Bercomax Deluxe 2-‐stage Snowblower mounted on 1977

Transcription

Bercomax Deluxe 2-‐stage Snowblower mounted on 1977
Bercomax Deluxe 2-­‐stage Snowblower mounted on 1977 CASE 446 tractor April 2011 The project is complete. Here are my DIY instructions Tools -­‐ Drill and 3/8" and 7/16" bits (and a small 3/16" pilot bit if you like) box wrenches and or socket set hex wrenches 1/2" coarse (13tpi) threading die and handle A metal bending brake or vise for bending metal (I recommend you have someone do this for you with the right tools and knowledge) Angle grinder with cutting wheel Patience Materials -­‐ Original Bercomac 700227 Subframe for Ingersoll 3xxx/4xxx 3/8 and 7/16 bolts, washers and locknuts in varying lengths -­‐ grade 8 Two 1/2" i.d. x 3/4" o.d. x 1/2" long bushings 6" 1/2 inch threaded rod (coarse or 13 tpi) 1/2" threaded rod coupler 1/2" i.d. shaft collar blue loctite 7 inches of 1-­‐1/4" by 3/16" flat bar steel -­‐ rolled edge steel is nice if you can get it. There are three modifications necessary. NOTE: In all photos the view is from the seated position on the tractor unless otherwise indicated. Left or right means the drivers left or right when seated #1. Lengthen the spring tensioning rod. a. remove the rod from the hinge by removing the tension pin b. thread the end of the rod using a 1/2" coarse die (removing the powder coating will make this easier) c. apply loctite to the inside of the rod coupler and screw onto the newly threaded rod d. screw 6" of 1/2 threaded rod into the rod coupler and tighten -­‐ the loctite does the rest e. mount the shaft collar about 3/4" from the end of the threaded rod and tighten the set screw f. remount the entire assembly in the hinge and re-­‐install the tension pin #2. Mount the spring tensioned flat pulley on the left side of the subframe a. on the left side of the subframe, drill a 7/16" hole near the top. See photo for distance from existing holes. b. mount the flat pulley to the arm using the original hardware. Use the original spacer and washers to create a 'notch' on the left side of the pulley where the spring will be attached. c. mount the arm to the frame using two 1/2" i.d. x 3/4" o.d. x 1/2" long bushings and the original hairpin cotter key d. You may have to notch the Tractor Mount with the grinder to create clearance for the outer bushing. #3. Mount the static V pulley on the right side of the subframe a. fabricate the mounting bracket or have one made -­‐ see photos for dimensions -­‐ note that the holes on the long end of the bracket are 2-­‐3/4" on center
b. bolt the top end of the bracket to the subframe with a 7/16" bolt c. bolt the V pulley to the bracket with a 3/8" bolt. Use washers/shims between the pulley and bracket to get the correct clearance for the top bolt. d. determine where to drill the subframe to attach the bottom of the bracket. This requires a little trial and error as you have to make sure the two pulleys do not scrape and you have to leave room between the V pulley and the subframe in order to install the belt. Once you have the location marked drill a 3/8" hole and bolt the bracket to the frame. Here are the before and after pictures taken from about the same angle. Sorry, but the after image is a little fuzzy due to poor lighting. Someone asked if the bushings won't wear and make the idler arm mounting hole "sloppy?" I do not think so... The idler arm barely moves during operation, so there should not be a lot of friction to wear anything down. Also, all of the pressure on the idler arm is front to back, not side to side, which is what would tend to ream the hole out. Yearly inspection and cleaning before putting away should expose any possible issues here. If a problem DOES develop, the solution is to bore out the hole and weld in a section of tube like the original idler arm mount(s) on the right side of the subframe. (The intent is to not have to weld...) For those interested, you can download the original photos in higher resolution, and the drawing I gave to the metal stamping shop, from here -­‐-­‐> http://wap.omiss.net/berco.zip BEFORE AFTER ADDENDUM July 2013 I have since made a modification that I should share. I was always concerned whether or not the movement of the relocated idler pulley would eventually ream out the hole in the mule bracket and make it sloppy. This good news it that after two seasons of operation it did not wear at all. The other news is that the bushings themselves were wearing out rather rapidly and things were getting sloppy on account of that. I could have simply replaced the bushings, but having recently learned to weld I opted for the more permanent fix. I removed the idler arm assembly and the bushings and drilled out the hole to 5/8". Then I welded a section of ½”i.d. x 5/8”o.d. steel tube in place. Here are the before an after photos with and without those bushings.