Identification of Buick V6 Engine

[john s]

I am trying to identify the type of Buick engine that is in a Willy's Jeep
I inherited. The distributor is on the right front of the engine. The
valve covers are blue. One has a number "149" imbedded in the metal.
The cylinder numbers are 1-3-5 on the right side, and 2-4-6 on the left, clearly marked. I have been unable to find the engine identification numbers. I think it's a 225 or 231 but have not idea if it's odd or even firing, or the year. I think it was installed in the mid to late 60's. Any input on this
would be appreciated.

[bob k. mando]

The cylinder numbers are 1-3-5 on the right side, and 2-4-6 on the left

i think that you are looking at the engine while standing at the front bumper. please keep in mind that standard descriptions for the engines are referenced to the car, not the observer. as for instance, it's normal GM procedure to have the odd numbered cylinder bank on the left or drivers side.

just use 'drivers' or 'passenger' side to describe it and there can't be any confusion.

The distributor is on the right front of the engine.

for instance, a Buick engine has the distributor mounted at the front and tilted to the left or drivers side.

I have been unable to find the engine identification numbers.

the head casting #'s will be under the valve covers. pull one and look for a 7 digit #.

I think it's a 225 or 231 but have not idea if it's odd or even firing, or the year. I think it was installed in the mid to late 60's.

the switch from odd to even fire was a mid-year change over in 1977. all 231's from 78 and newer are even. the odd fire 231 is a very rare animal as it only saw production from 1976 to mid year 1977.

all 225's are odd fire and production ran from 1963-67.

there was no 'Buick' designed and built v6 from 1968-76 but Jeep had bought the tooling and design from GM and i'm not sure about their production years or numbers.

[john s]

Thank you very much for the info you provided on Buick/GM engines. My father installed the Buick V6 in the mid to late 60s, to the best of my knowledge. The Jeep has been sitting dormant for over a decade, and I
am going to get it running one way or another. I soon realized I need to
figure out exactly what's under the hood.

You are absolutely right - I was describing the position of the pistons and distributor standing at the front bumper. Your comments about the distributor, etc. make me think it's a 225, with odd firing. The distributor is not only on the driver's side - but it it tilted. I realize I did not provide a whole lot of info for someone to answer my question. In the next couple of weeks, I will take a look for the engine number by the valves as you suggested. Again, your reply is appreciated.

[KrisW]

The 225 is the most common, but there was also a 198 v6 produced in the early 60's. If it's factory Jeep then its a 225. If it's a transplant from the 60's then all bets are off.

It is Buick, though, so at least you have that going for you!

[bob k. mando]

there was also a 198 v6 produced in the early 60's

good point. the 198 was in production in 1962 and 1963 only.

the 198 has a stroke of 3.200" while the 225 and 231 are 3.400". you can pull a spark plug a use a wire to find the BDC to TDC distance.

[john s]

Recently, I received some real good feedback in regard to a Buick V6 engine I
am trying to identify, which is in a 1948 Willy's Jeep. Thanks to your
feedback I looked under the valve cover and found the head casting
number 25506293. I believe the number is that of a 1980 or 1981 Buick 3.8 liter V-6 engine (originally I thought the engine was much olderl).

Apparently, the same head casting number is on 80 and 81 Buick v6 3.8 liter engines - unless I goofed. What I am curious about is the letters "CFD" to the left and below the head casting number. Also, to the right of CFD, was the number 45. And there was a "7" in the upper left. The question I have is how can you tell a 1980 from a 1981 - maybe the additional numbers will do it for an expert in this area, and maybe not. Your input will be appreciated. Thank you.