freeze/frost plugs

[sim60]

Hi, i was wondering if anybody could tell me the size of the frost/freeze plugs(we call them core plugs over here) on a 1952 m37 as one of mine has gone rotten,it`s the one behind the oil filler tube(they all look the same size on that side of the engine).I have tried measuring with a tape but it`s not that accurate,getting plugs is not the problem as long as i know the size.Hardly anybody over here stocks bits for an M37 unless you can tell them it`s the same as a wc??.
Thanks in advance Simon

[MSeriesRebuild]

Diameter is 1.625". The better option is brass plugs as they will not rust out like steel plugs do. They are the convex or more commonly known as the "saucer type."

[sim60]

Thanks for the reply i will try to locate some over here my usual stockist has not got any.
Thanks Simon

[PoW]

Yep, same on all the old flatheads, WC included.

Best to go with all brass, and do them all.

Don't forget the one in back, hidden by the bell housing. Some heads have one, too.

Not a afternoon job, but better done now than having a breakdown later.

DG