New Lower Unit Gearcase Seal Kit Compatible With 1990-1993 Omc Cobra 3.0L 4-Cylinder Sterndrive

OMC COBRA STERNDRIVE LOWER UNIT GEARCASE SEAL KIT — Comprehensive Service Kit (1986-1993):

STERNDRIVE PLATFORM CONTEXT:
• OMC Cobra is a STERNDRIVE (Drive Unit), NOT an Outboard
• Reference #45 on OMC Cobra Lower Gear Housing Chart
• Production Years: 1986-1993 (V6/V8) / 1990-1993 (3.0L 4-Cyl)
• Replaced by OMC SX Sterndrive in 1994
• Distinct from OMC Stringer (Older Drive) and OMC King Cobra (Higher-Power Variant)

OMC COBRA V6 / V8 STERNDRIVE APPLICATIONS (1986-1993):
• OMC Cobra V6 4.3L Sterndrive (1986-1993)
• OMC Cobra V8 5.0L Sterndrive (1986-1993)
• OMC Cobra V8 5.7L Sterndrive (1986-1993)
• OMC Cobra V8 5.8L Sterndrive (1986-1993)

OMC COBRA 3.0L 4-CYLINDER STERNDRIVE APPLICATIONS (1990-1993):
• OMC Cobra 3.0L 4-Cylinder Sterndrive (1990-1993)
• Original 4-Cylinder Cobra Platform

PAIRED ENGINE COMPATIBILITY (Drive Fits — Not Specific to Engine HP):
• 3.0L Inline 4-Cyl (135-140 HP) Paired with OMC Cobra 1990-1993
• 4.3L V6 (175-205 HP) Paired with OMC Cobra V6 1986-1993
• 5.0L V8 (215-225 HP) Paired with OMC Cobra V8 1986-1993
• 5.7L V8 (260-280 HP) Paired with OMC Cobra V8 1986-1993
• 5.8L V8 (285-310 HP) Paired with OMC Cobra V8 1986-1993
• HP Rating of Paired Engine Does NOT Determine Fitment

⚠️ NOT COMPATIBLE WITH:
• OMC Stringer Sterndrive (Older Drive — Different Platform)
• OMC King Cobra Sterndrive (Higher-Power Variant — Different Kit)
• OMC SX Sterndrive (Newer Drive 1994 & up — Different Kit)
• OMC SX-M Sterndrive (Single Prop — Different Kit)
• OMC SX-DP / DP-S Sterndrive (Dual Prop — Different Kit)
• OMC 400 / 800 Sterndrive (Older Pre-Cobra Drive)
• OMC Cobra 2.3L 4-Cyl (1987-1990) — Different Earlier Cobra Variant
• OMC Cobra 2.5L 4-Cyl (1986) — Different Earlier Cobra Variant
• OMC Inboard Applications (Direct Drive — No Sterndrive)
• MerCruiser / Volvo Penta / Yamaha Sterndrives (Different Brands)

SPECIFICATIONS:
• Type: Lower Unit Gearcase Seal Kit (Comprehensive)
• Application: OMC Cobra Sterndrive Outdrives
• Drive Type: Sterndrive (NOT Outboard — NOT Stringer)
• V6/V8 Coverage: 1986-1993
• 3.0L 4-Cyl Coverage: 1990-1993
• Includes: Oil Seals, Gaskets, O-Rings, Drain Plug Gaskets
• Material: Marine-Grade Rubber Compounds (Saltwater + Heat Resistant)
• Function: Complete Lower Unit Seal Replacement
• Condition: New
• Reference: #45 on OMC Cobra Lower Gear Housing Chart

OEM PART NUMBERS:
• OMC: 439967 / 0439967 (Primary OEM)
• OMC: 984458 / 0984458 (OEM Cross-Reference)
• OMC: 984965 / 0984965 (OEM Cross-Reference)
• OMC: 985613 / 0985613 (OEM Cross-Reference)
• OMC: 987548 / 0987548 (OEM Cross-Reference)

KIT CONTENTS:
• Oil Seals (Multiple Positions)
• Gaskets (Various Sizes)
• O-Rings (Multiple Positions)
• Drain Plug Gaskets

WHEN TO USE THIS KIT:
• Lower Unit Complete Rebuild
• Annual Lower Unit Service Interval
• Water in Gear Oil (White / Milky Appearance)
• Gear Oil Leaking from Prop Shaft Area
• Gear Oil Leaking from Drive Shaft Area
• Replacing Forward / Reverse Gear Thrust Bearings
• Replacing Prop Shaft Bearings
• Drive Shaft Service
• Routine Preventive Maintenance for OMC Cobra Sterndrive

SYMPTOMS REQUIRING SEAL KIT REPLACEMENT:
• Milky / White Gear Oil at Service Drain (Water Contamination)
• Gear Oil Leaking from Prop Shaft Area
• Gear Oil Leaking from Drive Shaft Area
• Failed Pressure Test During Routine Service
• Lower Unit Running Hot
• Cloudy / Discolored Gear Oil
• Loss of Lubrication
• Routine Annual Service Interval Reached

INSTALLATION:
• Step 1: Drain old gear oil completely (note color / condition)
• Step 2: Remove sterndrive from boat transom assembly
• Step 3: Take photos and notes of disassembly order / orientation
• Step 4: Disassemble lower gearcase per OMC Cobra service manual
• Step 5: Remove all old seals, gaskets, o-rings using proper seal tools
• Step 6: Clean all sealing surfaces thoroughly
• Step 7: Inspect gearcase housing for damage or corrosion
• Step 8: Install new seals with proper orientation (lip direction critical)
• Step 9: Install new gaskets and o-rings with light marine grease
• Step 10: Reassemble gearcase per OMC Cobra service manual torque specs
• Step 11: Pressure test gearcase before reinstalling sterndrive
• Step 12: Reinstall sterndrive to transom assembly
• Step 13: Refill with proper OMC HI-VIS Premium Blend Gearcase Lube
• Step 14: Test forward and reverse operation

⚠️ IMPORTANT — VERIFY DRIVE TYPE:
• Look at the drive unit and identify "Cobra" stamp / label
• Cobra has distinctive shaped lower unit housing
• Cobra produced 1986-1993 (replaced by SX in 1994)
• King Cobra is a separate higher-power variant — uses different kit
• Stringer is the older OMC sterndrive — uses different kit
• SX / SX-M / DP-S are newer drives — use different kits

NOTE: Verify your OEM part number 439967 / 984458 / 984965 / 985613 / 987548 AND your drive type before ordering. ***This kit fits ONLY OMC Cobra sterndrive V6/V8 (1986-1993) and 3.0L 4-Cyl (1990-1993).*** Does NOT fit Stringer (older drive), King Cobra (higher-power variant), SX/SX-M/DP-S (newer drives 1994+), or earlier Cobra 2.3L/2.5L variants. ***Note: OMC Cobra is a STERNDRIVE — kit fits the drive itself, not specific to any engine HP rating.*** Replace all seals concurrently for proper lower unit longevity.