Parts for Detroit Diesel 371 Non-Turbo - (2 Valve Head Type) for Canada - Exhaust Section

Parts for Detroit Diesel 3-71 Non-Turbo – (2 Valve Head Type) – Exhaust Section

The Detroit Diesel 3-71 non-turbo engine is one of the most reliable members of the legendary Series 71 family, a line of two-stroke diesel engines that powered countless marine, industrial, and military applications for decades. Known for its compact design, dependable performance, and simple mechanical construction, the 3-71 remains a trusted workhorse among operators worldwide.

In any diesel engine—especially one used in continuous-duty or marine environments—the exhaust system is vital to performance, temperature control, and engine longevity. Proper maintenance of exhaust manifolds, gaskets, flanges, elbows, and mufflers ensures optimal power output and reduces the risk of leaks, backpressure, or overheating.

This expanded exhaust section from Diesel Pro Power highlights every major exhaust-related component available for the Detroit Diesel 3-71 Non-Turbo (2-Valve Head Type) engine. Each item listed below is backed by Diesel Pro Power’s quality guarantee and ready for fast worldwide shipping, with thousands of satisfied customers who trust Diesel Pro as their go-to source for Detroit Diesel replacement parts.

The Role of the Exhaust System in the Detroit Diesel 3-71 Engine

The exhaust system in the 3-71 engine not only directs hot gases safely out of the combustion chamber but also contributes to maintaining proper engine pressure and exhaust temperature. When this system is functioning efficiently, it prevents harmful exhaust leaks, maintains engine efficiency, and supports the water-cooled marine design that keeps the engine at an optimal operating temperature.

Key functions include:

• Heat dissipation: Preventing thermal stress on nearby components.
  
  

• Emission routing: Safely channeling exhaust gases out of the vessel or equipment.
  
  

• Backpressure control: Maintaining proper flow to avoid performance loss.
  
  

• Noise reduction: Especially critical in marine and industrial applications.
  
  

Every gasket, flange, elbow, and manifold plays a role in achieving these functions—each one forming part of the precise network that defines the Detroit Diesel 3-71’s legendary reliability.

Exhaust Manifolds & Related Components

Marine Exhaust Manifold

Detroit Diesel Marine Manifold for 3-71, 6V71, 6V92, 12V92 – New

A properly designed marine exhaust manifold is essential to maintaining the temperature balance of your engine. This heavy-duty manifold is built to withstand high exhaust heat and corrosion from seawater exposure. Manufactured with marine-grade materials and precision-machined sealing surfaces, this manifold ensures a tight fit with the engine head and the exhaust riser.

• Construction: Cast iron or equivalent marine alloy
  
  

• Cooling feature: Water-jacketed design for thermal control
  
  

• Fitment: Compatible with multiple Detroit Diesel two-stroke models, including the 3-71
  
  

• Installation: Simple bolt-on design with matching gaskets and hardware
  
  

Marine manifolds play a crucial role in reducing heat around the cylinder head. A failing manifold can cause exhaust leaks, reduced compression, or even damage to nearby wiring and hoses. Diesel Pro Power provides brand-new, ready-to-install manifolds—not reconditioned or welded units—ensuring long-term durability and performance.

Exhaust Manifold Gaskets

Detroit Diesel Gasket for Exhaust Manifold

Positioned between the cylinder head and manifold, these gaskets create an air-tight seal to prevent exhaust leaks and maintain efficiency. Over time, extreme heat cycles can cause the gasket to shrink, harden, or crack—leading to noticeable exhaust noise and reduced performance.

Features:

• Made from reinforced graphite or composite materials for high-temperature stability
  
  

• Designed to match the 3-71’s unique exhaust port geometry
  
  

• Simple replacement procedure for maintenance crews
  
  

Routine replacement of exhaust manifold gaskets is recommended whenever a manifold is removed. Diesel Pro Power’s gaskets are tested for correct thickness and sealing integrity to ensure a secure fit even under continuous marine duty.

