Head Lamp Wiring

Another question arises from Texas and Luxembourg which brings me to resurrect some old notes.

The wiring along the inside of the Left Hand Front Fender (Mudguard) consists of three wires that run from the six (6) post junction block on the firewall to the two (2) post junction block on the inside front of the Left Hand Fender.

The type of casing of this three (3) wire harness is the question sometimes asked and it can be either wire braided or taped with original style black harness tape.

The question relates as to which one was used first and when was the changeover made.

Now before I put my views forth it is not my intention to start an argument as to the serial number when the change was made. There are different opinions on that matter by either very knowledgeable people and others as to whether the books, manuals, parts lists, etc. are right or wrong. Or what was found on a particular Jeep that proves everything everyone else believes is questionable except the person wanting to prove their very own opinion.

The facts are there were changes, the dates were approximate and it’s up to you, the restorer, to make up your own mind, after all it’s your Jeep, do it your way and sleep at night knowing you are happy.

Early production Jeeps used the wire braided harness, Willys Part Number A-1665 (GPW-14425).

Later production Jeeps used the black taped harness, Willys Part Number A-7825 (GPW-14425-B).

Willys MB up to approximately 238835 around June, 1943 we suggest should have the metal braided A-1665 harness.

Willys MB after 238835 or after June, 1943 should have the black taped A-7825 harness.

GPW’s changed from approximately early 1944, but as Ford was following Willys instructions on changes they usually lagged behind and Ford generally did not document the change dates at all.

We produce thousands of wiring kits at a time as follows:

A-2000A kits which fit early Willys MB’s and GPW’s – we include the wire braided A-1665 harness.

A-2000B kits which fit later Willys MB’s and GPW’s with the Push/Pull Headlight Switch – we include the A-7825 black taped harness.

A-2000C kits which fite late Willys MB’s and GPW’s with the Rotary Headlight Switch – we include the A-7825 black taped harness.

Please understand it is difficult for dealers worldwide to hold every variance a restorer might require. If you require, for instance, an A-2000B kit with the wire braided A-1665 harness ask your dealer and they will make every effort to assist you or order your kit from M.V. Spares on www.mvspares.com and we will ensure you receive what you need.

I would like to take this opportunity to point out that not all wiring kits using the M.V. Spares part numbers A-2000A, A-2000B and A-2000C are of our high quality production.

The kits sold under the name Seal Tested are poor quality copies. Using our part numbers without our permission and inserting our wire descriptions and other instructions in these Indian made kits does not raise the quality to the enviable M.V. Spares level.

If you need further assistance please feel free to contact us through our website.

Happy and safe Jeep restoring,

Darcy Miller


Often the question of grounding arises when a rear light, particularly Service Stop Lamps, on a vehicle seem to be not bright enough.

The original method of grounding was simply a star washer between the Tail Lamp and the Vehicle Body. These washers were an Internal External Star Lock Washer as seen in the photos below.

The Star Washer is placed between the Tail Lamp body and the vehicle mounting bracket to achieve the best grounding, as the teeth of the Star Washer cuts into both the Tail Lamp and the mounting bracket.

Remember the battery ground (or negative) strap is attached to the frame always near the battery location, on a Jeep at the very front. The body is then attached to the frame by bolts and many vibration insulators which are to some extent also electrical insulators so at the back of the vehicle is where a Tail Lamp grounding problem can occur.

Various parts books call up different washers and it is not my intention to get into the social media frenzy about a simple washer but to tell you what works and what we know and have seen on Jeeps and other vehicles over the past 50 years.

The Willys TM-10-1186 calls up Part Number 53024 “Internal – External Lock Washer between the lamp and bracket for ground” for the MBT Trailer.

The same publication calls up 352760 for the same purpose on the MB Jeep but 352760 is an Internal Star Washer.

We should also consider the original paint on these older Military Vehicles was lead based paint, not necessarily a perfect conductor, however modern paints and primers are by comparison far better insulators so restorations using modern paints need all the grounding help they can get.

In summary put an Internal – External Star Washer over each Tail Lamp stud before fitting the Tail Lamp to the body and tighten firmly to achieve a good grounding.


