Motor number decode p15

[OldPly]

P15 motor 23in block ser

number stamped on top of block triangle A7105 it does not match # on frame p15 p15735T08 No surprise. Does "A" mean it a after market motor ? oil filler cap has decal saying fluid drive . its not. wrong cap or different ? motor a lot can happen in 74 years . just wondering what this motor came from . do crate motors have no letter just numbers? (i think i saw that on this site but cannot find it) 

 

 

 

Edited December 6, 2022 by Karey
Add more info

[greg g]

I can't male out the number in the photo, but engine swaps for units out of wrecked cars, rebuilds by dealerships, rebuilds by national chain stores like wards, sears, western auto, Jasper and more were pretty common occurrences.   Without previous owners history, it's a crapshoot. Sometimes there will be a brass data tag riveted to the block.  Many times all that's left is the rivet head and a corner of the tag.  Look in front of the distributor for any evidence of the tag or rivet.  In the cylinder head above #6 cylinder is a threaded plug.  You can remove this plug, insert a 7 inch long piece of stiff wire and measure the stroke by turning the engine over by hand.  The wire will ride the piston so you can find bdc and TDC.  4 3/8 is a 218.  

[tom'sB2B]

This may help you with understanding the engine codes.

https://www.t137.com/registry/help/otherengines/otherengines.php