List of Lister Petter Engines and Their Specifications

Model Cylinders Capacity (cc) Bore & Stroke HP @ RPM (max) Cooling Weight Fuel Combustion/Injection                   Lister Petter AA1 1 219 23/4 X 21/4 3.5 @ 3600 Air 93 lb Diesel Indirect Petter AB1 1 261 3 X 21/4 5 @ 3600 Air 98 lb Diesel Indirect […]

GMG Has Expanded Our Refurbishment and Repair Capabilities!


(Halifax, Vermont) GMG is pleased to announce that we have expanded our capabilities in both man-power and space to repair any MEP generator (or any other generator for that matter). We have the absolute best technicians on staff and they are all EGSA certified! This means they KNOW what they are doing. There are less […]

Finally! GMG Has Created a Rebuild Kit for the MEP016B – MEP701A Injection Pump

MEP016B - MEP701A - Injection Pump Rebuild Kit - Bosch-PFR1K80A505-Pump-0414181033

We are expecting our first batch of rebuild kits by the end of December, 2018. If interested, please contact GMG to get on the list. We had to source this from Europe. Bosch no longer makes this pump (as of 2017), so rebuilding is the primary solution at this point. GMG has been unable to […]

A Super-Powerful 24v Smart Battery Charger, Maintainer & Desulfator 1A/2A/4A AGM GEL WET


Winter is coming! Check your batteries NOW! A top 3 problem for generators is battery failure! Take care of your batteries and they will take care of your generator, which will take care of you! This 24v battery charger is ideal for all 24v battery setups found on all US Military Generators. GMG has personally […]

We Have a Limited Number of Aux Fuel Lines 25′. These Are Milspec!

MEP Generator Aux Fuel Hose NSN 4720-01-215-0816, 111417-5S-2992, MS28741-5-2992, MIL-DTL-8795

We have a limited number of aux fuel lines for all MEP generators, both new and past generations. This is a 25′ hose with field install-able Eaton fittings. Get one while they last! You can follow this link to purchase: MEP Generator Aux Fuel Hose NSN 4720-01-215-0816, 111417-5S-2992, MS28741-5-2992, MIL-DTL-8795  

Is DRS or Fermont Making Generators Anymore (e.g. MEP803A, MEP802A)


We get this question a lot. The short answer is no and the new company who purchased DRS Fermont, Leonardo DRS, has not been making these units for a few years. In addition, they are not supporting theses products with spares. Hopefully, GMG can help with your spare parts for your MEP803A and spare parts […]

GMG Is Pleased To Announce Our New Ambac M50 Pump Exchange Program


GMG is now fully remanufacturing Ambac M50 pumps to OEM specs and fully testing them. Pumps come ready for 2 and 4 cylinder installations. We are providing a $50 core credit for any rebuildable core. You can purchase a remanufactured MEP002A-MEP003A Ambac M50 Fuel Injection Pump 50-2/4A-80A-9540A here.

208V Single Phase and 208V 3 Phase: Can I Run Single Phase Loads with a Three Phase Generator? Yup.


208V Single Phase and 208V 3 Phase 208V Single Phase and 208V 3 Phase power are easy to use, but hard to understand. If you want a simple understanding but aren’t electrically minded, start with a simple analogy you can build on. I like the bicycle analogy. Bicycle Analogy   A tandem bicycle has two people providing power with four legs (pedals). Each leg […]

U.S. Military Connector Specifications Including MIL-DTL-22992


U.S. Military connector specifications including MIL-DTL-22992 Many customers inquire about the various military connector specifications in use by the US (and other) military. Below is a detailed explanation of the most common standards. GMG can obtain all current cables, connectors, and leads for US military diesel generators and distribution boxes. Note that the following specification and […]

Helpful Manuals, Information, and Videos to Help Install GMG MEP Auto-Remote Start Kits

[gview file=””] Helpful videos relevant to all MEP auto-remote start kits: Discussion of the main three pole breaker: Discussion of low oil pressure shutdown scenario, part 1: Discussion of low oil pressure shutdown scenario, part 2: Discussion of external contactor within ATS that actually shifts load: Discussion of external contactor and ATS (automatic transfer switch):  

