What year is this Mercury Flathead???

MyDads37

MyDads37

Junior Member
I have a Mercury flathead that I would like to know the year.
I've searched for clues on the web that pointed to the back passenger side of the intake that would have the "date stamp"... mine has 2 A L stamped on it that I can't seem to find a reference to... the only other clue is the D25 2 EAC on the heads.
Any info is greatly appreciated!
 
MyDads37 said:
I have a Mercury flathead that I would like to know the year.
I've searched for clues on the web that pointed to the back passenger side of the intake that would have the "date stamp"... mine has 2 A L stamped on it that I can't seem to find a reference to... the only other clue is the D25 2 EAC on the heads.
Any info is greatly appreciated!
Click to expand...

The heads date of manufacture is April, 25th 1952 Mercury.
 
EAC are Ford heads. '52-'53 Mercury would have raised letters "ECM" and Mercury logo at the bottom.
 
52 Mercury
DSCN0211_zps9442217b.jpg
 
FoMoCo had some strange prefixes in 1952 an 53. They were transitioning to the new system where B became the designator for the 10 year period from 1950 to 1959 the the follow on characters represented the year of introduction and series of vehicle types that the parts were originally designed for . In 52 & 53 they used prefixes like FAA and the E groupings that gave no sense of what the parts were made for or what year they were introduced for other than the fact that those "in the know" know when they were made. The 1CM prefix on heads made for the 51 Mercury (Merc-O-Matic) as replacements for the 8CM heads. The EAC heads were a slight redesign for compression ratio (CR) but not by much. The EAB heads for the Ford vehicles were the highest CR of the stock heads for the 8BA family of engines. The only ones with more CR were the Denver Heads made in the early 50s.
 
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EAC heads were the same CR on the Merc stroke as EAB heads were on the Ford, at about 7.2 to 1, among the highest, not the lowest CR , except apparently in San Antonio? ..B.
 
Barlea said:
EAC heads were the same CR on the Merc stroke as EAB heads were on the Ford, at about 7.2 to 1, among the highest, not the lowest CR , except apparently in San Antonio? ..B.
Click to expand...

Yep the EAB heads were some of the highest compression heads. They had less volume than the EAC heads, the reason they "look" the same compression wise is that the EAC heads were on a bigger engine, thus equal ratios.
"Denver" heads were higher. And I believe some Canadian heads.
Sorry bud, all your pic shows id wise is that it's got Merc heads on it.
The only real way to tell if he's a Merc, is to measure the stroke.
plenty of pretend Merc engines out there.
Martin.
 
I got my wires crossed on the CRs. It happens when you're watching kids blow off firecrackers while trying to type.

If they transposed the figures 2AL to A2L then it would figure to be a block made in 1953. The stamper might have had a brain fart like I did. It could still have a 3 3/4" stroke though. The only way to tell is to measure it or look at the crankshaft for signs of being a 4-inch stroke like the wide cheeks or sometimes the size of the journal clean out plugs.
 
Tugging a head and measure is the easiest way I think on a complete engine.
Mr wrench, I knew it was a brain fart mate, happens to us all.
Martin.
 
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