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VR Filter Question

Posted: Tue May 02, 2017 9:32 pm
by Trip
Does anyone have a photo or two of a VR Filter (?) actually mounted on an M38??

I cannot figure out where it mounts.

Trip (Charles)
51 M38

Posted: Tue May 02, 2017 9:52 pm
by wesk
Not sure what filter you are asking about. The WWII jeeps used add on radio noise filters for their radio jeeps but the M38 & A1 came with a pretty well noise filtered generator/voltage regulator and ignition.

Are you asking about a filter used in a special radio application you are installing in your M38?

Posted: Wed May 03, 2017 5:45 am
by Trip
I bought an M 38 in 1990. at the time I was just flipping Jeeps and had no idea what the history of this Jeep was. It was a true barn find. It took me 6 months to find the engine.The tub was filled with parts due to the vehicle being disassembled for sandblasting. The Jeep speedometer reads 53,000 miles and the Jeep is in great shape. It has been in my warehouse for all these years and I recently decided to restore this Jeep 100% correct.

Back to the "filter". In the parts pile I have is a radio filter. (A small box like piece about 3 x 5 with screw on fittings for an electrical cable on each end. I see these in ads with a companion cable attaching to the distributor. Some articles state it is normally mounted on the firewall under the air filter?

My Jeep seems to have elements of an early M38 and a late M38. Serial number on the dash plate is:36832.(delivery date of 10/51) The engine has an overhaul plate affixed to it showing it was overhauled at "Red River Arsenal" (Texarkana Texas) with an engine number of 5423 and a date of 6/22/55. The boss behind the water pump shows a number of MC 25423.

The Texas title shows the engine number as the serial number. Is this correct or should the title match the dash plate?

I have requested a photo album as I have decided to document the restoration and I have many photos already.

Charles

Posted: Wed May 03, 2017 7:02 am
by 4x4M38
Charles,
It mounts to 10-32 screws sticking out of the firewall below the air cleaner.

Take care,

Posted: Wed May 03, 2017 7:13 am
by 4x4M38
Just to be sure. Are you still 24 volts?

There appear to have been three versions of the firewall. The earliest
had two stamped out pads where the 10-32 screws were below the firewall
where the filter went. See Wes' photo below:

Image

http://www.willysmjeeps.com/v2/modules. ... _photo.php

Yes, before VIN's it was common practice for the motor serial to be put
on a title. You are lucky the rebuild plate has the same number.

Take care,

Posted: Wed May 03, 2017 7:33 am
by 4x4M38
Here is a pic from Wes/ photo album under M38 electrical:

Image


http://willysmjeeps.com/v2/modules/gall ... _lines.jpg

Note is says it was installed on vehicles at the factory through serial MC20599. MC36832 would have not had it installed in the factory, and your firewall should not have provisions for mounting it. Look at your firewall for the two protrusions below the firewall and the four 10-32 screws.

The good news is somebody can probably use it and you can offer it up for barter or trade!

Take care,

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Posted: Wed May 03, 2017 8:55 am
by Trip
Brian,

I have the 24 volt starter, generator, light switch (one plug on back), distributor and wiring harness, although the wiring harness has gotten brittle and will need restoration or replacement. I am wishing to restore the Jeep 100% original and correct. I can see that is going to take some time.

There is no provision (pad or otherwise) for the filter. My firewall is smooth in that area. Actually my firewall appears exactly like the photo of a late M38 as shown in the downloads section of this great website. And since my firewall is in gray primer it looks exactly the same.

Under the dash on the battery box there is the outline of the 3 circuit breakers. Question: Would my M38 have the cb(s) originally.

You guys are awesome.

Charles

Posted: Wed May 03, 2017 11:47 am
by 4x4M38
Circuit breakers were installed on units through 65927.

All of the manuals are available here online free for download,
Including the Ord 9 G740 parts manual. Learn to use it, as it
can answer many questions regarding original equipment and
changes.

Welcome to the party!

Posted: Wed May 03, 2017 11:57 am
by Trip
Brian,

This site is a god send and I have learned so much. There seems to be numerous variations with the M38. For example, my Jeep is missing the lower hinged axe bracket. All of the replacements I see online show brackets with 4 mounting holes. My Jeep body only has 2 holes. It appears your jeep only has 2 also. Where do you get a bracket with 2 holes or do you cut the 4 hole bracket down? Or am I missing something?

Thank you for your responses so far (as I am sure I will have more questions) LOL

Charles

Posted: Wed May 03, 2017 12:05 pm
by 4x4M38
Hi Charles,
I believe the original brackets had four holes, but the M38 only used two.
They are available from our usual suppliers or if you have skill you can
make your own like Bretto did!

Posted: Thu May 04, 2017 10:42 am
by wesk
Hello Charles,

I've been out sick a day or so. Seems Brian has waded in with most of answers from my files to help you out.

He didn't mention a little tool that would answer a lot of your questions a lot quicker.

On out downloads page are volumes of valuable research data. All the manuals you will ever need as well as super info sheets guys like my self contributed to mind bank that gleaned a lot of data from all those volumes of manuals and put it in a simple easy to find spot for you. The M38 data base I put together is one such item. Here's the link but don't cheat. Go to the Downloads Page now and peruse a bit.

http://www.willysmjeeps.com/downloads/M38SNDB.pdf

Once you do that you will have even a greater appreciation for this web site!

I usually mail each new member a survey form. With adequate answers I can usually pinpoint the M38's DOB to within a few months.

Back to your noise filter it was only used on the first 10,599 M38's. That's less then 10% of the fleet so it is no surprise the Army repaired them with the later model and more commonly available distributor since only the very early distributor also used on the first 10,599 M38's had no built in noise filter.
I have requested a photo album as I have decided to document the restoration and I have many photos already.
I did not see a album request there. The last one was April 1st.

Posted: Thu May 04, 2017 6:13 pm
by 4x4M38
Hi Wes,
Am I on the naughty list? I don't see MC11481 on it.

:oops:

Posted: Thu May 04, 2017 7:56 pm
by wesk
That's a very old original of my list. I introduced it primarily for the serial & date cutoffs for changes.

Posted: Thu May 04, 2017 8:38 pm
by 4x4M38
Ahhh.

I have uncovered a few more tidbits while pulling it apart.

I have the form with additions. Would you like them?


And kudos again to you and the other hard working info gurus.
There's no way I would have even known about the filter or three
different firewalls among a thousand other things without the
information posted here.

And Charles, once you have absorbed all of the info in the manuals and
photo pages, wander over here and burn a few more hours learning about
changes the motor pool guys were doing long after the vehicles left the
factory:

http://www.willysmjeeps.com/v2/modules. ... _album.php

Motor pool class is so much more fun than factory!