GMG Opens Warehouse Distribution and Shipping Center in Ohio


(Halifax, Vermont – May 27, 2016) Green Mountain Generators (GMG) is proud to announce the opening of our Midwest Operations Center in Stow, Ohio. This new facility is strategically located close to two of the largest US Military Warehousing and Liquidation Centers in the United States and allows GMG to procure and warehouse military equipment […]

GMG Fixes a Blown Oil Pump in a MEP003A – The Benefits of Our Warranty Program


GMG recently fixed a blown oil pump in a customer’s MEP003A. Bad things can happen, even though we refurbish and load-bank a unit. Under our exclusive warranty program, we covered this repair. Typically, we only cover parts (not labor) in any warranty situation, but we made an exception and covered labor costs, which were over […]

MEP804A Use of Diagnostic Pin Connectors As a Diagnostic Tool


In most of the manuals of the new generation units, you will find a detailed breakdown of the use of the diagnostic pin tool connector. You will see the mapping of each of the many pins and how they can be used to test various circuits and functions of the generator. For example, for the […]

My MEP002A – MEP003A Batteries Are Not Recharging, Fuse Keeps Popping, Maybe Voltage Regulator or Stator is Bad. Help!


We get a number of inquires about the following on MEP002A and MEP003A units, but many other military units have similar setups and issues. Here are the symptoms: Dual 24v battery set up is not working. Batteries will not charge and/or are dying or dead. In-line fuse for battery charging system keeps popping out. Voltage […]

So how do the MEP002A and MEP802A compare for noise? Listen for yourself

We get this question a lot:  So how to MEP002A units compare to their new generation counterpart in terms of sound level? The former doesn’t have a sound kit (ASK = Acoustic Suppression Kit) and the latter does. Listen for yourself. It is a material difference, but the MEP002A is not nearly as loud as […]

My Generator Starts When Cold, But Not When Hot!


We live in a crazy world! I thought warm diesel engines should start easier than cold ones?! “My Generator Starts When Cold, But Not When Hot!” That is a true statement and remains true. The problem might not lie in the engine itself or the injectors or the injection pump or anything related to the […]

Army to Deliver Fuel-Efficient Generators to Afghanistan


Below is a press release of the US Army regarding the new AMMPS (Advanced Medium Mobile Power Sources) program which replaces the TQG (tactical quiet generator) program (aka 2nd Generation of MEP – mobile electric power).  This will be the 3rd major formal MEP program in US Military History.  Roughly 2,000 new units are in […]

Cummins Is Focused on the Military Market with AMMPS Generators


The new generation of military generators is no entering full production. Cummins is the initial manufacturer. More information is needed to determine who will make the various components. In the MEP802A and MEP803A models, Lister Petter, which is now in bankruptcy (again),  made the core engine and fuel injection components.  This has led to a […]

Wiring Diagrams for MEP002A & MEP003A Military Diesel Generators


We have had requests for diagrams for the MEP002A and MEP003A wiring.  In this post you will find 3 high resolution photos of a new Control Box that we have in stock (yes, it’s for sale;-). Hope this helps you with your electrical needs.

Can I Run My 120/240V Wired House With A 120/208V Three Phase Generator?

Below is a great video that concerns itself with answering this oft-asked question. Many military generators are only configured to output three phase electricity, especially the larger units including the MEP004A, MEP005a and up.  Note that the MEP002A and MEP003A models output single phase 120/240V single phase power just fine and are not the focus […]

How To Convert a MEP016D to 120/240 Volt Use

There is a lot of chit chat on the web about converting the MEP016D military diesel generator to dual/simultaneous 120/240 volt output. The normal output is either 100% 120 volt or 240 volt (both single phase), but not both. Before going further, some disclosures: GMG always recommends the hiring of a local licensed and insured […]

How To Break-In a New Re-manufactured Engine or a New Refurbished Generator from GMG


We get this question A LOT!  Some customers buy new MEP002A or MEP003A re-manufactured engines from GMG. Some buy our refurbished generators complete. In either case, we recommend a Break-In period, especially for re-manufactured engines.  For refurbished generators, we recommend an early oil change in the 50 hour range (vs the normal 100 interval) to […]

What Does GMG Recommend for Diesel Fuel Additives for Military Diesel Generators?