Marine Exhaust Manifold Flanges

Detroit Diesel Marine Exhaust Manifold Flange – 4” NPT Thread

Flanges connect the manifold outlet to elbows, risers, or flexible exhaust hoses. A precision-machined flange helps prevent misalignment, which could otherwise lead to vibration or leaks. This 4-inch NPT threaded flange is corrosion-resistant and ideal for marine exhaust applications where vibration damping and sealing integrity are critical.

Complementary gaskets (like the Detroit Diesel Marine Flange Gasket) ensure a leak-proof joint. Together, these components preserve smooth exhaust flow and reduce wear on the manifold outlet.

Exhaust System Gaskets and Seals

Gasket for Marine Manifold Flange

With an outside diameter of 6.25" and inside diameter of 4.25", this gasket ensures tight sealing between the flange and connecting pipes. The correct gasket not only prevents leakage but also absorbs minor alignment variations and temperature expansion between components.

Gasket for Industrial Exhaust Manifold Flange (3” and 4”)

For industrial installations where dry exhaust systems are used, Diesel Pro Power supplies precision-cut gaskets that maintain tightness even at high exhaust gas temperatures. Made of durable composite materials, these gaskets provide reliable sealing for engines used in generators, pumps, and stationary units.

Marine Exhaust Elbows and Fittings

90° and 45° Elbows for Marine Exhaust Manifolds

Detroit Diesel 90-Degree Elbow – 1” or ¾” Thread

Detroit Diesel 45-Degree Elbow – ¾” Thread

These elbows connect water fittings, manifolds, and risers to direct exhaust gases safely out of the system. Each fitting is precision-threaded to marine-grade standards to ensure compatibility and corrosion resistance.
The 45° elbow is often used where tight clearances demand a smaller angle for smoother routing, while the 90° version directs flow vertically or horizontally depending on the engine’s installation.

Each elbow is made from durable cast brass or bronze alloys that resist saltwater corrosion, ensuring long-lasting performance even in harsh marine environments.

Plates, Plugs, and Water Outlet Components

Marine Manifold Water Outlet Plate
The outlet plate manages cooling water flow within the manifold. In marine applications, proper circulation prevents the manifold from overheating and maintains exhaust gas temperature balance.

Threaded Plate for Marine Manifold (¾” Thread)
These plates serve as access or connection points for water lines. Proper threading ensures reliable sealing when attached to pipes or elbows. Each plate requires two bolts (5/16"–18 x 1⅛") to secure firmly to the manifold body.

Gasket for Series 71/92 Water Outlet
A small yet vital component, this gasket ensures a watertight seal between the plate and manifold. A leaking outlet gasket can lead to saltwater spray and corrosion, reducing the life of the manifold and nearby components.

Industrial Exhaust Flanges and Mufflers

3” and 4” Industrial Flanges

Industrial versions of the Detroit Diesel 3-71 engine often use dry exhaust systems with steel piping and mufflers. Diesel Pro Power offers both 3” and 4” inside diameter flanges to match various industrial setups.

• 3” Flange (5108467): Ideal for compact exhaust routing and smaller engines
  
  

• 4” Flange (5108921): Suitable for high-capacity exhaust systems and generator applications
  
  

Both are precision-machined from heavy-duty materials and tested for vibration tolerance under high-heat conditions.

Mufflers for Industrial Engines

Detroit Diesel Industrial Muffler – 3” NPT

Mufflers play a dual role—reducing noise and ensuring safe discharge of exhaust gases. Diesel Pro Power’s mufflers are designed to handle the high-velocity flow and heat typical of Detroit Diesel’s two-stroke design.

• Inlet/Outlet: 3” NPT for universal compatibility
  
  

• Design: Corrosion-resistant steel housing
  
  

• Applications: Stationary industrial engines, generators, or auxiliary units
  
  

When paired with matching caps and flexible exhaust hoses, this muffler provides smooth exhaust flow, reduced vibration, and lower operational noise.

