Volvo Penta Aquamatic 270/270T Workshop Manual Set, 1999 (P/N 7724371-5)

Volvo Penta directs technicians to the AQ270 drive manual for mechanical work on the 270T drive. The supplement covers the 270T-specific hydraulic Power Trim system and mounting collar.

PDF Search, Diagrams, and Download

Search and diagram detail: The text in both PDFs is searchable. Each has a contents page, and neither has embedded PDF bookmarks. The wiring diagrams are legible at page size, with zoom making the smallest relay terminal numbers and wire codes easier to read.

The ZIP contains two printable PDFs totaling 86 pages, including both front and back covers, one blank page and one report form in each manual, and two notes pages in the 270T supplement.

Sterndrive Overhaul and Power Trim Diagnostics

These are selected workshop topics. The manuals also cover zinc anode inspection and cooling-water hose and bellows clamp positioning during drive refitting.

• Gear housing overhaul: Remove and refit the sterndrive at the transom, recondition the upper, intermediate, and lower housings, and service the universal joint and drive shafts.

• Gear setup and shift control: Set up the double bearing box, shim the gears, check backlash and tooth contact, and overhaul the original or modified shift-control mechanism.

• Power Trim fault tracing: Use the Trim, Beach, and Tilt circuit drawings, symptom chart, and lift and lowering pressure checks to diagnose hydraulic faults.

• Pump and cylinder repair: Recondition the hydraulic pump, valve housing, lift cylinder, and trim cylinder, with separate procedures for the trim sender, cable, and indicator adjustment.

• Lift and electrical references: Recondition the standard electromechanical lift and use separate wiring diagrams for that lift and the 270T hydraulic system.

Volvo Penta wrote these manuals primarily for its service workshops and qualified personnel with experience in marine drive systems and related mechanical and electrical work.

AQ270 Gears, Clutch, and Propeller Rotation

Upper gear setup: Two shimming methods cover the forward and reverse gears. The manual shows how to use stamped gear and housing measurements, check tooth-contact patterns, and apply the correct upper-gear backlash specification for the B, C, or D version. It also covers the Silent Shift cone clutch and its engaging sleeve.

Production changes: From PZ No. 272 1099 onward, the universal-joint center fastener changes from a twelve-point bolt to a hex-socket screw with its own torque specification. The later shift-control mechanism uses a neutral-position groove and has a separate overhaul procedure.

Lower drive and final checks: The manual covers the steering yoke, shift yoke, retaining pawl, propeller bearing housing, propeller shaft, vertical shaft, oil-pump impeller, seals, and shimming between housings. It explains how the shift linkage changes for standard and opposite propeller rotation with the same gear set, a distinction that matters on twin installations. It also covers final shift and retaining-pawl checks and fitting the 1-inch and 4-inch drive extensions, P/N 814133 and P/N 814318.

270T Hydraulic Tests and Reconditioning

Troubleshooting: The fault chart links hesitant travel, loss of position, float-up during deceleration, and kick-up in reverse to specific tests. If the drive will not lift, the checks help distinguish an electrical fault or broken pump drive pin from low oil, a blocked tank vent, or leakage past a valve or cylinder seal. The supplement shows hydraulic flow during raising, lowering, obstacle kick-up, reverse lockout, and Beach-mode overload.

Pump and valve housing: The supplement covers hydraulic tank sealing tests, compressed-air checks to isolate leaking valves, and reconditioning of the pump piston, liner, twin valves, relief valves, and non-return valves. Its fluid specification calls for Type F automatic transmission fluid and lists Type A or Dexron when Type F is unavailable.

Cylinders and refitting: The lift and trim cylinders can be removed with the drive in place. Lift-yoke removal requires taking the drive off. The supplement covers piston seals, the control and safety valves, protective bellows, sender and cable replacement, indicator adjustment, and leak and function checks after reassembly.

Drawings, Special Tools, and Assembly Cautions

The drawings include an Aquamatic 270 cross-section, upper-gear tooth-contact patterns, exploded mounting-collar and gear-housing views, and the 270T hydraulic layout. Both wiring diagrams include cable colors and wire sizes. The tool references identify upper-gear fixture 884387, hydraulic pressure gauge 884418, lift-cylinder drift 884423, and lift-cylinder piston tool 884424.

The gear procedures flag matched needle bearings, forward and reverse gear identification, and shim stacks that may be reused. The 270T procedures show why pump liner alignment matters, how exposed lift-yoke threads can damage seals, and where sealant can impair trim-cylinder O-ring sealing. They also show where the drive or lift yoke needs support and which hydraulic connections need protection from contamination.

Bearing Setup and Trim-Angle Examples

For the AQ270 input drive, the double bearing box procedure gives a spring-scale pull of 1.1–2.2 lb for new roller bearings and 0.9–1.6 lb for run-in bearings.

The 270T supplement gives a trim range of −4° to +4° with the standard trim plate and 0° to +8° with the oversize plate.