                We get this question a lot. There are many good products on the market and regional availability is an issue. You want to choose an additive that is in good supply in your area (your country).  We recommend using Power Service products in general and recommend using […]

We Have Onan Diesel Fuel Injectors In Stock! Onan/Yanmar 147-0136


Is your generator (MEP002A or MEP003A) sputtering?  Is it coughing smoke in a rhythm?  If it is, it could very well be time for new injectors that will improve the performance of your generator dramatically.  We now stock this very difficult to find injector. It was made by Onan in the early days and was […]

Re-energizing Dead Generators

Two methods for field-flashing generators, one using an existing 110 volt source, one using an electric drill – by End Times Report Home generators in storage can “go flat” or lose their magnetism. Then they will not produce electricity, even though the small gasoline engine turning them is running just fine. There is a simple way to fix […]

GMG Announces New Generator Service Partner: Powers Generator Service

[Halifax, Vermont: September 16, 2013] GMG has been working hard establishing partnerships for both services and for parts.  We have established dozens of partners for parts and service across the US and Europe.  Today, we are happy to announce that GMG has formed a service relationship with Powers Generator Service, headquartered in Swanzey, NH.  Powers has […]

My Generator Is Not Generating, But The Engine Runs; Help!


One of our recent customers had a small scare with their new generator. Nothing dramatic, just puzzling. The engine started normally and everything seemed 100%, except for one issue:  no electricity was being generated to the main terminals or the convenience outlet.  Frustrating to say the least. The customer and GMG tried most of the […]

The World’s Smallest Portable Diesel Generator: The Dewey Electronics MEP-531A for the US Military


OK, maybe it’s not the lightest, but I would say it’s the smallest generator of it’s kind.  A tried and true electricity in a box product. Simple, extremely rugged, intelligent and, most of all, mobile.  In deciding to stock this product, we had to think of a lot of factors.  Those included: Dealing with higher […]

All Military Generators – All in One Place!


We have finally assembled what we believe is a relatively exhaustive list of past and present generators used by the US Military.  On this page, you will also see links to two versions of the: STANDARD-FAMILY-OF-MOBILE-ELECTRIC-POWER-GENERATING-SOURCES-GENERAL-DESCRIPTION-INFORMATION-AND-CHARACTERISTICS-DATA-SHEETS-MIL-HDBK One version was published in 2010 (MIL-HDBK-633A) and one published in 1998 (MIL-HDBK-633).  Both of these manuals have very […]

We Have Glow Plug Kits for MEP-002A and MEP-003A Diesel Generators


We have them. They aren’t cheap, but they will help keep your unit 110% in the winter and cold starts. These will also help save your starter from over-working (same goes for your batteries). Follow link to purchase MEP-002A and MEP-003A 24v Glow Plugs.

Fuel Line Check Valve Problems


Many military generators have check valves in the fuel line system, often immediately after all of the filters, strainers, but before the injector pump. This prevents fuel from flowing backwards in the system and also helps the system hold its prime. The MEP-002A and MEP-003A units have a check valve located after the third filter […]

GMG Approved For International Exports

[Halifax, Vermont: February 15, 2013]  GMG has recently obtained approvals from the U.S. Department of Defense, the U.S. Department of State and the U.S. Department of Commerce (specifically, the Bureau of Industry and Security) to export demilitarized generators globally (with specific exceptions such as Iran, North Korea, Cuba). This has taken considerable time and effort to […]

Installation, Service, Maintenance Now Available Through Partnership with FM Generator

[Halifax, Vermont: February 15, 2013]  GMG is proud to announce a new partnership with FM Generator, Inc.  FM Generator, Inc. has been selected by GMG as a premier service provider to complement GMG’s products.  We have had many customers inquire about whether GMG can help install, maintain and design custom power solutions. Many of these […]

How Noisy Are MEP002A and MEP003A Military Diesel Generators? The Same As Honda’s Best Worksite Unit!

