This detailed rebuild guide will walk you through the process of using the Buckshot Racing #77 Repair Kit for the Mercury Outboard 2-Stroke V6 Power Trim Cylinder, replacing the more expensive Mercury Mariner OEM part number 79879A1 kit. Ensure you work in a clean, lint-free environment to prevent contamination of hydraulic components.
Tools Required:
Spanner wrench
Suitable container for draining oil
Non-toxic solvent
Compressed air
Loctite “271”
Torque wrench (58-72 ft. lbs.)
Disassembly Instructions:
Preparation:
Disconnect the hydraulic hoses from the power trim cylinder as described in the Mercury Outboard service manual.
Drain Hydraulic Oil:
With the trim cylinder removed, direct the up and down ports into a suitable container.
Push the trim rod in and out several times to drain the oil completely.
Remove Trim Rod Assembly:
Using a spanner wrench, unscrew the rod guide and pull the trim rod assembly out of the cylinder.
Extract Floating Piston:
Remove the floating piston by tapping the open end of the cylinder on a block of wood. Discard the old O-ring from the piston.
Disassemble Shock Piston:
Unscrew the bolt from the trim rod end.
Remove the large washer and shock piston assembly.
Extract the two O-rings, compression springs, spring guides, spring seats, and check balls. Discard the old O-rings.
Remove Rod Guide Components:
Take off the rod guide from the trim rod.
Remove and discard the retaining ring, plain washer, scraper, and three O-rings from the rod guide.
Clean All Components:
Use a non-toxic solvent to clean all parts thoroughly.
Dry each component with compressed air before reassembly.
Reassembly Instructions:
Prepare Rod Guide:
Lubricate all internal parts with SAE 10W-30 or 10W-40 motor oil.
Install three new O-rings (from the kit) onto the rod guide.
Install the new scraper, plain washer, and retaining ring.
Slide the rod guide over the end of the trim rod.
Rebuild Shock Piston:
Install the check balls, spring seats, compression springs, and spring guides into the shock piston.
Install two new O-rings from the kit onto the shock piston.
Assemble Trim Rod:
Place the shock piston and large washer onto the end of the trim rod.
Apply Loctite “271” to the piston rod bolt threads.
Tighten the bolt into the piston rod to a torque specification of 58-72 ft. lbs. (8.02-9.95 mkg).
Install Floating Piston:
Fit the new O-ring from the kit onto the floating piston.
Insert the piston into the cylinder with the blunt end first.
Final Assembly:
Insert the trim rod assembly into the trim cylinder.
Thread on the rod guide and tighten securely.
Post-Rebuild Steps:
Reconnect the hydraulic hoses.
Refill the hydraulic system with the manufacturer-recommended fluid.
Bleed the system to remove air pockets.
Test for smooth operation and check for leaks.
Mercury Long Ram Rebuild Instructions - Free PDF Download
Comments