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Cat 3066 Engine

CAT 3066 Engines For Sale

CAT 3066 EngineThe Caterpillar 3066 Engine is a reliable engine capable of pushing out a gross power of 143 hp. The design of this engine was intended to aid the comfort of the operator by reducing the amount of sound and vibrations produced by the engine. The Cat 3066 is a Six-cylinder turbocharged engine built for power, reliability, economy, and low emissions that will keep the application running at peak performance.

Engine Applications and Uses

  • Construction
  • Industrial
  • Agricultural
  • Heavy Equipment

Common CAT 3066 Engine Problems & Failures

Customers who hope to replace their 3066 Cat engines usually have a motivation for doing so, over time we have pinpointed common themes and issues that are often reported as the reason someone would wish to replace their Cat 3066. Considering this, we have assembled a list below of these issues, some of which sadly mean the engine is at the end of the road, but some are of course fixable.

AERA Association Member

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

Caterpillar 3066 Engine Replacement Options

There are several issues that could harm your engine, some leaving you with no choice but to replace it, and some only requiring a few new components. Furthermore, in the absence of these aforementioned instances, maybe your Cat 3066 engine just needs a well-earned refreshment.  Of course, cost, time, and availability will affect your decision making so let us inform you of the pro’s and con’s of a new engine from the dealer.

Remanufacturing Process

A remanufactured 3066 cat engine long block would be a wise choice for someone who has had the misfortune of suffering a severe breakdown, especially if there are some re-usable external parts from their old motor. What is more, it is a great alternative if you’re working to a budget.

Our team of dedicated machinists and engine builders will execute a full core tear down, cleaning, inspection, and machining of the Caterpillar 3066 engine before it even leaves our facility. This ensures perfection each and every time. This also retains both our quality of product and high level of professionalism.

Our method of remanufacturing at 3066’s means they are constructed with both Reman and new parts. Please note, we do not recondition or refurbish old engine parts, rather, we completely rebuild the old Caterpillar 3066 Engine motor back to OEM specs.

Thorough Cleaning

To produce something of great quality, the original components must first be in good working order. To accomplish this. Every Caterpillar 3066 engine is entirely stripped. Blocks, heads, rods, crankshafts and camshafts are carefully cleaned in a chemical jet wash or hot tank to get rid of any impurities that could facilitate both early component and engine failure.


The Cat 3066 crankshafts will be precision machined to exact tolerances, polished & magnafluxed, then thoroughly inspected by our quality control department to ensure quality is maintained.

Cylinder Heads

It is imperative that the final product is compatible with all modern gasket materials. Therefore, the heads are resurfaced to ensure a proper sealing surface with the block and a finish compatible with modern gasket materials. Valve height for Caterpillar 3066 is mic-d and every head is vacuum tested to assure correct valve seating.

Cylinder Blocks

The 3066 Cat Engine blocks are closely inspected by magnetic particles for any cracks and imperfections. Cylinders are bored, fastened and inspected for the precise tolerances. Torque plate honing is executed on some engines to eliminate the possibilities of any cylinder head distortion after the head is bolted and torqued to the block. This process makes certain that a major cause of engine blow-by is eliminated. Block surfaces are then machined and then inspected to ensure proper finish.


Camshafts are then examined and accurately machined to provide correct lift for the Caterpillar 3066. Lobs are calculated with a micrometer to ensure OEM tolerances are met.

Connecting Rods

Cat 3066 connecting rods are thoroughly cleaned, machined to O.E.M. specifications, then honed to the standard diameter of original equipment to ensure even distribution of stress on the bearings. New bushings are also fitted and machined in all bushed rods. Every rod is then carefully inspected for any bend and/or twist.

New Parts

All Caterpillar 3066 Engine long block engines will receive a number of new parts as standard. These include pistons and rings, bearings, gaskets and seals, and liners. New parts assure dependable performance and reliability throughout the life of your engine. The new parts are a blend 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

For the finest result, our remanufacturing process aims to make the engine as close to new as possible. Wearable parts are routinely replaced. All Cat 3066 core material is carefully inspected and examined against the original equipment specifications for the correct dimensional tolerances. Replacement parts are either new or requalified. We also mirror the same production processes the original equipment if new parts are required. Testing is then performed to manufacturer specifications and original production standards.

CAT 3066 Long Block Parts List:

  • Timed Front Gear Group
  • Cylinder Block
  • Crankshaft
  • Connecting Rods
  • Complete Loaded Cylinder Head
  • New Upper and Lower Gasket Set
  • Intermediate Cover
  • Camshaft
  • Followers/Lifters
  • 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 3066 Spec

Engine Data

Flywheel Power103 kW (138 hp)
Bore102 mm 94.02 in)
Stroke130 mm (5.12 in)
Displacement6.37 L (389 cu in)
Gross Power107 kW (143 hp)
EmissionsUS Tier 2 and EU Stage II

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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