TheSamba.com :: View topic

Thu Nov 22, 2012 10:15 am

Next, the rear mounting bracket is installed onto the back of the radio.

Mount the radio in the car. The top of the mounting bracket bolts onto the windshield washer motor.

Thu Nov 22, 2012 10:16 am

Inside the cabin, we can mount the chrome “Big M” faceplate with two chrome screws.

According to the installation instructions mentioned earlier, two washers are placed under the faceplate as seen below.

Then, the knobs are placed on the shafts.

Thu Nov 22, 2012 10:16 am

If we look at page 2 of the Motorola installation manual…

At the bottom of the page, we see the wiring installation which recommends getting power directly from the ignition switch. These instructions are for the 6M radio. It’s possible this would be correct power source for the 5M and the 6M radios.

The original ignition switch from my ‘57:

The back of the switch:

The green arrow points to terminal “15” (it’s a little hard to see the number to the left of the terminal). It looks like the installation manual wants the radio to receive power from here.

However, my radio was wired as shown below…to the fuse block.

Here’s my original 4-fuse box from my car:

if we remove the red (16 amp, i think) fuse, the original paper fuse box insert can be seen. The green arrow points to “radio”.

Thu Nov 22, 2012 10:17 am

Next, connect the speaker wires to the speaker.

The ends of the speaker wire are shown below:

The terminal ends are 1/8” in diameter by ½” long.

The discs are 5/16” in diameter by .075” thick. I can’t identify the material…maybe cardboard? Pressed paper? Anyway, notice one is natural brown in color and the other is black.

Thu Nov 22, 2012 10:18 am

Attach the antenna wire to the radio as seen below.

The Motorola sales brochure doesn’t mention if an antenna was included with the kit. So, I’m not sure what would be “correct” for our oval beetles…the single-mount or dual-mount antenna. My ’57 came with a dual-mount.

Here’s what the Bentley manual says:

Just for reference, here’s the rest of the Bentley manual’s radio section:

The antenna mounts onto one of the front quarter panels of the car. It was up to the dealer/installer to locate and drill the holes in the car.

For reference, here is where mine was installed.

A view from the side:

I drew some lines with a magic marker:

The distance from the top edge of the quarter panel to the center of the bottom hole is 10 3/8”.

From the top edge of the quarter panel to the center of the top hole is 4 1/16”.

The distance between the holes as (center-to-center) as shown below is 5 3/8”.

The distance from the flange to the center of the top hole is 3 5/8”.

The distance from the flange to the center of the bottom hole is 4 3/16”.

The diameter of the holes is 9/16”.

Thu Nov 22, 2012 10:19 am

Well, that’s all i have…

Rock out…

That’s my rhyme…

Take it the streets, bee-otch. (butthole surfers reference)

Thu Nov 22, 2012 11:54 am

Great write up. Incredible fabrication skills! Love your attention to detail (the stamps..... :shock: :D !) =D>!

Great to see the VWA8 brochure. I have one in my 60 vert and had a mp3 connector added. Here it is:

Thu Nov 22, 2012 1:30 pm

=D> =D> =D> =D>

nice detailed thread on Big M's!!!! one of my friends has a "5M" radio. what year would it be from? it came out of a 56 bug. so would it be a 56?

Thu Nov 22, 2012 1:41 pm

OvalinAz wrote: one of my friends has a "5M" radio. what year would it be from? it came out of a 56 bug. so would it be a 56?
Yes. It's from '55/56. See here
http://www.radiomuseum.org/r/motorola_5m_5_m.html

Fri Nov 23, 2012 3:26 am

OvalinAz wrote: one of my friends has a "5M" radio. what year would it be from? it came out of a 56 bug. so would it be a 56?

no, it's not from 1956. if you reread the 4th post, the model number designates the model year. so, a 5M radio was manufactured for the 1955 model year.

it would have been available from late 1954 through 1955.

if your friend's car is an early '56, then the dealer could have installed this radio as it may have been sitting on the shelf.

otherwise, the 6M radios should have been available for the "new" 1956 beetles.

at any rate, the 5M would be just fine for your friend's '56. if he had an 8M radio installed, for example, it would be wrong. the radio didn't exist yet (remember, the 8M radio was manufactured for the 1958 model year).

Fri Nov 23, 2012 6:47 am

8M doesn't necessarily have to be considered wrong for a 56. Due to the high cost of this upgrade, many people returned to the dealership to have a radio installed after purchase.

Tue Apr 16, 2013 1:53 pm

mark_85226 wrote: 8M doesn't necessarily have to be considered wrong for a 56. Due to the high cost of this upgrade, many people returned to the dealership to have a radio installed after purchase.

agreed...this is another possibility.

Tue Apr 16, 2013 2:01 pm

i have been contacted more than once in regards to the bracket at the back of the radio that bolts onto the wiper motor:

i noticed there are several "big m" radios in the classifieds every so often and they all seem to be missing this bracket.

i created an engineering drawing from my original so it can be duplicated if an original can't be found.

the drawing is located in the archives:

http://www.thesamba.com/vw/archives/manuals/motorola_bracket.php

Tue Apr 16, 2013 2:08 pm

on another note, this speaker grill popped up in the classifieds recently:

it still has the original gasket:

i mentioned earlier that i didn't have a picture of the gasket on my speaker grill...the photo above shows it quite well.

again, i'm not sure if this gasket would have come with the radio "kit" or if the dealer put something on from an available extrusion.

there doesn't appear to be a seam on the gasket. so, maybe it came with the kit???

Fri May 24, 2013 11:32 am

This was an absolute fantastic thread. I have always wondered why my oval's radio, a sapphire I, didnt look right in my face plate. Now I know why. I have the faceplate in this bottom picture

Im sure the original Motorola played out and they grabbed a Bendix. Im sure this particular radio will be tough to find.

Fri May 24, 2013 1:38 pm

Best thread I've read in a long time, amazing work!!! Thanks so much for sharing...

Sat Jan 18, 2014 5:26 pm

I came across this incredible topic looking up info on this cruddy old radio I found. Turns out it's a Motorola 8M! :D I remembered I had this kit sitting out in a drawer in my toolbox for some time. I don't know if the pictures are useful at all as a reference as the work done here has been incredible. But it does answer the question about the speaker plate seal! It's indeed part of the kit.

As you can see it's for a 6M radio, but I don't see much difference between that and an 8M, do you think it'll work? Thank you Flyertim for this fantastic topic!

Tue Jan 21, 2014 6:43 pm

Nice graphics and great documentation

Tue Jan 21, 2014 7:08 pm

Tue Jan 21, 2014 8:57 pm

flyertim wrote: i have been contacted more than once in regards to the bracket at the back of the radio that bolts onto the wiper motor:

i noticed there are several "big m" radios in the classifieds every so often and they all seem to be missing this bracket.

i created an engineering drawing from my original so it can be duplicated if an original can't be found.

the drawing is located in the archives:

http://www.thesamba.com/vw/archives/manuals/motorola_bracket.php

A spectacular post, Tim. One of the most detailed and informative ones I have ever seen concerning these older Motorola Volumatic vacuum tube radios intended for installation in the 1953 thru 1957 sedans.

One note with regard to the detailed drawing you had created of the rear mounting bracket for these radios. The finish from the factory was bright zinc plated. Anyone who wishes to fabricate one of these mounting brackets and make an exact duplicate to the original dimensions and finish will require this information.

You may wish to revise this drawing to include the information pertaining to the finish.

Thanks for all of the time you have invested in this topic.

Bruce