Happy and safe Jeep restoring,

Darcy Miller


During recent conversations with a major international customer regarding WWII military vehicles, the suggestion was made that we should present the story of M.V. Spares from beginning to current times.

While we have always preferred simply manufacturing and marketing of WWII Jeep parts, we agreed that the story of how M.V. Spares came to be might interest the current generation of WWII military vehicle enthusiasts.

The beginnings of what was to become M.V. Spares started as a hobby around 1970, when I began restoring my first Jeep. The restoration was basically a diversion or side interest from the day-to-day running of the engineering company I had started in 1965.

As the restoration progressed, some parts were becoming difficult to find, so my engineering business, which worked with major automotive manufacturers producing special purpose machinery, also became a de-facto small scale Jeep parts manufacturer. The parts made enabled me to complete my first restoration.

Our first international dealer was a friend and restorer in the UK and M.V. Spares, born from a hobby, began to grow almost of its own volition.

As the manufacturing of the parts grew, along with our reputation of quality, a number of international dealers requested access to the parts to sell to their customers. We even helped some young hopefuls to set up their dealerships.

As we continued manufacturing new parts for the WWII Jeep our brand grew into a well known and trusted quality manufacturer using the technologies and expertise gained while working with automotive manufacturers such as the Borg Warner Corporation, Ford, GM and others.

I must admit, we have never wanted to make every part for a WWII Jeep as such a goal is, in my humble opinion, a fool’s errand. We believe it is best to concentrate on specific parts that we can engineer to the highest standard and design tooling that will continue to accurately reproduce those parts for many years.

From a modest beginning, we have enjoyed a reputation for restoring WWII Jeeps and Harley Davidson Motorcycles for over 50 years, while continuing to manufacture parts for these vehicles.

We have restored WWII Jeeps and Motorcyles for individuals and museums worldwide.

When you have been in business for 50 years, you see major changes, sometimes exciting and appreciated, other times less so. The world has certainly changed over the last five decades. Social media now plays a significant positive role in sharing restoration experiences while sometimes doing exactly the opposite with the expectation of instant satisfaction. One thing restoration projects are not is instantly satisfying!

Following are some photos of our prior restoration facilities and even photo of our old friend, Yasuo Ohtsuka in one the Jeeps we restored for him. Yasuo designed the M.V. Spares logo for us many years ago.

As you can see from the photos, we manufactured our own panels when needed. At the time there were no other panel or body manufacturers available on a commercial basis, unlike today, however the quality and accuracy of current productions is often left wanting.

As our engineering business had extensive design capabilities we did, and still do, produce full design drawings of parts that needed to be manufactured. We also produced body panel drawings.

As we no longer manufacture panels we have made a decision which we hope will benefit the restoration of WWII Jeeps worldwide. We recently upgraded the rear panel drawings to the latest version of full 3D CAD and have decided to release these drawings for free. They can be downloaded from the M.V. Spares web site.

This downloadable file can be provided to any sheet metal shop with laser cutting or other computer-controlled facilities and in a matter of moments they can program their computer driven machine to cut out every component of the rear panel.

The drawings will also be available as a full set of 2D drawings for those who are a little old fashioned and like hard copies.

The downloads will be available by mid-July, 2020.

Manufacturing your own composite rear panel is not all that difficult and many businesses that do laser cutting can do the folding for you for a nominal charge.

The vertical straps shown below are the only part requiring detailed fabrication. If you are restoring your own body you could salvage the vertical straps or, as an easy alternative, Midwest Military, our USA master dealer, have these available.

You can purchase them by clicking here: Rear Body Panel, Short

So, if you’re an individual – make your own rear panel. If you are a club – get your members together and make them for your club. If you are a dealer – then please feel free to use these drawings to make any quantity you require.

Maybe one day we will upgrade more drawings and release them for the hobbyist’s benefit.

We hope you enjoy our pictorial romp through history. It’s been a long journey which we have enjoyed. We will continue to release new high quality accurate parts needed for your restorations and hope you will continue to support us which we greatly appreciate.

We are currently completing three museum quality restorations – a Slat-Grille MB, a ’44 MB and a ’45 MB. We will do some Facebook postings on these vehicles at a later date.

