OMC Cobra, King Cobra & Stringer Sterndrive Manual Set (1964–1998)

The earlier manual explains the ball-gear and intermediate-housing arrangement. The later manual adds transom-mounted drive assemblies and electronic fuel-injection diagnosis, with separate procedures for the different drive configurations.

PDF Search, Bookmarks, and Wiring Detail

Finding procedures and reading diagrams: An OCR text layer supports text search, but coverage is incomplete on some specification tables, chapter-opening pages, and wiring sheets. Embedded bookmarks provide access to both manuals. Small wiring labels require enlargement, and some fine schematic lines are faint.

The download contains one printable, 1,183-page PDF. That total includes seven main contents pages, the earlier manual’s 97-page appendix, six master-index pages, and the one-page Engine Finder.

Engine Rebuilding and Sterndrive Service

The following selected coverage highlights the main repair areas. Additional topics include propeller selection and remote-control shift-box repair.

• Engine repair: Step-by-step engine removal and installation, cylinder-head reconditioning, piston-and-rod service, camshaft and crankshaft work, and valve-train adjustments.

• Sterndrive overhaul: Upper gear housings, lower gearcases, shift converters, intermediate housings, bearing inspection, gear shimming, and backlash adjustment.

• Fuel-system diagnosis: Rochester, Carter, and Holley carburetor repair, Ford electronic fuel injection, and GM TBI/MFI testing with diagnostic trouble-code charts.

• Ignition and electrical systems: Distributor servicing, electronic ignition checks, starter rebuilding, battery and alternator testing, and engine wiring schematics.

• Steering, trim, and tilt: Tru-Course and power steering, SelecTrim mechanisms, hydraulic pump and cylinder servicing, and electrical or hydraulic fault isolation.

• Cooling and seasonal care: Water-pump replacement, thermostat checks, exhaust-manifold servicing, zinc-anode inspection, corrosion control, and winter-storage preparation.

Boat owners can use the maintenance guidance, while detailed injection testing and drive rebuilding call for mechanical experience and suitable test equipment.

Engine Service and Internal Repair

The engine material distinguishes GMC in-line engines, Kaiser/GMC 225 and GMC 229 V6 configurations, and GM and Ford V8 engines. The later manual also treats the Ford overhead-cam four-cylinder engine and its timing belt.

Internal inspection extends to piston rings, connecting rods, main bearings, rear oil seals, and cylinder-head tightening sequences. Hydraulic valve-lifter adjustments, compression checks, spark-advance charts, and tune-up tables are matched to the applicable engine configuration.

Stringer, Cobra, and DuoProp Drive Work

Stringer coverage separates electric-shift units from the later power-assisted and mechanical-shift arrangements. It includes the 400/800-series units, shift converters, ball gears, swivel and exhaust housings, and intermediate-housing boots, supported by sectional illustrations.

The later manual distinguishes standard-rotation and counter-rotation Cobra/King Cobra procedures from SP/SX and DP work. These distinctions help you choose the appropriate lower-unit, shimming, and shift-system instructions before disassembly.

Transom servicing includes gimbal bearings, U-joints, and bellows. SP/SX and DP upper-housing procedures identify holding fixture 3850605 and retaining-ring spanner 3850604; a Drive Gear Backlash Table relates shim positions to gear clearance.

Gimbal-ring installation cautions explain how incorrect seating can damage the bearing.

Carburetors and Electronic Fuel Injection

Carburetor chapters cover Rochester BC, 2GC, and 4MV designs, Carter RBS units, and Holley carburetors. Illustrated bench work includes component inspection, reassembly, and adjustments.

Ford injection diagnosis provides pressure and leakdown checks, injector testing, and KOEO/KOER self-tests using equipment such as OMC MFI Tester 500004. GM coverage adds diagnostic-link checks, sensor tests, and fault-code charts for TBI and MFI systems.

Fuel-pressure-regulator section views and MAP-sensor schematics accompany the diagnostic material. ECM handling precautions identify static discharge at the connector pins as a potential cause of module damage.

Ignition, Charging, and Wiring References

Earlier distributor procedures distinguish Delco-Remy, Mallory, and Autolite/Prestolite equipment. Later chapters address EST, BID, Spitfire/EMM, and Ford TFI-IV ignition systems. Starter rebuilding covers Delco-Remy, Autolite, and Prestolite units.

Wiring references include SelecTrim wire-identification drawings and Ford-engine schematics showing shift-assist circuits, charging connections, and instrument senders. Battery and alternator testing accompanies the electrical troubleshooting material.

Cooling, Steering, and Trim Service

Cooling coverage distinguishes raw-water and closed systems, including drive-mounted impellers and engine-mounted supply pumps. Related work covers circulating pumps, thermostats, exhaust manifolds, system testing, and seasonal draining.

Steering and tilt: Tru-Course, mechanical steering, and power-assist systems have separate service material. SelecTrim hydraulics and later power trim/tilt assemblies are covered alongside the older hammer blow coupling, tilt clutch, and worm gear.

Trim-pump repair limit: For the 1986–88 Cobra/King Cobra system, the hydraulic pump is serviced as an assembly, although the surrounding pump assembly and valve-body components have disassembly procedures.

Follow the manual’s precautions for fuel vapor, electrical isolation, and lifting engine or drive assemblies, and use qualified marine help for work beyond your training.

A Preview of Injection Pressure Specifications

For the GM 1994–96 no-start diagnostic checks, fuel pressure with the ignition on and the fuel pump running is listed at 9–13 psi for TBI engines and 36–42 psi for MFI engines. These ranges belong to that diagnostic procedure; later configurations have separate specifications.