Have a couple of wrenchs that I can't ID.
The one marked 6151 is 8 inchs long. Has a 9/16 square socket in one end. Has a 15/16 hex socket in other end and a 5/16 cross drilled hole on that end. 6151 is only marking.
The tee is 7 1/2 long and 6 1/2 across handle. Has a 11/16 square socket with 1/2 cross drilled hole. No markings. Any hints on ID appreciated.

The hole in the T is for a bolt so it can not be removed from a valve when you don't want someone walking off with your valve handle.....

No clue on maker tho...

The top one looks like an Economy or Hercules gas engine wrench. Several years ago I did a web page for my website for on these engines. The number on your wrench doesn't match any I found in parts books but it may of been for a different model.

http://www.wrenchingnews.com/hercules/wrench-list.html

Thanks Bus. More careful measurement gives 8 1/4 length. It also has a slight angle on big end. Looks just like bottom wrench in your picture except sides of hex end are full height. With your information will do some more searching on Hercules and Sears engines.