Happy and safe restoring,

Darcy Miller

Choosing a Dimmer Switch

M.V. Spares has just released new Dimmer Switches that are used on WWII Jeeps and other Military Vehicles.

The question is why two different Switches and which one is best suited for my Jeep or Truck?

The main difference between the two switches is the diameter of the stem as there can be two different hole sizes in the floor of the WWII Jeeps.

The switches are installed up through a hole from under the floor.

Early Jeeps, Slat Grilles and early GPW’s generally had a hole in the floor approximately 15/16″ or .09375″ (24 mm) diameter.

Later Jeeps using the Composite Bodies had a hole size of 1-3/32″ or 1.0938″ (35.7 mm).

Our newly released Dimmer Switch 638979 is suited for earlier vehicles with the stem diameter being .875″ (22 mm).

Our newly released Dimmer Switch A-120256 is suited for later vehicles with the stem diameter being 1.031″ (26 mm).

While the earlier smaller diameter 638979 Switch can be used in any vehicle with the larger hole, the A-120256 Switch can’t be fitted to vehicles with the earlier small holes.

If you need further assistance please feel free to contact us through the web site.

Happy and safe restoring,

Darcy Miller

Rear Seat Retaining Springs

These springs are the same for Ford GPW and Willys MB, aren’t they?

No they are not!!

Willys part number: A-2830
Ford GPW: 1161302

Ford did not design the Jeep and manufactured it under license to Willys, they simply copied the Willys drawings and their tooling department did not necessarily follow the Willys shape exactly.

The picture shows two springs clearly marked as to Ford and Willys.

The main difference is in the angle as marked.

To many restorers, this is not significant. But to those who don’t want to mix up parts, we hope this detail will assist.

Happy Jeep Restoring,
Darcy Miller

Radio Connection Box – Conduit

All radio connection boxes and hardware are the same aren’t they ?

No they are not!!

The picture shows two conduits clearly marked as to Ford and Willys.

The Willys conduit has a bend nearer to the end than the Ford conduit and the bends are significantly different in angles and therefore appearance.

All other hardware is the same, just the conduit is different.

I hope this snippet of information is of assistance to anyone restoring a late production Jeep fitted with the Radio Connection Box.

Happy Jeep restoring,
Darcy Miller

Fender Welt Kit

A question that arises regularly is about the Welting material that is used mainly between jeep mudguards and the cowl side panels.

Some restorers believe this Welting should cover the total length of the cowl side panel and encompass all three bolt holes that secure the Mudguard (Fender) to the cowl.

Here is a picture of an original mudguard (Fender) and you will see the Welting does not extend over all three holes.

The original material was a woven heavy cotton saturated in an asphalt bath and therefore can be a good electrical insulator on 6-volt vehicles although its original purpose was as an anti-squeak material where metal to metal contact occurs.

The reason for this Welting being short is to assist in connecting the mudguard electrically to the body proper.

Having restored over 50 WWII Jeeps we have seen this on many original Jeeps, sometimes the welting covers the top two (2) holes and on occasions, we have seen it covering the lower two (2) holes.

The M.V. Spares kit has instructions with the correct lengths, most other kits are incorrect.

Happy Jeep restoring,
Darcy Miller


Identifying Willy’s MB & Ford GPW Lug Nuts

The USA calls them Lug Nuts and other countries call them Wheel Nuts but to all countries, these are a small but critical component of your restoration.

Lug Nuts on the left side of a Jeep are Left-Hand threaded and on the right side are Right-Hand or Standard thread.

There is a significant difference between a Willys MB Lug Nut and a Ford GPW Lug Nut. The MB Lug Nuts are not stamped L or R whereas the GPW Lug Nuts are stamped L & R.

These pictures of original Lug Nuts show the Willys Left-Hand Nut is identified by a small cut in the outer hexagon whereas the Right-Hand Nut has no mark.

Note: the size of the nick seems to vary across the years and this is probably due to different cutting tools.

The GPW Nuts are indeed stamped L or R depending on the thread and have no nick in the outer hexagon.

You will notice on all Lug Nuts the large flat top, typical of the specific manufacturing process for WWII Lug Nuts in that they are all machined from hexagon bar stock.  For those interested in the older manufacturing times these machines were called Bar Auto Lathes, today CNC machining centres.

