50-53 Mercury Flahead ID

GWRAALSTAD

Junior Member
I'm trying to ID the Mercury flathead that I just purchased. I can't find anything/table that helps me ID the castings #'s on the block. The only markings that I can find are the 1BA markings in the valley of the block. A Vanpelt table says that it might be a 51 Ford, 100HP, passenger car. The engine was pulled out of a panel truck. A rebuild tag on it says 4/10/10. It has EAC heads. this tells me that it was a passenger car block beefed up with EAC heads to put in the panel truck. Any help in IDing this block will be greatly appreciated.
 

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There really are no block casting marks or numbers that can specifically ID your block.
Can you post a photo of the cover that is covering the oil drive gear on the back of the block?
I have found that if it's cast iron it might be a Merc. as Fords were pressed steel.
Also, check the stroke to see if its 4 in. That's what Mercs have. Also post a photo of the water pumps showing motor mounts. Merc were different from Ford. Does it have wide belts or narrow? Dop the external engine components have Merc or Ford part numbers. Do you have a photo of the carburetor? Mercs are different from Ford.
 
I'm trying to ID the Mercury flathead that I just purchased. I can't find anything/table that helps me ID the castings #'s on the block. The only markings that I can find are the 1BA markings in the valley of the block. A Vanpelt table says that it might be a 51 Ford, 100HP, passenger car. The engine was pulled out of a panel truck. A rebuild tag on it says 4/10/10. It has EAC heads. this tells me that it was a passenger car block beefed up with EAC heads to put in the panel truck. Any help in IDing this block will be greatly appreciated.
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I see that the drive gear cover at back of block is cast iron, which as was mentioned, usually came on Mercs.
 
Numbers on the water pumps say they are for Merc's 50 - 53. I hope this is the plate that you were talking about. It is on the back of the block. I'm out of town right now but will be tearing down the block to have it and the heads dipped and magnafluxed. Will see where that goes. I have a beefed up 351w ready to drop in the 31 coupe I'm building but I'm partial to flatheads seeing that's what was in my first car a 54.
 

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Since some of the date code characters stamped on the top surface of the block are rather obscured it's hard to know with certainty but based on what I can see, my best guess is May 16, 1951.
 
I've torn down 1 Mercury flathead, and 6 or 7 Ford flatheads (all 8BA series) in my life and also noticed the Metc had a cast drive gear cover, while the Fords were pressed steel.

Not much of a sample. but with all the other guys......
 
Numbers on the water pumps say they are for Merc's 50 - 53. I hope this is the plate that you were talking about. It is on the back of the block. I'm out of town right now but will be tearing down the block to have it and the heads dipped and magnafluxed. Will see where that goes. I have a beefed up 351w ready to drop in the 31 coupe I'm building but I'm partial to flatheads seeing that's what was in my first car a 54.
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The only time there were "Mercury" flathead blocks was before WW2, and they were still shared with trucks. After WW2 the Ford and Mercury blocks were identical.
Your engine is a great example of parts swapping. At this point it doesn't matter what vehicle the block originally came it, it matters what condition the block is in.
Since you are planning to put the engine in yet a different vehicle, if the block is good what matters next is what parts you bolt onto the block. Pretty much all of the parts that bolt onto the block can be swapped between 1949 through the end of flathead V8 production on both Fords and Mercuries. Some parts look prettier, some parts make it easier to bolt to other transmissions, and some parts make it easier to use simple motor mounts. Don't overthink the engine, put together something that works and be happy.
 
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Ther "1CM" marking on the gear cover plate says it all. I don't think those get swapped out too often. The initial "1" says this part was first used in 1951, but may have been carried over and used in later years as well.
 
Pull a head and make sure its a 4" stroke.


It has EAC heads. this tells me that it was a passenger car block beefed up with EAC heads to put in the panel truck.


If it has a 3 3/4 crank the Merc heads will not "beef up" the engine. In fact it will decrease performance. You need EAB heads to get the most out of the 8ba.
 
There's no doubt that engine is a Mercury. There are many many indications, the heads, the water pumps, the block color, and the "1CM" gear plate mentioned above.
 
Numbers on the water pumps say they are for Merc's 50 - 53. I hope this is the plate that you were talking about. It is on the back of the block. I'm out of town right now but will be tearing down the block to have it and the heads dipped and magnafluxed. Will see where that goes. I have a beefed up 351w ready to drop in the 31 coupe I'm building but I'm partial to flatheads seeing that's what was in my first car a 54.

Everything on the outside points to it being a Merc engine. The blocks and rods are all the same (Ford and Merc), so the most important thing is for the block to be in good shape for a rebuild.

Hopefully it turns out well and you put a FLATHEAD in your car! :D
 
From the pictures it looks like you have a mostly Mercury engine. The cylinder heads and water pumps do not match, the water pumps are 50-51 Mercury and the cylinder heads are 52-53 Mercury. Measuring the stroke will tell you if you have a Mercury crankshaft or not.

For reference, here are pictures of a typical flathead that has had parts swapped around to fit various vehicles or for whatever reason over the years. Parts swapped engines are more common these days than mostly original engines, but may people expect to identify their engines based on exterior parts.

This engine is an 8BA era block, has 49-51 Mercury cylinder heads, 48-52 truck crank pulley and water pumps, 49-53 Ford intake manifold, and a 49-51 Ford passenger car oil pan. It also has a cast rear cover with 1CM markings. It doesn't matter what vehicle this assembly of parts came from, it matters what condition the difficult to find parts are in, in this case they are the block and the Merc crank.

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