FV21N 3/8 drive tool purpose?

[bryanrj]

20200524 240k.jpg (77.68 KiB) Viewed 1890 times

So among the many Snap On items I pick up at local garage and estate sales over the past few years is this FV21N. I get no hits on Google or here in any of the old catalogs on our Snap On site. I am thinking it is a form of drag link or oval head screw drive socket. There is a spring mechanism that allows a shroud to cover the link or screw head. And the base of the driver area is concave, leading me to think in terms of a slotted oval head driver. Nothing spectacular, just curious that no reference comes up when doing a search.

The business end is 0.5" wide and measures .051" thick. Overall height 1-3/4" and 3/4" diameter.

[J.A.F.E.]

It's got the round headed slotted screws called stovebolts on the stovebolt Chevy engines which were the straight 6 engines made from the late 20's to the mid 90's. The early engines used the slotted bolts to hold on the stamped sheet metal parts like the oil pan, valve cover, timing cover and so on and the socket was used to start and hold the bolts. The sockets came in at least two versions.

They show up in the cats as F-21 or F-21-N The link is to the 41 catalog listing.

http://collectingsnapon.com/catalogs/ca ... ogPage=636

[bryanrj]

Thanks for the lead to the 1941 catalog. The F letter makes sense for the ferret sockets listed there. The FN21N must be a more modern build of the socket and may only be found in later catalogs. But it doesn't return a hit on the search engine I was using. I do get a hit on Google search now, but they are hits from the Irish eBay site. Here are the stove bolts in question that the tool is used for.