Category Archives: MEP002A

MEP002A Tips and Troubleshooting

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 […]

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 […]

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 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 […]

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 […]

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 […]

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 […]

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 […]

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 […]

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 […]