Named after its flat cylinder heads, Ford Flathead V-8 engines, developed in 1930 to 1931, were manufactured from 1932 to 1954, and although there were five different Flathead sizes, Mercury vehicles were only equipped with the 239 cubic-inch engine from 1939 to 1948, and the 255 cubic-inch motor from 1949 to 1954. Except for 1946 to 1948, when both brands used the 239, Ford always used the smaller engine size. Identification of Mercury Flatheads requires locating the engine code, which determines the date of manufacture.

• Mercury Serial Number Year Chart
• Mercury Outboard Serial Number Year Chart Canada
• Mercury 25 Hp Serial Number Lookup

The PPT website allows you to search by the Mercruiser Serial Number or Lookup parts by the Mercrusier part number. This ensures you get the correct parts for your specific Sterndrive and Engine. Spark Plug Application Chart ‑ FourStroke Outboard Model Serial # Range Standard Spark Plug Mercury Part Number Standard Spark Plug Manufacturer's No. Suppressor(resistor) Spark Plug Mercury No. Suppressor(resistor) Spark Plug Manufacturer's No. Gap 2.5 FourStroke JPN 0R131842 and up N/A N/A 33-803507 NGK DCPR6E.033. Locate the engine horsepower on the serial number year chart located here to find the beginning serial number for the range that includes your engine. Serial numbers between that year's beginning serial number and the next fall into the same model year. Mercury 2.0 Liter Beginning Serial Number Chart. V-135 121.9 c.i. Mercury outboard engines have a serial number tag that is located on the swivel bracket (port or starboard); or, check the instruction plate, located between the.

Step 1

Locate the engine number. The Flathead's serial number is located on the transmission flange at the rear of the engine block. Look at the top of the bellhousing. From 1938 to 1948, the bellhousing was cast as part of the engine block, and is part of the engine block. The serial number is two to four positions, and may have both letters and numbers. An example, '91A' identifies the motor as a 1931 85-horsepower Flathead.

Mercury Serial Number Year Chart

Step 2

Find the engine serial number on 1949 to 1954 Flatheads. These Flatheads have detachable bellhousings, with the serial number located on a flat surface near the intake manifold gasket face. Look towards the rear of the block on the passenger's side. According to the Flathead Fords and Nostalgia Drag Racing website, the serial number is three to four positions and includes both letters and numbers. Decode the letters according to this key: M=0, G=1, B=2, L=3, A=4, C=5, K=6, H=7, T=8, R=9, S=10, E=11, F=12. The code 'B25L' was manufactured on February 25, 1953.

Step 3

Reference the Flathead serial number to Van Pelt Sales' Early Ford Serial Numbers chart (see Resources). This listing identifies the serial numbers for Ford, Lincoln and Mercury Flathead engines in a year-to-year format.

Differentiate a Mercury Flathead from a Ford Flathead visually. According to Van Pelt Sales, the only visual method of differentiating Mercury and Ford Flatheads is to look at the front counterweght of the crankshaft. Mercury crankshafts have a longer stroke and are identified by a dimple on the top of the crankshaft counterweight.

Tips

• The presence of a 'C' at the beginning of the serial number indicates an engine manufactured in Canada.
• In order to read the serial numbers, it may be necessary to clean the area with a wire brush, rags and cleaning solvent.

Items you will need

• Cleaning solvent, such as de-greaser or brake fluid
• Wire brush
• Rags

Mercury Outboard Serial Number Year Chart Canada

Mercury 25 Hp Serial Number Lookup

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