Whats with these brass filler plugs?

[RegPitt]

I've see at least 3 of these plugs in Mills Bombs over the past several months.
Look just like pipe plugs to me....

 

[millsbomber]

Never seen till today,,,,,,,,, Dave

 

[pointblank0]

Yes. Looks like a radiator valve thingy. Whos grenade is it on?

 

[hicky1300]

I,m with pointblank0. Radiator blleed/drain valve centres.

 

[RegPitt]

Two on 'Gunbroker' have them right now.....

 

[Snufkin]

Two on 'Gunbroker' have them right now.....

http://www.gunbroker.com/Auction/ViewItem.aspx?Item=228193129

Someone just happens to have discovered that some pipe fixtures have the same screw thread as the No.36 filler hole, and in the absence of the correct filler screw, then if the cap fits...

(Some spark plugs also have the same thread as the No.36 filler, but sticking a spark plug in might look too obviously out of place.)

Interesting the body is a Howard and Bullough Ltd (Accrington, England) 1917-18 era casting. The lever is also Howard and Bullough. The base plug is of 1945 Canadian manufacture and doesn't go with the body. The body has what appears to be its original aluminium un-marked centre piece, and there are remains of the centrally applied pink paint band denoting an ammonal or alumatol filling.





Tom.