is this a 6.9 or 7.3?

[GREASE FIRE]

i bought an engine from a church bus and the person who sold it said it was a 6.9, but i just looked at the sticker on the valve cover and it says "7.3 engine family" in one place and then "displacement 7.3 liters" in another.
would this sticker be enough to identify it as a 7.3 or is that sticker on both engines?
there is a casting number close to where the trans bolts up - does anyone know how to tell by it?
thanks,
Paul

 

[GREASE FIRE]

i did some searching and the simplest way to tell that i came up with is to look at the head bolts, and if they are 1/2" then it is a 7.3. Is that correct?
if so the motor i bought which i thought was a 6.9 is actually a 7.3, so i guess that is a good thing.
thanks,
paul

 

[towcat]

get two sockets. both must be 12pt sockets. one 7/16" one 1/2".
if the 7/16 fits, it's a 6.9
if the 1/2 fits, it's a 7.3
simple

 

[icanfixall]

Also look at the stamped in serial numbers on the top drivers side of the block. It will say 6.9 or 7.3 in the serial numbers.