Driveshaft housing

Bigsweet75

Junior Member
Good afternoon,

I was under my 1931 Briggs Fordoor model A
and noticed an opening on the driveshaft housing
that looks like needs some type of cover plate.
Can anyone tell me if there needs to be a cover there
and what the name of it is?
 

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You need a speedometer drive housing bolted to this opening. My guess, you don't have a working speedometer.
 
Ah ha I learned something new today. Speedometer drive housing goes there!
Truthfully, I have personally never driven this Model A nor any Model A. I started working on restoring this one 7-8 years ago and hit a wall in my efforts a few years ago. I finally started back at it a month ago and I am trying to inventory everything to see what I need to get her running. Long story short I need a speedometer amongst other things. Thank you for your help!
 
I believe I just came across the speedometer/odometer? Also, does anybody know how to tell which speedometer drive housing fits my 1931 car? Mikes Affordable A’s parts has two different ones listed for 1931.
 

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That speedometer (oval) was used until about July 1930. At that time the speedometer was changed to round. If your dash plate opening requires an oval speedometer either the fuel tank has been changed or the car is not a 1931.
To get the correct speedometer drive housing and gear you must determine the differential gear ratio. Most passenger cars of this year were 3:78 to 1 ratio.
One way to determine the ratio is:
Remove the spark plugs to make turning the engine easier.
Place a mark on the crankshaft pulley and a corresponding mark to check revolutions.
Place the transmission in 3rd gear.
Place a mark on the bottom of the right front tire at the floor.
Using the right front tire, pull the car forward observing and counting the engine turns until the tire mark is on the floor.
If the turns are just over 3 1/2 it is a 3:54 to 1
If it is close to 3 3/4 turns it is a 3:78 to 1
If over 4 turns it is a 4:11 to one.
Vendors sell the proper Adapter for the correct ratio.
 
The oval speedometer came with the car car in a box of parts when I purchased it from someone in 2015. I think some of the parts that came with the car were extras they picked up at swap meets back in the 80s. I’m pretty sure my body is a 1931 Briggs Model A Fordoor. It appeared all original with original wood on the underside of body.

Thank you kindly for the procedure on how to get correct speedometer Drive housing.
 
"with original wood on the underside of body."
Are you speaking of wood blocks or other wood like sills?
Is this a Slant Windshield car?
 
No this is not a slant windshield body it is a Briggs Fordor. The underside of the Body is "wood sills". The body had the original wood sills and black paint. I bought it from previous owner who had purchased all new "wood sills" but hadn't replaced(or installed) it.

I also noticed in a box of parts that came with the Briggs an instrument panel that fits the oval speedometer. Could the Briggs 1931 body have an oval speedometer?
 
"Could the Briggs 1931 body have an oval speedometer?" No.
Only if it has a '30 fuel tank.
If the instrument panel will fit the fuel tank it is a early '30 tank.
Oval and Round instrument panels will not interchange.
 
No this is not a slant windshield body it is a Briggs Fordor. The underside of the Body is "wood sills". The body had the original wood sills and black paint. I bought it from previous owner who had purchased all new "wood sills" but hadn't replaced(or installed) it.

I also noticed in a box of parts that came with the Briggs an instrument panel that fits the oval speedometer. Could the Briggs 1931 body have an oval speedometer?
I was not aware that there were any 1931 non-slant Briggs Fordors. My understanding is that the 4-door sedans began transitioning to the slant design somewhere around November 1930 for both Briggs and Murray. So yes, there could be some 1930 cars with slant, but not 1931 cars with straight windshields (all, please feel free to correct me, the memory isn't what it used to be). I think the oval speedos were used in the 1930 models until somewhere around June 1930. My early 1930 Town Sedan has an oval speedo, my 1931 slant Town Sedan has a round speedo. The only way to get a close date your car is to see what the frame number is, which may or may not be the engine number or the number on the title. Another clue may be whether you have a two-piece or one-piece splash apron, that transition was also made in late 1930. Relying upon the difference between 1930 and 1931 radiator shell is the weakest link, lots of swaps were made over the years.

And the cables and housing are dependent upon which speedo (oval vs. round) actually fits your car. If you find the instrument panel and it fits the speedo, and both fit on the tank, that would be a big help.

As far as which of the late 1930-1931 housings available from Mikes is the right one - one is for standard differential (3.79) and one is for high speed (3.54) differential. Unless you determine otherwise, standard is probably what you need. See MAG's post above to figure out which you have. Most Model As have the standard differential.

JayJay
 
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Here a couple of pictures when I first got the Briggs Model A. There is an original dealer sticker on the drivers side calling the body a 1931. Can you look at the gas tank and tell which year it may be?
 

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They did have both straight and slant window fordors in'31. It has a '30 radiator shell if that means anything. But that could easily be changed out.
 
I can't tell the year of the gas tank by looking at the picture. Perhaps someone else can.

"instrument panel that fits the oval speedometer."
Try to put the instrument panel on the gas tank. If it fits it is an early '30 tank. If it doesn't fit it is a late '30/'31 tank.

Looking at the splash apron on picture #2 (right side) appears to be a splash apron which includes the running board. These splash aprons were found on the early "30 cars and phased out in late '30 and the running board was not part of the splash apron as JayJay states. The nose piece of the splash apron was spot welded to the front fender. These splash aprons were not installed on '31 bodies. The later single piece splash apron included the nose piece and was bolted to the front fender.
 
The body may be too far disassembled to tell, but if there is a small lamp in the body crosspiece that is inside the cowl and above the instrument panel, then that's the dash light and is associated with the round speedos. Oval speedo instrument panels had the dash light on the panel itself.

And pretty obvious, the (not indented) firewall shows that it's an early '31 at the latest.

JayJay
 
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