Experience
The Power of Diesel

Brand New Cummins
4BT and 6BT Engines

Used & Remanufactured
Diesel Engines

Industry Leading
Warranty

Industrial
Applications

Diesel Engine
Off-Roading Applications

FAQs

Q?

How do you fit a Crate Engine to my appliction?

A.

Swapping in a crate engine that is not the original unit can be challenging but not impossible. When swapping in a different make or model engine you want to make sure you get the best like for like swap as possible. If you have an existing 4BT, 6BT or 6CT Engine we will run the engine serial number to determine the fit of your engine vs. one of our crate engines. What we compare are as follows:

- Rated Horsepower and Governed RPM
- Electronic vs. Mechanical Setup
- Fuel Pump Type
- Fuel Lines
- Flywheel and Flywheel Housing Size, Pitch and Diameter
- Starter Location
- Oil Pan (Front or Rear Sump)
- Turbocharged or Naturally Aspirated
- Gear Train (Front vs. Rear Gear Train)
- Block, Head, Piston Configurations
- 24V vs. 12V Electrical Setups

Typically, we recommend if you have an existing setup we will try to match as closely as possible to what you have or give recommendations on how to go about the swap. Sometimes customers will have to re-use existing parts from the old engine and retrofit our engines to make them fit the application. Common parts replacements include: flipping around the oil pan, flipping over the exhaust manifold and re-routing the turbo mount location and re-using smaller or larger bellhousings. The majority of our engines are 24 Volt which can be used in 12 Volt Applications, however some customer's opt to swap out the fuel solenoids or use a step down converter. This is not necessary but can be done after the fact by the customer.

For automotive customers you must make sure your axels, suspension can handle the weight of the crate engine. We recommend at least a 1/2 axle for our smallest 4BT engines. We also send full schematics on the flywheel housings (SAE #2 or SAE #3) upon request so automotive customers can accurately source adaptor plates to bolt up to whatever transmission used.

We also send customers information guides with all of the specs, pictures and recommendations on performance upgrades. Full build sheets and run test videos are also available upon request. Ultimately it is up to you to determine fit of the crate engine in your application but we try our best to provide as much information possible so you can get the best like for like swap.

Q?

Where are you located at?

A.

We are located in the heart of the Rocky Mountains in Denver, Colorado. Feel free to stop by our facility anytime and we will show you are machine shop and engine remanufacturing facility.

Q?

What is the typical cost savings of surplus engines?

A.

We are an alternative to going to the dealership. The Cummins 4BT, 6BT and CAT 3306 engines haven't been newly manufactured by the dealers in mass quantities in 20+ years. Newer models have replaced legacy engines. That being said dealerships will manufacturer one of these engines for a premium price. It is not uncommon to pay double or triple the price at the dealership for the same engine. By going with a surplus engine from us you save a significant amount of money all the while getting the same engine with the same parts.

Q?

What is your lead time?

A.

We can ship new and used engines as well as new parts the day of order. Remanufactured parts and engines are based upon the production schedule and are usually taken on a case by case basis. In recent years with the amount of work out of the machine shop, we typically will only do repair and return reman engines. Note that orders late in the day are processed the following business day.

Q?

What is the break-in procedure for a new engine?

A.

It is very important not to use a synthetic oil for the first 5,500 miles or so. Synthetic oil's lubricity is thinner than standard oil and will not allow the rings and gaskets to seat properly. During the first year of operation the engine's internal components will expand and contract multiple times while reaching it final structural tolerances. After you get your new engine from us we recommend that you put in under a normal load and get it going. Try not to let the engine idle for extended periods, hard shift or accelerate quickly for the first 5,500 miles or push the engine outside of normal load conditions. Keep an eye on your temperature gauges and be smart about not letting the engine overheat.

Full Break-In Instructions for New or Reman Diesel Engines:

All engines, new or reman, need to be broken in properly to ensure optimum performance. The break-in procedure allows engine parts from different machined surfaces to conform to each other and form a tighter seal.

To properly break-in your new or reman engine, please follow the below procedures. Failure to do so can impact the quality and life of your engine, and can void the warranty.

1. Your new or reman engine is specific to your original engine serial number, however applications may vary. Please verify all freeze plugs are in place prior to installation.
2. PRE LUBE engine prior to start up.
3. Do not use synthetic oil.
4. On initial start up the engine should be run for only 5-10 minutes; the length of time to determine the engine has no leaks and parts are torqued properly.
5. The engine should be placed under moderate to heavy load immediately at variable RPM for the first 200 miles or 3-4 hours. Revving the engine on a stationary truck will NOT build load pressure required for break-in.
6. After break-in It is recommended to drain oil, install new filters and fill with new oil.

