Lycoming engine cases can be identified to some degree using the serial number. The 320 series that are equipped with a carburetor will end with a -27. Engines in the 320 family that are built with fuel injection end with -55.
The 360 series engines with carburetors end with -36 and the injected engines end with a -51.
The standard flange engine cases will NOT have any letter following the dash number.
Wide deck engine cases with the standard tappets will have the letter A included following the dash number. Roller tappet cases will have an E suffix. Cases converted to the large body tappets will have a T suffix.
The serial number will not indicate the style of mounting or other configurations but if you call Lycoming with the serial number they will be able to tell you how it was configured and who it was delivered to and when as well as what the engine was intended for.
The first photo is a Wide Deck 320 with a carburetor.
The second an IO360 Narrow Deck
Photo 3 shows the number stamped in by a crank case reconditioning facility.
Number 4 is a narrow deck case without the Alt. mounting pad. The bracket bolts on using the case through bolts on these models.
Number 5 is a wide deck case with an altrnater mounting pad.
Number 6 is a very early accessory housing. The 2 bolts between the fuel pump and prop governor pad are for the early bolt on oil pick up. The later accessory cases don't have these holes machined into them.
The 360 series engines with carburetors end with -36 and the injected engines end with a -51.
The standard flange engine cases will NOT have any letter following the dash number.
Wide deck engine cases with the standard tappets will have the letter A included following the dash number. Roller tappet cases will have an E suffix. Cases converted to the large body tappets will have a T suffix.
The serial number will not indicate the style of mounting or other configurations but if you call Lycoming with the serial number they will be able to tell you how it was configured and who it was delivered to and when as well as what the engine was intended for.
The first photo is a Wide Deck 320 with a carburetor.
The second an IO360 Narrow Deck
Photo 3 shows the number stamped in by a crank case reconditioning facility.
Number 4 is a narrow deck case without the Alt. mounting pad. The bracket bolts on using the case through bolts on these models.
Number 5 is a wide deck case with an altrnater mounting pad.
Number 6 is a very early accessory housing. The 2 bolts between the fuel pump and prop governor pad are for the early bolt on oil pick up. The later accessory cases don't have these holes machined into them.
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