What the heck is this? It looks to be a place for a dipstick or something, but there's already a place for that further back. Should I leave it? Or should I plug it? I have a roll pin and bolt that will work with a coupla washers and some creative cheating.

Thanks again for your help

That looks like the hole for the dip stick tube for a front sump pan, used in sedans. Trucks and Tbird used a rear sump pan and the hole was further back on the block.

Get a plug from a parts store.

54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

That is the front sump dip stick hole. Plug it with a 1/2" expansion plug (like a mini frost plug) available at parts or hardware stores. Its not an exact fit so start it in a piece of steel with a 1/2" hole to size it better. Use a hardwood dowel to drive it in and try and keep it straight. Use a little thread sealer and you will be good to go.

Mark

1956 Mercury M100
1955 Ford Fairlane Club Sedan
Delta, British Columbia

The proper size should be .540" Napa should have them. SEP 3812098


Lawrenceville, GA

I just measured my 312 and its 1/2 right on.i have never bought one as both holes are the same size.if I need to change it I drive it out and put in the other hole.