Muffler Caps for Industrial Engines

3”, 3.5”, 4”, and 5” Muffler Caps

Muffler caps are essential for preventing water and debris ingress when the engine is off. Especially in outdoor or marine environments, these caps protect against corrosion and blockages that can hinder exhaust performance. Available in various diameters, they ensure proper fitment across all Detroit Diesel 3-71 configurations.

Flexible Metal Exhaust Hoses

Detroit Diesel Flexible Metal Exhaust Hose – 3” x 18”

Flexible hoses allow vibration absorption and compensate for alignment variations between rigid components. This 3" x 18" reinforced metal hose features high-temperature tolerance, smooth internal walls for unrestricted exhaust flow, and durable outer layering to resist corrosion.

Using flexible connectors reduces stress on the manifold and muffler flanges—extending the life of both components and preventing exhaust leaks due to vibration.

Mounting Hardware & Accessories

Manifold Studs, Nuts, Washers, and Crabs

Diesel Pro Power offers the full hardware kit required to install or reassemble your Detroit Diesel 3-71 exhaust manifold system:

• Manifold Studs (7/16”–14/20 x 2.10”) – Secure the manifold tightly against the cylinder head.
  
  

• Manifold Washers – Prevent galling and ensure even torque distribution.
  
  

• Manifold Nuts – Precision-threaded for a secure fit and corrosion resistance.
  
  

• Manifold Crabs – Provide tension and hold the manifold in position under vibration.
  
  

Proper installation hardware is crucial for maintaining sealing integrity and minimizing maintenance downtime.

Heat Insulation and Protection

Manifold Insulation Tape (3” and 4” Width)

Manifold insulation tape is a critical accessory in marine exhaust systems. By wrapping the exhaust manifold, insulation tape helps maintain safer engine-room temperatures and protects surrounding components from radiant heat.

• 3” x 100 ft – 1/8” thick: Ideal for compact installations.
  
  

• 4” x 100 ft – 1/8” thick: Provides extra coverage for larger manifolds or dual exhaust systems.
  
  

Using insulation not only enhances crew safety but also reduces the temperature differential that can lead to condensation and corrosion on nearby metal surfaces.

Additional Accessories

Temperature Switch (Closes at 205°F)
Designed for Detroit Diesel, Cummins, and Caterpillar applications, this temperature switch helps monitor engine heat levels. Thread size: ½” NPT. It activates alarms or gauges when exhaust or coolant temperature thresholds are reached—preventing potential overheating.

Detroit Diesel Green Engine Paint
Restore the authentic Detroit Diesel appearance and protect metal surfaces from corrosion with high-quality green enamel. Available for U.S. and Canadian ground shipping, this durable paint withstands marine humidity and heat cycles.

Mechanical & Electric Gauges
Monitor vital engine data with Diesel Pro’s selection of mechanical and electric gauges—available in 12V and 24V configurations. Keeping track of temperature, pressure, and exhaust flow is essential for maintaining optimal engine performance.

Why Choose Diesel Pro Power for Your Detroit Diesel 3-71 Exhaust Parts

Diesel Pro Power stands as the global leader in Detroit Diesel replacement parts, serving over 40,000 satisfied customers worldwide. Our mission is to make ordering parts for legacy engines simple, accurate, and fast.

When you purchase exhaust components from Diesel Pro Power, you benefit from:

• Guaranteed fitment: Every part is pre-verified for Detroit Diesel specifications.
  
  

• Expert support: Our team understands Series 71 engines inside and out.
  
  

• Global shipping: Parts delivered fast, anywhere in the world.
  
  

• Top-quality materials: All components are new, never remanufactured.
  
  

• User-friendly experience: Easy-to-navigate website with real-time inventory.
  
  

We take pride in providing customers with the confidence to maintain, rebuild, or restore their Detroit Diesel 3-71 engines with genuine-quality parts designed to perform and last.