Never allow your engine to idle for an extended period of time during break-in. A new or reman engine left to idle or operate under low or no load conditions will contribute to glazed cylinders. When this happens the rings will not properly seat and will contribute to oil consumption, low engine power, and decreased fuel economy. The remedy for correction will be to replace cylinder liners and rings.

It is the responsibility of the mechanic or technician to ensure the correct installation of the new or reman engine. Additionally, all other components/parts/systems that complete the long block during installation should be thoroughly inspected, cleaned, and be deemed suitable for use so the long block engine is not adversely impacted.

Q?

Do you use OEM or Aftermarket Parts?

A.

Our brand new engines are all built with ISO 9001 Certified new and aftermarket parts. On average surplus engines are about 90% OEM 10% aftermarket. The little known secret in the automotive/diesel parts industry is that the OEM brands are the EXACT same parts as the aftermarket companies. Many OEMs haven't made their own parts in 20+ years. Both OEM and Aftermarket Parts are produced in the same factories but simply packaged in different boxes. Our failure rating on aftermarket parts is less than 1% overall. Very rarely do we ever see a warranty issue regarding a parts failure.

Q?

What engine models do you offer?

A.

Big Bear Engine Company's humble beginnings come from the remanufacturing industry. We are a company of precision machinists and engine builders and our specialty lies in engineering of remanufactured diesel engines. The company was originally founded as a division of a larger remanufacturing outfit in Denver, Colorado but spun off as its own entity to focus on the smaller Caterpillar and Cummins diesel engine market. Today we focus primarily on brand new never been run Caterpillar 3306, Cummins 4BT (3.9L) and Cummins 6BT (5.9L) engines. In addition new engines we also offer used and remanufactured options.

Q?

Do you offer high performance engines?

A.

Unfortunately we do not. We are machinists and engine manufacturers first and foremost. Our Caterpillar and Cummins engines are all built to OEM (original engine manufacturer) specifications. This means you will always get an engine that is an exact fit to your application. When you purchase and engine from us we will always match your Engine Serial Number (ESN), Critical Parts List (CPL) or Arrangement Number to the engine you need. The Cummins 4BT is pretty much a universal application where as the 6BT (5.9 L) and CAT 3306 engines have many different variations of the block, head and piston configurations.

For those customers looking for performance upgrades for a 4BT Jeep Swap we offer a list of installation and performance experts who can assist you with upgrades to your engine after purchase. With a 4BT Jeep Swap there are many things you can do such as tweak the lift and profile of the camshaft, upgrade the turbo, and tweak the intercooler and aftercooler systems. Suspension and lift kits are a big "must have" if you are installing a 4BT into a Jeep Wrangler as the engine is 1/3 the weight of the entire vehicle.

Q?

Do you offer gas engines?

A.

We only deal with medium to heavy duty diesel engines.

Q?

Do you offer financing?

A.

Yes, we do have financing available for those who prefer a payment option that preserves working capital. We have multiple companies we can recommend that specialize in truck and engine financing. Some 3rd party companies will work directly with the public, others will only deal with registered businesses.

Financing an engine or parts purchase is relatively simple:

- Conserve cash flow
- Application process roughly takes 24 hours
- Fixed monthly lease payments
- No hidden fees or adjustable rate leases
- Combine engine lease and installation in one payment
- Competitive lease rates
- Tax savings under IRS Section 179

Give us a call and we can walk you through the process.

Q?

Do you install the engines and do service work?

A.

Unfortunately we do not install the engines or do any type of inframe service work. We are a company of engine builders and precision machinists. If you are looking for performance experts or simply a facility to drop in your engine we offer a list of installation partners that can service your new engine.

Q?

Do you ship internationally?

A.

We ship to all 50 States, Canada and Mexico on a regular basis through our distribution centers in Denver, Los Angeles, Houston, Cleveland, Miami, Portland, San Jose and Atlanta. We will ship your parts from the nearest warehouse to your location. If you require blind shipments we also have the ability to complete your request.

We also have the ability to ship parts and engines internationally. We have shipped parts and engines to New Zealand, Brazil, Uruguay, Russia and the Virgin Islands to name a few places.

Check out our shipping page for more information about freight shipments.

Q?

What is your warranty policy?

A.

We have one of the strongest warranties in the diesel engine business.

  • Remanufactured Engines - 1 Year Unlimited Miles; first six months parts and labor, second six months parts replacement.
  • New Engines - 6 Months Unlimited Miles Parts Replacement
  • New Parts - 2 Year Unlimited Miles Warranty

You can read the full warranty in detail here.

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