GMG gets this question a lot!  Many opinions can be had about the noise level of MEP-002A and MEP-003A diesel generator units. To protect your hearing around any engine or machinery, wear hearing protection! It’s cheap and your friends and family will thank you when you’re not screaming at them or the TV is blasting! […]

How To Wire a MEP002A or MEP003A Diesel Generator

This article describes common power  generation connections and discusses the use of power transformers.  This is a scanned article and there may be typos and some odd images. We tried to scan and convert this so that it is more accessible on the Internet.  Please see all the figures and pictures at the end of […]

A Simple Generator Setup for Home Back-up Use


This is a great example of a MEP003A installed for home use.  The unit is place on high ground that will drain well.  Then the entire area is covered with crushed stone to aid in water transport and to minimize mud kicking up on the unit.  4 modest sono-tubes are sunk in the ground to […]

A Word About Our Batteries

Below are the specs for civilian batteries for the MEP003A and MEP002A generators: MEP003A Units: Battery BCI # : BCI #24R Battery Height : 9″ Battery Length : 10 3/4″ Battery Voltage : 12 Volt Battery Width : 6 3/4″ Battery Cold Cranking Amps @ 0 Degrees F : 675 Battery Cranking Amps @ 32 Degrees F : 850 Battery Posts Type : Top Post Battery Reserve Capacity (Minutes) : 115 Battery Weight : 40 lbs […]

GMG Now Offers 90-Day – 100-Hour Warranty for Generator Sets

[Halifax, Vermont: November 8, 2012] Effective immediately, all new customers who purchase a generator set from Green Mountain Generators will receive a 90-day / 100-hour warranty (whichever comes first).  The warranty only covers mechanical problems to the entire generator set.  If there is a problem, you may contact GMG through our website. Please explain your issue […]

New Ambac M-50 Manuals Posted


These manuals are for servicing your Ambac M-50 Fuel Injection Pumps for your MEP002A or MEP003A units. Not that we recommend that the average person attempt to service or rebuild your injection pump, but we want to provide all of the manuals we can find for you.  GMG will begin to offer a rebuild program […]

GMG Launches Exclusive Lifetime Parts Discount Program

GMG Lifetime Parts Discount Program: [Halifax, Vermont: October 17, 2012] GMG is proud to announce the establishment of the “GMG Lifetime Parts Discount Program.”  It is effective immediately and is retroactive to all of the many customers who have previously purchased generator sets. All customers who purchase a complete generator from Green Mountain Generators will receive 10% […]

Selecting Correct Injection Pump Timing Button and Injection Pump Installation for you MEP-002A or MEP-003A Ambac Fuel Injection Pump

Selecting Correct Injection Pump Timing Button and Injection Pump Installation for you MEP-002A or MEP-003A Ambac Fuel Injection Pump M50/PSU IF NO. 3136 1/21/2009 1 Printed in USA Rev Level A Ambac International, 910 Spears Creek Court Elgin SC 29045(USA) – North America Telephone: 1-800- 628-6894 Fax: 1-800-542-8230 Website:   DOWNLOAD THIS FILE:  Ambac-Timing-Button-For-M50-Injection-Pump-MEP002A-MEP003A-IF_No._3136 Selecting Correct […]

Electric Motors and Power Systems

There seems to be a lot of confusion about the voltage standards for motors and why they are structured the way they are. There are, of course, two broad categories of motors, AC and DC. The voltage standards for these two decidedly different motors are much different from each other. It will be the goal […]

Fuel Consumption For Diesel Generators


This chart estimates diesel fuel consumption for a generator based on the size of the generator and the load at which the generator is operating.  Please note that this table is simply an estimate. Many other factors will affect the fuel efficiency of a diesel generator including design, fuel quality, air quality, and frequency of […]