Detroit Diesel 12V71 Turbo – Complete Engine Overhaul Kit Catalog

The Detroit Diesel 12V71 Turbo engine is one of the most powerful and widely used engines in the 71 Series lineup. Known for its durability, reliability, and performance, the turbocharged version provided higher horsepower and torque while retaining the proven two-stroke design Detroit Diesel was known for. To keep these engines running at their peak, a proper rebuild or overhaul is often necessary—especially for marine, industrial, and power generation applications where continuous duty demands can wear components down over time.

This catalog provides a comprehensive guide to overhaul kits, gaskets, seals, cylinder components, cooling system parts, and essential service tools for the Detroit Diesel 12V71 Turbo. Each section below has been carefully expanded to provide the depth of information needed for professionals planning or performing a rebuild.

Overview of the Detroit Diesel 12V71 Turbo

• Engine Type: Two-stroke, V-12 diesel engine

• Configuration: 12 cylinders in a 71 Series layout, turbocharged with intercooler or aftercooler options

• Displacement: 852 cubic inches (14.0 liters)

• Applications: Marine propulsion, auxiliary power, industrial equipment, stationary power generation

• Performance Benefits: Increased horsepower compared to natural aspiration, improved airflow from turbocharging, stronger cooling efficiency with aftercooler or intercooler options

The turbocharged and intercooled/aftercooled 12V71 was commonly installed in commercial vessels, offshore platforms, and heavy industrial equipment requiring continuous duty cycles. Because of these demanding environments, complete in-frame and major overhauls are essential to maintain reliability.

In-Frame Overhaul Kits for Detroit Diesel 12V71 Turbo

Turbo Intercooled Overhaul Kit

The in-frame overhaul kit for turbo-intercooled 12V71 engines contains all major wear components required to restore compression, efficiency, and fuel economy. It typically includes:

• Pistons and piston rings

• Cylinder liners

• Connecting rod bearings

• Main bearings

• Gasket sets

This kit is specifically designed for engines equipped with intercoolers, ensuring correct tolerances for the higher boost pressures produced by the turbo system.

Turbo Aftercooled Overhaul Kit

For engines equipped with an aftercooler, this rebuild kit includes similar core components but with slight specification differences to accommodate cooling characteristics and combustion performance unique to aftercooled models.

Choosing the correct kit—intercooled or aftercooled—is critical for long-term performance. Using the wrong configuration could result in improper compression ratios and cooling inefficiencies.

Cylinder Components and Related Service Tools

Cylinder Liner Puller

Removing cylinder liners from a 12V71 block requires specialized equipment. The liner puller tool provides a secure grip to extract liners without damaging the block, an essential step in an in-frame rebuild.

Liner Inserts and Shims

• Standard liner inserts maintain correct liner seating inside the block.

• Oversize liner inserts are available for blocks that have been machined to accept liners beyond standard tolerance.

• Liner shims (e.g., 0.002 thickness) are used to adjust liner protrusion height, ensuring consistent compression and preventing head gasket failures.

Gasket Kits for Complete Engine Coverage

Full Overhaul Gasket Kit

The 12V71 overhaul gasket kit provides all major gaskets required for a complete rebuild, including:

• Cylinder head gaskets

• Intake and exhaust manifold gaskets

• Oil pan gaskets

• Valve cover gaskets

• Seals for ancillary components

A full kit ensures that all sealing surfaces are properly restored, eliminating the risk of compression or fluid leaks after a rebuild.

Inspection Cover and Block Gaskets

For maintenance or partial disassembly, inspection gaskets allow mechanics to reseal access covers without replacing the entire gasket set. These are particularly useful during mid-life inspections when only certain components are removed.

Crankshaft Seals and Sleeves

One of the most common wear points in the 71 Series engines is the crankshaft seal. Oil leaks at the front or rear can compromise lubrication and create contamination risks.

• Front Seals (Standard & Oversize): Designed for universal rotation (LH or RH), compatible with turbocharged configurations.

• Rear Seals (Single Lip & Double Lip): Offered in both standard and oversize versions to fit engines that have seen extensive service.

• Seal Sleeves: Oversize sleeves are available when crankshaft surfaces are worn or damaged, providing a new sealing surface without requiring full crankshaft replacement.

Tune-Up Kits and Service Tools

Complete Tune-Up Kit

The tune-up kit for Series 53, 71, and 92 engines includes essential tools and calibration equipment for adjusting injectors, valves, and timing. Proper tune-ups are critical for the two-stroke design to ensure fuel efficiency and smooth operation.

Piston Ring Tools

• Piston ring compressors make installation of piston rings into cylinder liners safe and efficient.

• Piston ring assembly tools are required to correctly install rings without risking breakage or improper seating.

Using the right tools prevents costly mistakes during overhaul.

Oil Filtration and Lubrication Components

Oil Filters

Both spin-on filters and cartridge filters are available for Detroit Diesel 12V71 engines. Proper filtration is crucial to remove contaminants and protect bearings, pistons, and liners from accelerated wear.

Oil Filter Wrench

A specialized removal wrench accommodates the larger filters used in Detroit Diesel and Cummins engines, providing a secure grip without risk of damage.

Cooling System Components

Thermostats

The Detroit Diesel 12V71 Turbo requires precise cooling system regulation to handle turbocharged combustion temperatures. Available thermostat ratings include:

• 160 degrees

• 170 degrees

• 180 degrees

Each thermostat is designed for different operating conditions, allowing operators to tailor engine performance to ambient environment and duty cycle.

Thermostat Seals

Correct sealing prevents coolant leaks around thermostat housings, ensuring consistent temperature regulation.

Radiator Cleaner

Cooling systems in marine and industrial environments often face scaling and debris build-up. Radiator cleaner helps restore full cooling efficiency and prevent overheating.

Block Heater

For cold environments, a block heater ensures reliable starts by maintaining coolant and engine block temperature at optimal levels before ignition.

Electrical and Monitoring Components

Temperature Switches

Temperature switches automatically trigger alarms or shutdowns if coolant exceeds safe limits, protecting the engine from catastrophic overheating.

Gauges

• Mechanical gauges provide direct pressure and temperature readings.

• Electrical gauges are available in 12V and 24V configurations with or without alarms.

Accurate monitoring is critical for detecting early warning signs of wear or malfunction.

Paints and Primers

After a rebuild, applying Detroit Diesel green paint and primer not only restores OEM appearance but also protects against corrosion in marine and industrial environments.

Why Choose Diesel Pro Power for 12V71 Turbo Overhaul Kits

• Global Reach: Orders ship within 24 hours to over 180 countries.

• Proven Trust: More than 40,000 satisfied customers worldwide rely on Diesel Pro Power.

• Comprehensive Catalog: Everything from in-frame kits to service tools and gaskets in one place.

• Expert Guidance: Support team assists with selecting correct kits for turbo-intercooled or turbo-aftercooled engines.

• Marine & Industrial Specialization: Unlike general suppliers, Diesel Pro Power focuses on continuous-duty engines in demanding environments.