Tec used a Julian date system, so 05 would indicate 2005 , built on the 307th day in assy line D. Furthermore , a Foreman named Chuck signed off on the build.... Ok, I lied about that part!

@tomplum
Many thanks for determining the manufactured date was November 3rd, 2005.

I still don't know the serial #, is it the 73503C?

Oddly enough Ariens doesn't use the Julian date system to determine manufactured date.

The Ariens ST724E only has one sticker on the machine indicating model # (932141) and serial # (011901).
I contacted Ariens and they told me the unit was manufactured in December 2005. Makes sense since the engine made in November 2005.

What baffles me is how they determined December 2005 from the serial # 011901. There is no 5 in that number, nor any combination of numbers equaling 5.

I would think of the spec # are the final build specs that were ordered by Ariens. The DOM is likely as close to a serial that you get. Don't know about the fine people in Brillion's ID system. I remember a short while back when MTD changed their ID system. so that the date wouldn't be as readily recognized by the consumer. Probably to keep things more copacetic on the sales floor.

Thanks tomplum.
I will be giving the snowblower to my sister so I wanted to have as much information as possible for her.
I have the original owners manual for both the blower and Tecumseh engine.

Ironically, the Ariens owners manual has a place to write in the model # and serial # for both the blower and engine.
Yet the Tecumseh decal does not list a serial #, only SPEC and D.O.M. numbers. Consumer confusion appears to be theor goal.

Leave me add a little to what tomplum said.

05 is the year 2005

307 is the day 307th day of 2005

D is the Mfg. Facility

C is the Assembly line/Shift

0359 is the individual serial # the 359th unit built for that Facility Line/Shift and date.

Here's another tip:
When you go to buy parts for it, just write down all of the numbers, show the list to the sales person, and they will know exactly what the numbers all mean. This way, you will accomplish your goal of buying parts for your machine. And, if you don't know, or have forgotten what the parts is called--the sales person/ counter person will surely be able to figure it out. And, ask the counter/parts person to tell you the age, model, etc. of what you have, so you can impress folks with yer knowlege!

@bok k
Thank you for clarifying that the serial # is part of the D.O.M. number and the serial # is 0359.

Still have no idea why they list a SPEC # but it doesn't matter since I now have the model #'s, manufacture date, and serial numbers.

@rustyj14
Thank you for the tip, I was able to download the parts manual for the Ariens and now have all the numbers recorded should parts be needed for the Tecumseh engine.

I have made up a binder for her that has all the manuals, model and serial numbers, and spec sheets.
Also have 4 extra shear bolts in the binder.
I'm quite a perfectionist when it comes to maintaining and record keeping of equipment.

My sincerest thanks to all for taking the time to answer my questions.