The old one was the old sock style so no number. I've brought home 4 different candidate wix filters with no fitment luck yet. This thing is about 4.5 inches tall, mabey 3.5 inches diameter, .55 inch shaft opening.... Anyone have one like it with a number? 1945.
My 1982 fram & Baldwin catalogs only list back to 1948 for the continental engines but they show a C4 or C4F Fram or Baldwin C-41-F.
Under the Oliver tractor section under AG-6, AG-6H it shows a Fram C31, P, PL. all these translate to a Baldwin C-52-MS.
Hope these are helpful.
Scott R.
C4 become wix 51006. 4.74 inches diameter too wide. I called Zimmerman, ended up with a filter that was 8 inches tall, need about 4.5 or so for this canister. I must have a non standard filter attachment. Now the sock style thing I pulled....er...dug out of the housing looked pretty antique so its been there a while. I did find on the alco filter site that I can search by size. Sort of a match found, no conversion to wix or fram. If I do find a match I'll try to remember to update here.
Sorry I was no help, good luck.