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Mack E7 Engine

Mack E7 Engines For Sale

The Mack E7 engine was first conceptualized in 1988 by Mack Corporation engineers and then officially introduced in 1989. The Mack E7 Engine replaced the Mack E6 model and was produced over a span of 20 years. The engine was predominantly used in commercial 18 -wheel trucks. Over its period of production, the engine was subject to some reformations until it was finally ceased in early in the 21st century. The Mack E7 was one the most popular industrial diesel engines of all time.

Both large scale and small-scale operations flocked to the Mack E7 Engine because of its reliability and fuel efficiency. Up until 1999, Mack ended up producing 16 different variations of the E7. Mack E-Tech engines are still being produced today and still retain their reputation for their outstanding horsepower to weight ratio. Mack E-Tech engines are 6-cylinder multi-system cooled. The typical horsepower rating for the used Mack E7 engines we provide for sale, is between 250-400 hp.

Engine Applications and Uses

  • Mining
  • Oil & Gas
  • Agriculture
  • Construction
  • Industrial

Common Mack E7 Engine Problems & Failures

We tend to see some themes in customers who wish to replace their Mack E7’s. So, 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 Mack E7 engines 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
  • Extreme Blow By
  • Dropped Valves
  • Camshaft Failure
  • Crankshaft Failure
  • Lifter/Roller Failure
  • Connecting Rod Failure

Mack E7 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. Sometimes, your Mack E7 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 influence 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 E7 long block would be the perfect remedy. Moreover, if you have good re-usable external components that are still functionable, then these can be salvaged from your beloved E7. Most importantly, this would be a good alternative if your trying to save some money.

We 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 engine. This is carried out on every engine before it leaves our facility.

It is important to note, that all of our E7 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 E7 engine back to its original OEM specs.

Thorough Cleaning

Thorough cleaning is imperative in the process; therefore, we strive to rid your engine of any impurities that could contribute or cause both component failure or engine failure. This is achieved by stripping the E7, 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 is vacuum tested to assure correct valve seating.

Cylinder Blocks

The magnetic we use is used to pick up even the slightest of defects, therefore this is used when the block is inspected for any cracks or additional 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 micrometer 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 fitted 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 E7 engines will receive a set of new parts such as pistons and rings, bearings, gaskets and sealers, and liners. These parts of the used Mack engines for sale consist of both OEM and Aftermarket when available.

Request a Quote

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 aim to make as close to new as possible. In pursuit of this, Wearable parts are automatically replaced. All E7 core material is 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.

Mack E7 Long Block Parts List:

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

MACK E7 Spec

Engine Data

Bore123.83 mm (4.875 in)
Stroke165.10 mm (6.5 in)
Displacement728 CID (12.0 L)
Compression Ratioup to 375 hp = 16.5:1, above 375 hp = 15.3:1

Give us a call today at 844-340-4114 to view our Mack E7 engines we have for sale or 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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