Perkins 4.108M, 4.107M, & 4.99M 1980–1981 Parts Manual (P/N NAP000265)

• 106-page PDF for the Perkins 4.108M North America Version, identified on the cover as NAP000265 PB, Issue 1 and indexed to Build List NAP000265. The individual catalog sheets carry dates from August 1980 through November 1981, with revised illustration sheets marked Issues 1, 2, and 3.
• Forty-seven indexed component breakdowns organize the engine into core sections, option packs, accessories, and gasket sets. Each parts page ties illustration references to Perkins part numbers, quantities, descriptions, assembly-inclusion notes, and non-serviced-item information.
• Core engine coverage spans the cylinder block; crankshaft, pistons, and connecting rods; cylinder head; rocker shaft; timing gear and camshaft; and the lubricating-oil pump and delivery housing.
• Marine fuel, cooling, and air-system plates cover diesel injection equipment, three low-pressure fuel-system arrangements, the fuel pre-lift pump, cold-start equipment, water pump/header tank/heat exchanger configurations, the gear-driven sea-water pump, induction manifold, air cleaner, exhaust manifold, and exhaust outlet flange.
• Drive, mounting, control, and electrical hardware includes PTO clutch and gearbox arrangements, flywheel housing, flywheel and starter ring, front-end drive input and output, starter motor, alternator/generator mounting, engine lifting plates, front and rear mounts, throttle and stop controls, pressure and temperature senders, tachometer/hour-meter equipment, wiring harnesses, instrument panels, and safety-alarm switches.
• Configuration notes are tied to actual build and option references, including the electrical application break at engine 108U107098/108U107099, selected NAP000273 cross-references, and option-coded senders, controls, panels, harness lengths, PTO parts, and oil-system components.

Build-List Organization and Parts Identification

This is a Perkins Core & Option Parts Book, not a generic model-family catalog. Its own instructions direct the reader to begin with the build-list index, identify the applicable core, option, or accessory pack, and then move to the matching coded breakdown. That structure matters on a marine engine where two assemblies can look similar while using different brackets, hoses, senders, or service kits.

The opening index lays out all 47 subjects by pack code and plate number, while a separate numerical index helps locate a known part number. Entries are presented in English, French, and Spanish. On the parts pages, the reference number follows the drawing callout; additional columns show the Perkins number, quantity, and description. A cross-reference beside an item can mean that the component is contained in a larger assembly. Where an item is not serviced separately, the catalog directs the buyer to the complete assembly or repair kit rather than suggesting a guessed individual part.

Engine, Marine, and Accessory Breakdown Depth

The internal-engine plates go well beyond a single general engine view. Representative drawings include Crankshaft, Pistons, Connecting Rods, Timing Gear & Camshaft, and Lubricating Oil Filter and Integral Oil Cooler. Marine-specific coverage is equally clear in the Water Pump, Header Tank, Heat Exchanger, Gear Driven Sea Water Pump, and PTO Clutch & Gearbox plates. Separate pages distinguish alternate sump, cooler, control, sender, tachometer, and panel arrangements instead of merging them into one ambiguous illustration.

The catalog also identifies top and bottom service gasket sets and marks selected alternatives, repair kits, parts supplied by Delco, and components serviced in pairs. Its instructions further state that a part omitted from an illustration may be supplied by the equipment manufacturer or may not be required on the listed engine. That note is important during repair planning: an empty space on a drawing is not evidence that a similar-looking Perkins part belongs there.

Fitment Notes and Scope Limits

Use the engine identification plate and build-list number before ordering. The NAP000265 index contains a few comparison notes involving NAP000273, but those notes do not turn this into blanket NAP000273 coverage. The electrical application section also changes switch and option references at engine 108U107099, with separate option codes for harnesses and instrument panels. Crossing those identifiers can result in incompatible repair parts even when the basic 4.108M layout appears the same.

This publication is a parts-identification catalog. It does not contain removal and installation procedures, torque tables, clearances, test specifications, troubleshooting charts, calibration instructions, or electrical wiring schematics. A workshop manual is required for those repair procedures.

One scan limitation should be clear before purchase: the Alternator and Generator illustration appears twice in the PDF, and the corresponding parts-list page is not present. The other indexed sections retain the illustrated-plate and parts-list format.