Volvo Penta Aquamatic 270T Workshop Manual (P/N 7724371-5, 7726380-4)

• An 86-page, two-PDF Volvo Penta factory set for Aquamatic 270B, 270C, 270D, and the 270T Power Trim installation: AQ270 Drive Workshop Manual P/N 7724371-5 (44 pages, English 06-1999) plus AQ270T Power Trim and Mounting Collar Workshop Manual P/N 7726380-4 (42 pages, English 05-1999).
• Covers outdrive removal and transom installation, upper, intermediate, and lower gear-housing repair, universal-joint service, propeller-shaft and vertical-shaft work, and final shift-control and retaining-pawl checks.
• Details gear shimming, backlash measurement, tooth-contact inspection, double-bearing-box setup, Silent-Shift cone-clutch service, and repair procedures for original and modified control mechanisms.
• Adds the 270T-specific hydraulic scope: Trim, Beach, and Tilt operation; symptom-based fault tracing; pump pressure and sealing tests; and hydraulic tank, valve-housing, and twin-valve repair.
• Includes hydraulic pump and liner service, lift- and trim-cylinder reconditioning, trim sender and cable replacement, trim-indicator adjustment, outdrive refitting, and post-repair functional checks.
• Provides hydraulic circuit drawings, electro-mechanical lift and 270T wiring diagrams, cross-sections, a fault matrix, exploded assembly drawings, special-tool part numbers, torque specifications, pressure-test data, approved fluids, capacities, and adjustment values.

How the Two Manuals Work Together

The 270T publication is a system supplement rather than a stand-alone gear-drive manual. Volvo Penta directs the technician to the AQ270B, 270C, and 270D workshop information for the drive itself, while the 270T book covers the special Power Trim equipment and mounting collar. Both PDFs preserve that factory split between mechanical drive repair and 270T hydraulic repair. The May and June 1999 dates identify these English publication issues, not drive model-year coverage.

AQ270 Gear and Drive Repair Coverage

The drive manual covers the upper gear housing, input drive and double bearing box, forward and reverse gears, universal joint, engaging sleeve, cone clutch, and shift-control mechanism. Shimming is supported by stamped housing and gear measurements, two setup methods, backlash checks, and tooth-contact pattern inspection. During upper-gear adjustment, the manual differentiates the 270B backlash range of 0.15-0.25 mm from the tighter 0.08-0.18 mm range used for 270C and 270D.

It also identifies the production change at PZ No. 272 1099, where the universal-joint center fastener changes from the earlier twelve-point bolt to a hex-socket screw with different tightening data. Separate repair instructions cover the later modified control mechanism. Standard and opposite propeller rotation are explained without requiring a gear-set change, an important point for twin installations.

Intermediate- and lower-drive sections address the steering yoke, retaining pawl, shift yoke, propeller bearing housing, propeller shaft, vertical drive shaft, oil-pump impeller, bearings, seals, and housing-to-housing shim setup. Further chapters cover anti-corrosion work, the standard electro-mechanical lift, and installation of the 1-inch and 4-inch drive extensions, P/N 814133 and P/N 814318.

270T Hydraulic Diagnosis and Reconditioning

The supplement maps hydraulic flow through trimming, lifting, lowering, Beach operation, obstacle kick-up, reverse lockout, and overload protection. Its fault-tracing matrix connects no-lift, hesitant-travel, position-drop, deceleration float-up, and reverse kick-up symptoms with electrical faults, a broken pump drive pin, a blocked transport vent, low oil level, valve leakage, and cylinder sealing problems.

Diagnostic coverage includes lift- and lowering-pressure checks, compressed-air valve isolation, hydraulic-tank sealing tests, and post-repair leak and function checks. Repair chapters cover the tank and valve housing, twin valves, pump piston and liner, relief and non-return valves, lift-cylinder piston, control valve, safety valves, protective bellows, trim cylinder, sender and cable, and trim-indicator adjustment.

The hydraulic specifications call for Type F automatic transmission fluid, with Dexron listed only when Type F is unavailable. Valve-opening pressures, fluid capacity, tip-up ranges, lifting time, component torque data, cable colors, wire sizes, and the 270T wiring diagram are included.

Diagrams, Tools, and Repair Cautions

Useful visual references include the Aquamatic 270 cross-section, the upper-gear tooth-contact pattern comparison, exploded mounting-collar and gear-housing drawings, the 270T hydraulic-system layout, the symptom-based fault matrix, and the 270T wiring diagram. Dedicated Volvo tools include upper-gear fixture 884387, pressure gauge 884418, lift-cylinder drift 884423, and hydraulic-piston tool 884424.

Upper-gear work is sensitive to parts order: matched needle bearings must not be mixed, forward and reverse gears must remain correctly identified, and reusable shim stacks must be tracked during teardown. On the hydraulic side, the pump liner must be indexed to the oil passages and lock pin without distortion; exposed lift-yoke threads can cut new cylinder seals, and sealant on the trim-cylinder O-rings or grooves can impair sealing.

Securely support the outdrive or lift yoke before pivot or cylinder work, and keep disconnected hydraulic lines plugged and clean. These procedures assume shop-level mechanical and electrical experience.