Just an update,
Spent some time on this machine last weekend cleaning the carburetor,sediment bowl,fuel tank,oil breather and replacing the spark plug.
I know we had spark as there is one hot magneto on the engine with plent of juice coming out.
Probably all for naught as we had a problem getting the Wisconsin AKNS/6.2 hp to fire.
We are fairly certian the rings and/or the valves need replaced as fuel was not rising to the spark plug.
Lack of compression was noted after we removed the drive belts on the mower end and then we could hear air escaping from the crank case breather when we truned the fly wheel by hand.
No compression, no vaccum and then no fuel to the plug.
Not good news.
The Wisonsin engine fellow from Michigan called me back and we talked about the "S" designation on the AKNS engine.
Typically, the "S" designation is for an engine with an electric starter, but this engine does not have an electric starter.
I am fairly certian the engine was painted black originally after looking at the oil breather when clenaing it.
The oil breather's base paint is black under the green.
Also, I went to the Jacobsen site reccomended by bwdbrn1 and scrolled down the list of early Jacobsen power equipment names of mowers and took a hard look at a unit named Heavy Duty Twin 32" and Heavy Duty Twin 32"-2 Speed.
The mower deck measures 32 1/2" wide x 19" deep and there are twin cutter blades under the deck.
I am still unable to find a serial number to see if this name matches up.
So, at this point, I am assuming this mower is a Jacobsen Heavy Duty Twin 32".