• 25 Hp Mercury Outboard Manual

The serial number 9137327 for a 20 HP Mercury Outboard is not not listed in the Mercury Marine parts catalog. I don't know about the Yamaha's but the Johnson/Evinrude used to have the serial number stamped into a soft plug in the block too. I need to look at my 2005 115 and see if the numbers on on the engine block somewhere.

When you look on the motor mounting bracket of your Evinrude, you find a metallic, embossed tag with the name 'Evinrude' prominently featured, along with a variety of information on your motor and finally, the motor's serial number. The serial number tells you if the motor was built for the American market, the horsepower, the options it's supposed to have, the length of the driveshaft in the lower unit and what year it was made.

Step 1

Look at the first digit. If it's a letter other than 'J' or 'E,' it's a model variation built for a boat builder to include in a boat 'package.' This also indicates it could be a variation built for a country other than the United States.

Step 2

Audio recording software hardware. Move to the next group of digits a set of two or three numbers that tells you the horsepower.

Step 3

Examine the next group of two or three letters that identify the trim on the basic motor. Some examples are 'FRE' for Four-stroke Remote Electric-start or 'TE' for Tiller, Electric.

Step 4

Shift to the next group, a single letter that appears appended to the trim code. If there are only numbers after the three-letter trim code, your motor has a short driveshaft, likely 15 inches in length. If there is a letter: 'L' represents a 17-inch driveshaft; 'Y' stands for a 19-inch driveshaft; 'X' is a 20-inch driveshaft; and 'Z' is a 22-inch driveshaft.

Step 5

Remember the word 'Introduces.' The next two letters are a simple substitution cipher using that word as its key to identify the year of production. 'I' denotes 1. 'N' equals 2. 'T' stands for 3. 'R' means 4. 'O' stands for 5. 'D' represents 6. 'U' means 7. 'C' stands for 8. 'E' represents 9 and 'S' denotes 0. If that two letter group is 'CE,' it means your motor was built in 1989 since 'C' stands for 8 and 'E' stands for 9.

• Read the last letter, which is used within the factory to designate the model run, of which there are several yearly. For internal auditing only, this letter has no significance to the consumer or mechanic.

• Evinrude Repair Manual -- 2.5 to 250 HP Models, 2001-2009; Seloc Marine

25 Hp Mercury Outboard Manual

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