Looking around at various info online I'm guessing this is a 39-41 truck motor but I'd appreciate any help from the many here that know a lot more than me. The guy I got it from said an older gentleman had it in a Model A but after a terminal cancer diagnosis replaced it with a 302 to make it easier for his wife to deal with after he was gone. Also included a pic of the trans that had been behind it in the rod. Curious exactly what that is too, maybe it'll help narrow things down. I'm used to seeing toploaders behind these. Starting to gather parts for a Model A build.
according to the head markings this could help https://www.jalopyjournal.com/forum/threads/81-t-flathead.832146/
Thanks! The bit I had seen suggested the Mercury heads had 81M and trucks 81T. Looks like I need to pop a head. Work is going to be in the way of that for a bit.
Post on the Ford Barn as well as there are lots of folks there that can help. Heads could have been swapped. Plug wire tubes are not stock, as well as the ign coil. Hope you got the crank pulley and cooling fan, as with that single pulley/belt setup, there is no way to run the cooling fan. Also, the oil pans for truck engines typically have a large removable clean-out plate. The “helmet” style distributor shown was used from 32-41, but the “2-bolt” type coil shown was used from 37-41. Again, distributor could have been swapped at any point, so you don’t know for sure.
Unfortunately, when it comes to flatheads, you truly don't ever know until you dig into it. For example, this motor has an earlier intake (appears to be a '36) with a Stromberg carb. Neat replacements, but not original to the motor. My point with this is parts were switched around all the time and you truly never know what you have until you look under the hood per say. Pulling a head will tell you exactly what you have. This motor could be a 24 stud 221 ci, a truck or Merc 239, but you won't know until a head comes off.
It's anywhere from the beginning of 24 studs in 1938 to 1944. The 59 designation that is found on the bellhousing of the post war blocks means it was designed in 1945. Yours is before that.
38-39-40-41-42 p***enger cars had the smaller 3 1/16 bore—-trucks had the larger 3 3/16 bore. 59 style blocks have the raised 59 cast in2 the block and the center water opening in the bottom center of the block is round in shape while the earlier(pre59 but still 24 studs) is more of a t****zoid(exagerrated square) hole in the bottom center of the block. It is nearly impossible to decipher the year with the heads and intake still attached to the engine. Flatheads Forever!!
Pull the heads, measure the bore and post some pics . . . we'll be able to help you. It is definitely an engine between 1938 and 1942 - but that is about all I can tell you at this point. My initial guess is that it is a 221 cubic inch Ford motor - with a 3 1/16 (original) bore.
Can you accurately measure the bore diameter - the tape measure gives us nothing to go on. How about using a pair of dial calipers and finding out whether it is 3 1/16 or 3 3/16. Given the round center water hole, this could be a 39 - 40 Mercury block - which would be a good thing.
Also, 39 - 42 Mercury cars have a 99A engine that was the first p***enger car with a 3 3/16 bore. The rod journals on the Merc cranks were the larger 2.138 diameter and used 99a or 29A full-floating rods. The same size rod journals were used in the future 59x and 49-53 engines. The 221 cubic inch Fords used the smaller 1.999" diameter rod journals and either 91A rods or 21A rods - also full-floaters. The stroke was the same as the Mercs - 3 3/4 inches. These 239 cubic inch engine blocks were highly sought after. Many "urban myths" claimed they were the best block to HotRod, that the nickle content of the cast-iron was different, that they could be bored the most, etc. I've had quite a few of them and they are not thicker and or better than 46 - 48 59x series block. Truth be told the 59x series had a better block (due to valve angle differences). Also, the 41 - 42 Merc style blocks were used in many wartime engines - though usually the wartime engines were factory relieved, and many had dual-sheeve pulleys, special oil-filters, etc.. I've heard that quite a few trucks also used the 239 cubic inch engines.
Here is a picture of a 42 Merc/Wartime block (highly modified) that I built for my 32 Cabriolet. Notice it has the same three center water holes as the block in this post. This one has the "raised intake" mounting surface - which you'll find in many of the 41 - 42 blocks, though usually not in the 39 - 40 blocks. There are also differences in the oil-pan rails (core plugs) - the later 41 - 42 blocks don't have the core plugs, the earlier ones usually do.
Yes! Checked that this morning. I moved a year ago, no clue where the dial calipers are because I'm seemingly never home except to sleep.
Agreed. Dale's work is nothing short of perfection. Looks like you may have wound up with a nice block. Absolutely check it out before investing too much time into it. If you plan to strip it down, once bare, get it mag's AND pressure tested. Before you do, come back and we'll give you tips on how to start the cleaning process at home before you take it the shop.
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