EarlyCJ5.com Technical Library

A technical library for classic Jeeps

Buick V6 Casting Numbers, Internal Specs For Most Years and Notes


Compiled by Joel Vande Berg

Year CID Liter Bore Stroke Description Block Casting Crank Forging Head Casting
1982 231 3.8 3.80 3.40 V6, Even-Fire, Turbo Charged, Crank may have 5/8" or 3/4" Pulley Bolt Hole 25506818 1260877






25514290

1981-79 231 3.8 3.80 3.40 V6, Even-Fire, Turbo Charged, Crank may have 5/8" or 3/4" Pulley Bolt Hole 25506818 1260877 25506293






25506397
25504443
1978 231 3.8 3.80 3.40 V6, Even-Fire, Turbo Charged, Crank may have 5/8" or 3/4" Pulley Bolt Hole 1254083 1260877 1257051






1261438 1257125 1257722







1255674
1981-79 231 3.8 3.80 3.40 V6, Even-Fire, Crank may have 5/8" or 3/4" Pulley Bolt Hole 25506818 1260877 25506293






25506397 1257125 25504443






25505554 1255674 1262098






25514290
1261377






1261787

1978-77 231 3.8 3.80 3.40 V6, Even-Fire, Split Rod Pin Crank, Even Fire Engine 1254083 1257125 1257051






1255862 1260877 1257661






1261438 1255674 1257722
1977 231 3.8 3.80 3.40 V6, Even-Fire, Straight Rod Pin Crank, Odd Fire Engine w/ Integrated Dist. Drive 1254083 1255645 1257051






1255862 1255846 1257661






1261438 1357898 1257722







1378354
1976-75 231 3.8 3.80 3.40 V6, Odd-Fire, Straight Rod Pin Crank, Odd Fire Engine w/ Non-Integrated Dist. Drive 1249432 1357898 1249175







1378351 1254164







1378354
1967-74 225 3.7 3.75 3.40 V6, Odd-Fire, Kaiser Jeep Corp/AMC 1358435 1357898 1358676






1396736
1368767






1381623
B-1376348






1375162







991503

1963-6 225 3.7 3.75 3.40 V6, Odd-Fire, FWD/RWD w/ one barrel Carb 1396736 1327898 1358767
1963-65(? 225 3.7 3.75 3.40 V6, Odd-Fire, FWD/RWD w/ one barrel carb 1358435    
1961-63 198 3.2 3.625 3.20 V6, Odd-Fire, FWD/RWD Buick applications only 1349430

The remainder of this reference is written and compiled by Jamie Carter and maintained by the Early CJ-5 Page.

225 Intake casting numbers:

- there may be others...

225 V-6 engine id codes: Buick special 64-67 (1 and 2 bbl.)

...so the codes are either on the side or front of the block just under the cylinder head.

(I have heard rumors of a few engines produced in '63).

All are listed as 9.0-1 comp. ratio.

The engine codes seem to indicate that the first letter is the engine year, while the second letter is the comp ratio (9.0-1). The two letters together identify this engine as a 225 V-6, as the same year letter was used by Buick for all engine types '64-'71 (v-6, v-8) but the second comp ratio code letter varied between different engine types with the same comp ratio (i.e., a '64 V-6 comp ratio 9.0-1 is a "KH", while a '64 300 V-8 comp ratio 9.0-1 is a "KL").

Buick V6 Number Locations

The front of the engine is to the right, the block casting # is on the rear, the engine # is on the right bank.

Thanks to Joel Vanguard for the picture of V6 number locations

From "Service Manual Jeep Universal Series";

"The engine code number shown in Fig A-4 is provided to identify the Dauntless V6-225 engine. The meaning of the coded letters and numbers that are stamped on the right front face of the crankcase, just below the rocker arm cover, between exhaust manifold ports, is given below:

Letter to designate market:

Letter to designate year Built:

Letter to designate Engine Compression Ratio:

The next three numbers are then the day of the year noted in the second position.

In 1965, some Jeep V-6's are listed as coded "KLH" (and maybe'64 or '66 engines as well, still trying to research this).

All Buick 231 block casting numbers from my info begin with the numbers 124, 125, 126, or 255.

(last update 12-Apr-04). Information from various sources named and unnamed, some personal opinions are expressed. Not responsible for errors, as the weeding of the garden of knowledge to find the flower of truth is a never-ending quest.

jdc. & ahs.