Description

Porsche 928 1977 Workshop Manual

Missing torque specs on a head bolt job? Hammering a bolt you know should be tightened to spec but the aftermarket book shows a range? That’s the kind of frustration that wastes your Saturday and bends parts. Official factory documentation eliminates that guesswork. The Porsche 928 1977 Workshop Manual gives you the exact numbers Porsche wrote for their techs – not a reprint from some third-party publisher who never touched a 928.

This is the actual OEM manual printed for the Porsche dealer organization. 398 pages broken down by repair groups. You get everything from the air flow controlled fuel injection to the antiblock system. Every torque value, every clearance, every step – it’s all here because the factory wrote it for technicians who had to get it right the first time on customer cars.

Engine, Crankshaft, Pistons – Repair Group 13

Group 13 covers the engine block from the bottom end up. Crankshaft bearing clearances, piston ring gaps, and the cylinder head torque sequence. If you are rebuilding the 4.5L V8, you need these numbers. Aftermarket manuals often list one generic torque for head bolts – this manual gives stage torque and angles. Check page 3 for the full list of repair groups – 0.1 through 97. You will see exactly where each procedure lives.

What Torque Values Does This Manual List?

Page 4 shows a table of torque specifications for the manual transmission, clutch, central tube, and differential. The factory-specified torque for the clutch pressure plate bolts, the transmission-to-engine bolts, and the axle shaft nuts are all documented. No ranges, no “tighten to 80-100 Nm” – you get the precise number. That is the difference between a joint that holds and one that loosens after 500 miles. Make it a habit to check this page before any transmission or clutch job.

For engine fasteners, the manual covers the cylinder head, main bearing cap, connecting rod, and flywheel torque values. Each specification includes the tightening sequence. The 1977 928 uses a specific pattern for the cylinder head – skip it and you risk a warped deck or a blown head gasket. This manual shows the steps in the original factory wording, not a paraphrased version that lost the critical order.

Chassis and Brakes: Factory Procedures

Repair Groups 40 through 47 cover front and rear suspension, wheels, tires, alignment, brakes, and steering. The antiblock system (Group 45) is included – that is rare for a 1977 manual. If you are troubleshooting an early ABS system on a 928, the diagnostic flowcharts here are the only reliable source. The manual also gives the alignment specs: caster, camber, and toe-in for the 928. Without factory data, aligning a 928 to generic specs will chew through tires.

3 Critical Systems Covered in This Manual

1. Fuel Injection – Repair Group 24: Air flow controlled K-Jetronic system. Complete troubleshooting procedures, pressure tests, and adjustments for the warm-up regulator and cold start valve.
2. Automatic Transmission – Repair Group 37: Disassembly, gear and valve body specs, torque converter checking. The manual includes the procedure for setting clutch pack clearance.
3. Electrics – Repair Group 97: Wiring diagrams for the entire car: exterior lights, interior lights, wipers, radio, alarm system, and the fuel gauge. Color-coded wires with gauge sizes.

Understand the Wiring Before You Touch It

Electrical work on a 1977 928 can stall your project fast if you rely on a generic diagram. The factory wiring in this manual shows the exact routing and connectors used for that model year. The K-Jetronic injection harness is unique – one wrong splice and the engine runs lean. The manual’s Electrics section gives you the schematic for the air flow sensor, the fuel pump relay, and the ignition system. You also get the terminal numbers for the fuse box (Repair Group 94). This level of detail is why dealerships kept these manuals locked in the service office.

Porsche 928 1977 Workshop Manual – How It’s Organized

The manual is divided into Repair Groups, not chapters. Each group covers a specific system. For example, Group 28 is the exhaust system and emission controls. Group 34 is the starter, power supply, and cruise control. The table of contents on page 3 lists every group. If you need to jump to the rear axle, go to Group 42. No flipping through a generic index. The manual also includes technical data sections that list capacities, tolerances, and tightening torques for each group. The 1977 928 uses a specific transaxle design – the manual shows the torque tube and clutch linkage setup in detail.

Related manuals that complement this one include the Porsche 928 Workshop Manual for other model years and the Porsche 928 Workshop Manual – Section: Repair Groups if you want a quick reference. For transmission-specific work, the Porsche 911 Carrera 4 & Carrera 2 1995 Workshop Manual Vol 2 Transmission covers later Porsche gearbox procedures that share design principles. For background on Porsche engineering philosophy, see the Automotive Industry Overview and the article on Manual Transmission design.

One note about authenticity: This is an original Porsche publication, printed in Germany. It is not a scanned aftermarket copy with blurred diagrams. Every page is clear, and the torque specs are legible. Aftermarket manuals often have typos in critical numbers – I have seen a manual list 100 Nm for a bolt that should be 30 Nm. That will cost you a cracked housing. This manual carries the official Porsche part number WKD 481 621 and print number W 42-608-126-1. If someone offers you a “reprint” or a “compilation,” walk away.

Is this manual for the 1977 model year only?

Yes, it covers the 1977 Porsche 928 specifically. Many mechanical specs carry over to later years, but always verify against the correct year manual.

Does it include wiring diagrams?

The Electrics section (Repair Group 97) contains full wiring diagrams for the 1977 928. You get the factory layout for the fuse box, ignition system, fuel injection relay, and all exterior lights. Each wire is identified by color code and gauge. The manual also includes a diagnostic procedure for the alarm system (Group 96). This is the same documentation Porsche dealerships used. Without these diagrams, you are guessing which wire powers what – and that leads to shorts, blown fuses, or a no-start condition. The 1977 928 has a unique K-Jetronic injection harness; the diagram shows you exactly which wires go to the air flow sensor and the cold start valve. If you are restoring a 928 or chasing an electrical gremlin, this section alone is worth the price. Over 30 pages are dedicated to the electrical system, including the antenna and windshield wipers.

Can I use this for a 1980 928?

Some sections may apply, but the 1980 models had changes in the engine management and chassis. The 1977 manual is specific to that year. For later models, look for the corresponding year manual.

What about the automatic transmission?

The manual covers the automatic transmission in Repair Group 37. You get step-by-step disassembly, torque values for the valve body, and clutch pack clearance specs. It also includes the procedure for checking the torque converter. This is factory data, not a third-party rewrite. The manual has 398 pages, so every procedure has room for detail.

If you are working on a 1977 928, stop using aftermarket photocopies and access the real thing. Access the Factory Manual and get the same data Porsche issued to its technicians. No guessing, no aftermarket errors – just the original workshop manual that made the 928 serviceable by dealers.