is there a indication to the engine size on the block, serial #?
6 cyl straight

 

Could be a 300 but very likely a 240.



John

 

Welcome to FTE

The 4th digit of the VIN is the engine code.

While not an absolute after 43 years that the original engine is still in there...

1966: A = 240 1V // B = 300 1V.

The 240 was standard equipment, the 300 was an option.

Very few F100's had the 300 engine.

There are no codes on the engine block that define engine size, because all the 300's were originally cast as 240's.

Only when the block was finished could it be something else.

Measuring the stroke is the EZ way to tell: 240 = 3.18" // 300 = 3.98"

 

If the stroke is longer chances are the deck height is too, any idea what the 2 deck heights are?

 

I haven't a clue...the parts catalogs don't list that info.

 

66 F100. Thanks for the reply. Does the serial number give any indication
to the engine size?

 

John, The metal tag will tell you what left the factory door, not what in in there today.

Get a 7" long white house wire and a Sharpie, poke it in one of the spark plug holes while a friend rotates the engine with a socket on the crank nut. With the Sharpie resting on the manifold let it mark the wire as it passes down & up. Measure the length of the mark and report it back here. We then can tell you what engine you currently have.


John

 

Yes, and I said that in post #3.

VIN aka serial number.

And John...since you have pointed that out before, I also said it was not an absolute after 43 years.