The material used in machining Lug Nuts is usually of a higher tensile strength than ordinary Mild Steel to allow the nuts to be tightened without distortion and used repeatedly over their expected lifetime.

Some cold headed Lug Nuts do appear as reproductions, their tensile strength is questionable and invariably are indistinct in the GPW L & R stamping and if the MB type are offered they are missing the important identifying nick on the Left-Hand Nuts.

Finally, the subject of finishes, early GPW Nuts have been found as Cadmium plated, we have even seen NOS samples with original tags attached and they were Cadmium plated. Later production was the black Parkerized finish.

Willys MB Nuts appear to always Parkerized finish.

We recommend using original nuts where ever possible and NOS or good used Lug Nuts do appear from time to time.

We will in the near future list a collection of NOS Lug Nuts on www.mvspares.com 

Happy and safe Jeep restoring,
Darcy Miller

Do your rain shields short out?

For a long time, WWII Jeep restorers have called these Rain Shields. Why is a mystery because they never get rained on. The WWII Jeep parts books, Willys, Ford and SNL-G-503 all call them “Cap – Spark Plug Insulator”.

Our customers invariably search for Rain Shields so we also refer to them as a Rain Shields but they are a Cap that goes over the spark plug insulator and not down on the cylinder head to protect from rain.

If you have experienced these shorting out the problem it is not a material problem, its an installation problem. 

Restorers invariably think the Cap must go down to and touch the cylinder head and this is totally wrong.

I am sure you have a copy of TM-9-803 but just in case you don’t here is a copy of one page which shows the rain shield goes as high as possible on the spark plug resistor before the lead is pushed onto the spark plug proper, there should be a considerable gap between the bottom lip of the shield and the cylinder head.

The high voltage in the actual spark plug circuit is likely to be around 20,000 / 30,000 volts and this can skirt across the surface of many non-conductive materials. There are more technical descriptions as to high voltages and its ability to travel over surfaces and jump gaps depending on sharp edges etc but all this is usually more than a Jeep restorer wants to know.

Maybe some can remember children getting car sick and Dad fitting a rubber strap to the car which touched the ground and static electricity was dissipated over the rubber strap and solved the problem, the rubber was not conductive.

So, if you experience this situation make sure the cap is fitted all the way up the copper part of the spark plug resistor and touches the Bakelite part of the insulator.

One final note, we have seen a few early NOS caps with small holes in the top that appear to fit the spark plug and not the insulator. We suspect these are first production and are very rare as we have only seen a couple in the past 40 years. Most NOS Caps we have seen are the larger top holes.

If you have any questions please email darcy@mvspares.com and we will do what we can to assist.

Happy restoring,
Darcy Miller

Fuel Filter Element

Why did we design a Modern element for our Filters?

The purpose of the filter element is to protect the carburettor and fuel pump by removing impurities from the fuel system to allow an engine to work at optimum efficiency.

Today we must contend with “Modern” fuels and these fuels are very different to the fuels of yesteryear; todays fuels can have additives like Ethanol and these additives are less stable today and have water absorbing properties which need to be dealt with by the filter.

Because your Carburettor or Fuel pump design is more than 80 years old you do not need to rely on old technology to protect them.

Everyone understands you can’t use old style diaphragms in your fuel pumps because modern fuels will quickly destroy them so just as it is necessary to change fuel pump parts it is important to use the most modern elements in your fuel filter.

The old-style brass element was designed at a time when modern high efficiency fabric elements were simply unheard of.

The M.V. Spares model MVK-1261 has a micron rating of 10 Micron (10 μm) at 99.8% efficiency. An original brass leaf element has a theoretical rating of approximately 120 microns. This means up to 12 times more impurities will pass through an original style element than an M.V. Spares MVK-1261 element.

Some aftermarket manufacturers have attempted to replicate the original Brass Elements.  The original design is prohibitively expensive and the desire to be price competitive with the modern elements has meant substandard construction where element efficiency is foregone to save on cost.

(Click for larger image)

Using the MVK-1261 you can expect an excellent service life and a corresponding extended service life of your other fuel system components.

Happy Jeep restoring,
Darcy Miller