This is the COMPLETE Official Service Repair Manual for the Mercury Mercruiser #6 Sterndrive Units R, MR, Alpha One, Alpha One SS. Production model years 1983 1984 1985 1986 1987 1988 1989 1990. It Covers complete tear down and rebuild, pictures and part diagrams, torque specs, maintenance, troubleshooting, etc. You name it and its in here. This Manual contains everything you will need to repair, maintain, rebuild, refurbish or restore your Mercury Mercruiser Marine Engines. All diagnostic and repair procedures are covered. The manual has detailed illustrations, diagrams, wiring schematics and specifications as well as step-by-step instructions. All pages are printable, so run off what you need and take it with you into the garage or workshop. These manuals are your number one source for repair and service information. They are specifically written for the do-it-yourselfer as well as the experienced mechanic. Using this repair manual is an inexpensive way to keep your Mercury Mercruiser Marine Engines working properly. Each manual provides step-by-step instructions based on the complete disassembly of the machine. It is this level of detail, along with hundreds of photos and illustrations, that guide the reader through each service and repair procedure. MODELS COVERED: ======== TRANSOM ASSEMBLIES Model ----- Serial Number - MC 120R / 140B / 185R / 488R / 898R / 228R / 260R ----- 6216687 - 6849289 - MC 120MR / 140MR / 170MR / 185MR / 190MR / 200MR / 230MR / 260MR / 300 Tempest MR ----- 6849290 - 0A471374 - MC Alpha One / Alpha One SS ----- 0A471375 and Above STERNDRIVE UNITS MC 120R-260R Original Ratio ----- Ratio If Serviced With 13:21 Gears ----- Serial Number - 1.98:1 - 1.94:1 - 6237861-6854392 - 1.84:1 - 1.81:1 - 6225577-6862701 - 1.65:1 - 1.62:1 - 6268065-6810537 - 1.50:1 - 1.47:1 - 6229158-6847029 - 1.32:1 - 1.29:1 - 6231571-6663947 MC 120 MR - 300 TEMPEST MR Original Ratio ----- Ratio If Serviced With 13:28 Gears ----- Serial Number - 1.98:1 - 1.94:1 - 6854393-0A476746 - 1.84:1 - 1.81:1 - 6862702-0A470164 - 1.65:1 - 1.62:1 - 6810538-0A475786 - 1.50:1 - 1.47:1 - 6847030-0A479506 MC ALPHA ONE / ALPHA ONE SS Original Ratio ----- Ratio If Serviced With 13:28 Gears ----- R.H. Serial Number ----- L.H. Serial Number - 1.98:1 - 1.98:1 - 0A476747 and Above - 0C881740 and Above - 1.84:1 - 1.84:1 - 0A470165 and Above - 0C884040 and Above - 1.65:1 - 1.65:1 - 0A475787 and Above - 0C881790 and Above - 1.50:1 - 1.50:1 - 0A479507 and Above - 0C852908 and Above - 1.32:1 - 1.32:1 - 0A613927 and Above - Alpha One SS 1.50:1 / 1.32:1 - 1.50 / 1.32:1 - 0A545004 and Above SEA RAY STERNDRIVE UNITS AND TRANSOM ASSEMBLY (OYSTER WHITE) Original Ratio ----- Ratio If Serviced With 13:21 Gears ----- Serial Number - 1.98:1 - 0B803866-0C348031 - 1.84:1 - 0B800854-0C343526 - 1.50:1 - 0B796473-0C340666 - 1.32:1 - 0B804807-0C340030 - Transom Assembly - 0B815811-0C340333 When making repairs to Sea Ray (Oyster White) sterndrives, follow procedures as outlined for corresponding MerCruiser models as shown in the cross-reference chart below. SEA RAY ----- MERCRUISER - 3.0L - 3.0L Alpha One - 4.3L2 - 4.3L Alpha One - 4.3L4 - 4.3LX Alpha One - 5.7L - 5.7L Alpha One - SRX 5.7L - 350 Magnum Alpha One - SRX 7.4L - 454 Magnum Alpha One ______________________________ TABLE OF CONTENTS: ======== 1 - IMPORTANT INFORMATION A - Important Information B - Maintenance C - Troubleshooting 2 - REMOVAL, INSTALLATION AND ADJUSTMENTS A - All Models 3 - STERN DRIVE UNIT A - Drive Shaft Housing B - Gear Housing - MR / Alpha One / Alpha One SS C - Gear Housing - I-R D - Gear Housing - Alpha One Counter Rotation 4 - TRANSOM ASSEMBLY A - Service Procedures Requiring Minor Disassembly B - Service Procedures Requiring Major Disassembly 5 - POWER TRIM A - Oildyne Power Trim Pump (Plastic Reservoir) B - Oildyne Power Trim Pump (Aluminum Reservoir) C - Prestolite Power Trim Pump D - Trim Cylinders E - Dual Power Trim Control F - Auto Trim II 6 - STEERING SYSTEMS A - Power Steering B - Manual Steering 7 - CORROSION PROTECTION A - All Models ______________________________ ** Model Specification: Mercury Mercruiser #6 Sterndrive Units R, MR, Alpha One, Alpha One SS ** Model Year: 1983-1990 ** Language: English ** Total Pages: 566 ** File Format: PDF ** Requirements: Adobe PDF Reader ** ZOOM IN/OUT: YES ** INSTANT DELIVERY: YES ** Specifications: FULLY PRINTABLE & BOOKMARKED ** Compatible: All Versions of Windows & Mac, APP ISO, Iphone, Ipod, Android etc =========== This QUALITY manual is 100 percents COMPLETE and INTACT, no MISSING/CORRUPT pages/sections to freak you out! This PDF file is Bookmarked and SEARCHABLE to make what you need easy to find. Detailed illustrations, exploded diagrams, drawings and photos guide you through every service repair procedure. This manual can be viewed on any computer, as well as zoomed and printed. Complete download comes in PDF format which can work under all PC based Windows operating system and Mac also. It saves to your hard-drive and can be burned to CD-ROM. INSTANT DOWNLOAD MEANS THERE WILL BE NO SHIPPING COSTS OR WAITING FOR A PAPER OR CD MANUAL TO ARRIVE IN THE MAIL. YOU WILL RECEIVE THIS MANUAL TODAY VIA INSTANT DOWNLOAD ON COMPLETION OF PAYMENT VIA OUR SECURE PAYMENT PROCESSOR. WE ACCEPT ALL MAJOR CREDIT/DEBIT CARDS AND PAYPAL. YOU CAN DO THE REPAIRS YOURSELF AND SAVE MONEY $$ BUY FROM US AND I GUARANTEE YOU'LL BE A SATISFIED CUSTOMER AND CONTACT US IF YOU HAVE ANY QUESTIONS. Looking for some other Service Repair Manual, please check: