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Cat 3406 Engine

CAT 3406 Engines For Sale

Yellow CAT 3406 Engine Side View

The 3406 CAT Engine was designed to power heavy vessels and can be used as a single unit or coupled to generate more power. The Caterpillar 3406 engine can produce a maximum output of 347.0 bkW (465 hp) and, is commonly seen in marine applications powering large yachts, cruise ships, and freight transportation vessels. The engine is also frequenty found in on-highway trucks and various industrial off-highway equipment such as dozers, scrapers and mining equipment.

Engine Applications and Uses

  • On-Highway Trucks
  • Industrial Use
  • Marine Vessels

Common CAT 3406 Engine Problems and Failures

Here at Big Bear Engine Company, we tend to see certain pattern problems that often lead to customers replacing their Caterpillar 3406 engines. Some of the issues below may mean your engine has run out of time. However, in other instances parts of the engine can be salvageable if caught in time.

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  • Spun Crankshaft Bearings
  • Cracked Cylinder Head
  • Scored Pistons and Liners
  • Overfueling
  • Lack of oil (orno oil pressure)
  • Camshaft Failure
  • Crankshaft Failure
  • Dropped Valves
  • Extreme Blow By
  • Lifter/Roller Failure
  • Connecting Rod Failure

Caterpillar 3406 Engine Replacement Options

There are a host of issues that can harm your engine, but not all of them mean your engine is unsalvageable. While certain engines are beyond repair at times, some just need a few new parts, or a refresh. We understand that factors like time, money, and availability will factor into your decision making when it coes to purchasing a new engine. This is exactly why we offer remanufactured long blocks.

CAT 3406 Engine Replacement Options

The Big Bear Remanufacturing Process

For those of you reading this that had the unfortunate luck of your engine suffering a catastrophic failure, our remanufactured Caterpillar 3406 long block is the ideal remedy. Better yet, if you have good, fully functional and re-usable external components, they can be retained from the original 3406 Cat Engine. Most importantly, our long blocks are a great alternative if you're trying to save some money.

We're a company that's renowned for always upholding a professional level of service, whatever the task. In the sphere of engine remanufacturing, we ensure this level of quality is upheld by first executing a full core tear down, followed by comprehensive cleaning, inspection, and machining of your CAT 3406 engine. This extensive qulaity control process  is carried out on every engine we build.

It's important to note that all of our Caterpillar 3406 engine remanufactured long blocks are built with both reman and new parts. We do not just recondition or refurbish old parts. Instead, we completely rebuild your old 3406 Cat engine back to its original OEM specs.

Thorough Cleaning

CAT 3406 Engine With a Plastic Wrapper Thorough cleaning is imperative in the engine rebuilding process. Our goal is to spot any impurities or potential structural flaws that could contribute or cause both component failure or engine failure. This is performed by stripping the 3406 Cat engine and then putting the block, head, rods, crankshaft, and camshaft through a chemical jet wash or hot tank.


Before our quality control department performs a full inspection of the final product, the crankshafts are precision machined to the exact tolerances, then polished and magnafluxed.

Cylinder Head

Each head is resurfaced to guarantee a proper sealing surface with the block - and to provide a finish that's compatible with present-day gasket materials. Valve height is mic'd and every head is also vacuum-tested to ensure correct valve seating.


Magnetic particle inspection is a common practice for any reputable engine builder, and we magnaflux each crankcase to inspect for any cracks or further damage prior to the begin of the build. The cylinders are then bored, honed, and inspected once again. Torque plate honing is also performed on particular engines in order to eliminate the chances of cylinder distortion after the head is bolted and torqued to the block. This process eliminates the primary cause of engine blow-by. Block surfaces are then machined and inspected to ensure a proper finish.


Camshafts are inspected and precisely machined to provide correct lift. Lobes are measured with a micrometer to make sure that all OEM tolerances are met.

Connecting Rods

Each connecting rod is carefully analyzed for signs of bend and/or twist.In order to achieve even distribution of stress across the bearings, the connecting rods are cleaned, machined to OEM specs, and then honed to the standard diameter of the original equipment. New bushings are also equipped and machined in all bushed rods.

New Parts

Fresh pistons and rings, bearings, cylinder liners, gaskets, and seals come standard on all of our reman 3406 Cat engines. These brand-new parts ensure dependable performance and reliability throughout the life of the engine. The new parts are made up of a combination of both OEM and aftermarket components, when available.

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Please fill out the form below with your information and request. A member of our staff will be with you shortly.

Remanufactured Engines Standards

To best define remanufacture, would be to make these CAT 3406 engines as close to new as possible. In pursuit of this, all wearable parts are automatically replaced. All 3406 Cat engines core materials are thoroughly inspected and examined against original equipment specifications for correct dimensional tolerances. Every replacement part is new or requalified. If new, parts are made using the same production processes as original equipment. Testing is performed to manufacturer specifications and original production standards.

CAT 3406 Long Block Parts List:

  • Yellow CAT 3406 Engine on top of a Wooden PlatformBlock
  • Cylinder Head (Complete and Loaded) Cylinder Head
  • Intermediate Cover
  • Camshaft
  • Connecting Rods
  • Crankshaft
  • Followers/Lifters
  • New Upper and Lower Gasket Set
  • Timed Front Gear Group
  • Pistons
  • Liners
  • Rings
  • **1 Year Warranty

*Note: We can provide a new oil pump, oil cooler, water pump, turbo, injectors and fuel pump for additional cost with the long block, but those components will not come assembled to the engine.

**First 6 Months Parts & Labor, Second 6 Months Parts Replacement Only. Ask your sales representative for a full copy of our remanufactured long block warranty.

CAT 3406 Specs

Engine Data

Minimum Power280.0 bkW (375 hp)
Maximum Power347.0 bkW (465)
Rated Speed1,800-2,100 rpm
Engine ConfigurationInline-6, 4-Stroke-Cycle Diesel
Bore137.2 mm (5.4 in)
Stroke165.1 mm (6.5 in)
Displacement14.64 L (893.39 cu in)
AspirationTurbocharged, Aftercooled
Compression Ratio14.5:1
RotationCounter-Clockwise (from flywheel end)
Lube System – Refill34.1 L (36 qt)
Length1660 mm (65.35 in)
Width906 mm (35.67 in)
Height1335 mm (52.56 in)

Yellow CAT 3406 Engine Tied Black Rope

Give us a call today at 844-340-4114 for immediate sales and support for the Cummins 4BT, Cummins 6BT, 6CT, ISC, 855, QSB 4.5 L or CAT 3306. If you have any questions check out our FAQ Page. We are always ready to help or just listen to your crazy off-roading adventures!

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