of the new parts on the sliding sleeve, I assembled them in three layers on the shop bench, clamped them to the drill press, and cut holes at the point where the two ends of the inner shoulder parts met at a seam, through all three layers, to admit a hardened (#8) steel bolt 1 ½’X3/16”, with a larger hole cut n the inner shoulders to allow the bolt heads to be counter-sunk for minimum profile. With all four bolts installed and tightened, a turned the unit on its side and cut a single hole aprox ¼” through the center layer & threaded it for a grease fitting (the grease fitting will be serviced from under the aluminum service plate on the PTO Clutch Cover, so location must be considered when locating the hole). Finally, I put the entire assembled unit on the bench grinder and reduced the material of the ears until I had one 1” long pin on each side of the bearing to fit into the receiver on the PTO Clutch handle (see photo 2).
Step 4. Before installation, I dismantled the bearing and put the 2 inner shoulder parts on the welding bench, where I welded the heads of the bolts securely into the countersink recesses. After reassembling the bearing on the sliding sleeve, I returned to the welding bench and welded the nut-ends of the bolts to prohibit loosening of the unit in service (see photo 3). Should I need to remove the unit in the future, I can grind the welds off the nut-ends and undo the nuts with a wrench .
Total cost of the unit (without labor, which I provided myself and for which I will therefore not charge myself): $325.00
Anyone needing technical support on the above should please feel free to e-mail me at jonathanschork@aol.com.
update 7th december: the replacement part is functioning perfectly, the grease fitting is easy to access through the service plate, and the chipper is back in service.
