1/5 PURPOSE To install new top weight plate bushings in G7 strength units. RE-WORK PARTS REQUIRED - ZMS4000424 Top Weight Plate Bushing (Quantity 4 per machine). - Matrix Top Weight Plate Bushing Removal Tool - available upon request from THE TECH MUST RETURN THE PART ONCE THE REPAIR IS COMPLETE! - 12 (or larger) C Clamp / Bar Clamp - available at most hardware stores. PROCEDURE 1. Remove the 4 bolts holding the top cover onto the weight stack (Figure A). 2. Pull up on the top cover (Figure B) and disconnect the repetition counter wire from the top cover (Figure C) and remove the cover from the unit. Figure A Figure B Figure C 3. Remove the 3 weight stack shields by pulling them up and off the weight stack frame (Figures D-F). Figure D Figure E Figure F
2/5 4) Remove the 4 screws holding the clear plastic cover onto the top weight plate and remove it (Figures G-I). Figure G Figure H Figure I 5) Lift up the rubber cover where the cable meets the top weight plate (Figure J). 6) Turn the cable retainer counter clockwise to loosen it (Figure K). Once the cable retainer has been rotated a few times, the cable should be loose enough to remove from the cable retainer (Figure L). Figure J Figure K Figure L 7) Remove the top guide rod retaining clip on the 2 rear (head plate / add on weight) guide rods (Figure M). This will allow the guide rods to drop down into the frame. 8) Remove the bottom guide rod retaining clip on the 2 (head plate / add on weight) guide rods (Figure N). Figure M Figure N
3/5 9) Loosen the screw holding the guide rod stop to the guide rod (if applicable) and slide the guide rod stop off the guide rod (Figures O & P). NOTE: Not all models will have guide rod stops installed. 10) Lean the guide rods away from the unit. This will give you enough room to lift up on the top weight plate and remove it from the machine (Figure Q). Figure O Figure P Figure Q 11) Remove the 4 screws holding the increment weight adjustment plate to the top weight plate (Figure R), and remove the increment weight adjustment plate assembly (Figures S & T). Figure R Figure S Figure T 12) Use a file to remove the sharp point on the set screw that adjusts the increment weight (Figure U). 13) Use a file to round the edges on the ridges that the set screw slides on (Figure V). Steps 12 & 13 are designed to prevent a groove forming on the ridges as shown in Figure W. Figure U Figure V Figure W
4/5 14) Remove the C-clip holding the increment weight pin to the top weight plate (Figure X) and remove the pin. 15) Use a file to remove any ridges preventing the increment weight washer from sitting flush against the top weight plate (Figure Y). This should tighten the increment weight pin to the top weight plate and should resolve any issues with increment weight pin looseness. Figure X Figure Y 16) Re-install the increment weight adjustment plate assembly and the increment weight pin to the top weight plate. 17) Use the Matrix Top Weight Plate Bushing Removal Tool to remove the 4 bushings in the top weight plate (Figures Z, AA, & BB). If the TWPB Removal Tool is not available, it is possible to remove the bushings by first cutting the bushings with a razor and then forcing them out with a small flat bladed screwdriver. Figure Z Figure AA Figure BB
5/5 18) Each new bushing has one end that is rounded (Figure CC), this end should go into the top weight plate first. Use a 12 (or larger) C Clamp / Bar Clamp (available at most hardware stores) to press in 4 new bushings into the top weight plate one at a time (Figure DD). Rounded Edge Figure CC Figure DD 19) Re-install the top weight plate and re-attach the guide rods to the unit. 20) Use Super Lube Multi Purpose to thoroughly lubricate the guide rods. Move the top weight plate up and down the guide rods several times so that lubrication works its way onto the bushings. 21) Reverse Steps 1-9 to re-assemble the unit. 22) Test the unit for function including sliding the weight stack pin in and out at various places on the stack.