On an aluminum boat tubes must be welded into the transom to accomodate the Vibra-Stop bushing kit. The Vibra-Stop bushing kit is the ultimate in vibration reduction when combined with either our 10MM-BP, MDRNG-BP, V6-BP or VRD-BP backing pads. The bushing kit mechanically isolates the engine mounting bolts from the transom by forming a flexible elastomeric mount between the boat and the outboard engine. This results in a much quieter boat. Extensive testing has proven that this kit reduces vibration in boats by up to 50% more than just backing pads alone.
Installation instructions for aluminum boats:
1. Using your usual outboard placement criteria cut the four mounting holes to 51 mm.
2. Insert one weld-in alloy tube at a time into a 51 mm hole and tack weld in place. Repeat for all four tubes. Take a straight edge to make sure that each tube is welded at exactly 90 degrees to the transom.
3. Insert the Vibra-Stop bushings into the transom with the stepped end of the bushing facing toward the front of the boat. Check that the bushing does not extend beyond the back side of the transom. If it does, use a sharp hacksaw to cut it so that it is flush or short of the back side of the transom. Hang your motor against the transom and check that your bolts holes all line up with the outboard bracket. After you are are satisfied with the alignment of the tubes, remove the bushings and finish welding the tubes in place. Reinstall the bushings with a polyurethane sealant.
4. Select four high tensile mounting bolts long enough to extend through the bushings, transom, Vibra-Stop pad, motor mount and leave sufficient thread to capture a nyloc nut.
5. Insert bolts through the stainless cup washers and the bushings, run some sealant around bolts outside back of transom. Hang the Vibra-Stop backing pads on the bolts on the back side of the transom. The sharp edge of the pad goes against the boat transom, the radius side of the pad faces backwards.
6. Hang the motor on the boat using the mounting bolts and secure with nyloc nuts. Torque the bolts to 30 ft lbs. Mercury Verado ONLY, torque to 38 ft lbs.
7. Once the engine is secure on the back of an aluminum boat you must bond the engine back to the boat using the Vibra-Stop bonding system p/n EW. Do this by drilling an 8 mm hole in the back of the transom below the outboard. Place the plastic stepped bushing through the hole from the inside of the transom. Put the bolt through the bushing and fit the aluminum washer supplied on the outside of the transom, ensure the metal is clean under the washer (no paint). Put the loop of the ground strap over the bolt and tighten it using a stainless steel washer and 6 mm nyloc nut. The other end of the ground strap must be placed under the bolt on the trim anode of the outboard engine.
8. Check the mounting bolt torque after 10 hours of operation and thereafter at least every 100 hours.
NOTE: If fitting any motor over 130HP be sure to install Anodized Aluminum Keys p/n AAK in the slots with the bottom bolts. Choose the keys that line up with the slot and the bolt. Before fitting the keys apply Vaseline or silicone grease to the keys to ensure salt does not build up in the slots.
NOTE: A jig plate is available to facilitate installation of tubes in transom. We require a $500 fully refundable deposit. There is no charge for using the jig other than shipping to you. Upon return of the undamaged jig to us the $500 deposit is fully refunded. email [email protected] if you wish to use our jig.
