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Cat 3406 Engine

CAT 3406 Engines For Sale

CAT3406 Engine

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

Engine Applications and Uses

  • On Highway Trucks
  • Industrial Applications
  • Marine

Common CAT 3406 Engine Problems & Failures

We tend to see some themes in customers who wish to replace their Caterpillar 3406 engines. So, to put this to good use, we have compiled a list of common problems that are frequently reported. Some of the issues featured below may mean your engine has run out of time, however, some may also be salvageable if caught in good time.

AERA Association Member

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

Caterpillar 3406 Engine Replacement Options

Sometimes the truth is your engine is beyond saving, there are numerous causes than can harm your engine, but not all mean your engine is KIA. At times, your 3406 Cat engines may just need a few new parts, or maybe it just needs a little refreshment to keep it in good condition. We understand that factors such as time, money, availability, etc. will all impact your decision making. Therefore, we have provided some insight by providing both pro’s and con’s of a new engine from a dealer.

Remanufacturing Process

For those of you reading this that are unfortunate enough to have seen your engine endure a catastrophic failure, a remanufactured Caterpillar 3406 long block engine would be the ideal remedy. Moreover, if you have good re-usable external components that are still functionable, then these can be salvaged from your beloved 3406 Cat Engine. Most importantly, this would be a good alternative if your trying to save some money.

Big Bear Engine Company always uphold a professional level of service, whatever the task. In the sphere of remanufacturing, we ensure this level of quality is upheld by first executing a full core tear down, cleaning, inspection, and machining of the CAT 3406 engine. This is carried out on every engine before it leaves our facility.

It is important to note, that all of our Caterpillar 3406 engine remanufactured long blocks are built with both reman and new parts. Therefore, we do not just recondition or refurbish old parts, instead we entirely rebuild the old 3406 Cat engine back to its original OEM specs.

Thorough Cleaning

Caterpillar 3406 EngineThorough cleaning is imperative in the process; therefore, we endeavor to rid your engine of any impurities that could contribute or cause both component failure or engine failure. This is accomplished by stripping the 3406 Cat engine, then putting the blocks, heads, rods, crankshafts, and camshafts through a chemical jet wash or hot tank.


Before our quality control department inspect the final product, the crankshafts are precision machined to the precise tolerances, polished and magnafluxed.

Cylinder Heads

Heads are resurfaced to guarantee a proper sealing surface with the block and a finish compatible with today's new gasket materials. Valve height is mic-d and every head are vacuum tested to assure correct valve seating.

Cylinder Blocks

The magnetic particle that forms the block is inspected for any cracks or further damage. The cylinders and then bored, honed, and again inspected to the specific tolerances. Torque plate honing is performed on particular engines to eliminate the chances of cylinder head distortion after the head is bolted and torqued to the block. This process eliminates the main cause of engine blow-by. Block surfaces are then machined and inspected to ensure proper finish.


Camshafts are inspected and precisely machined to provide correct lift. Lobs are measured with a micrometre to make sure OEM tolerances are met.

Connecting Rods

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

New Parts

Good performance and reliability are what we strive for, therefore, all 3406 Cat engines will receive a set of new parts such as pistons and rings, bearings, gaskets and sealers, and liners. These parts consist of both OEM and Aftermarket 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, wearable parts are automatically replaced. All 3406 Cat engines core materials are thoroughly inspected and examined against original equipment specifications for correct dimensional tolerances. Replacement parts are new or requalified. If new, parts are made in the same production processes as original equipment. Testing is performed to manufacturer specifications and original production standards.

CAT 3406 Long Block Parts List:

  • CAT 3406 EngineCylinder Block
  • Complete 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 new oil pumps, oil coolers, water pumps, turbos, injectors and fuel pumps for additional cost with the long block but 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 Spec

Engine Data

Minimum Power 280.0 bkW
Maximum Power 347.0 bkW
Rated Speed 1800-2100 rpm
Emissions noncertified
Engine Configuration Inline 6, 4-Stroke-Cycle Diesel
Bore 137.2 mm (5.4 in)
Stroke 165.1 mm (6.5 in)
Displacement 14.64 L (893.39 cu in)
Aspiration Turbocharged Aftercooled
Compression Ratio 14.5:1
Rotation (from flywheel end) Counter-Clockwise
Lube System – Refill 34.1 L (36 qt)
Length 1660 mm (65.35 in)
Width 906 mm (35.67 in)
Height 1335 mm (52.56 in)


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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