Trying to locate the engine serial number on our daughter’s 1969 F100.

The VIN indicates it is a 240 as does the air cleaner cover (for whatever that’s worth).

We have run into a few issues with parts that suggests the engine has been swapped at some point.

Just want to find the engine serial number to definitively identify the engine. We’ve looked by the starter (which is pretty gunked up, but poking around with a screwdriver has not revealed anything) and under the distributor (no luck). Internet searches seem to vary on where to find the number.

Thanks in advance for the advice!

 

Welcome aboard! Ford did not use engine numbers... Best you can do is check bore/stroke.

 

Thanks. After posting this, I saw a reference to the same thing. Short of rebuilding the engine, we’ll just have to guess what we need. Appreciate it!

 

is the intake manifold cast into the engine, or bolted to the engine?
if bolted, it is either a 240 or a 300. both are the same block. the difference is in stroke and connecting rod length
The stroke is 3.18 for 240, and 3.98 for 300.
if the intake manifold is cast into the block, it is a "small six"
i doubt very much it is a small six though, even with a 250 it will be a slug.

 

Thanks!

If not the original 240, we’re confident it is a 240 or 300. We aren’t rebuilding it, so no way to check stroke.

Thanks again!

 

actually checking stroke is very easy.
get a thin straight rod. like a straightened coat hanger.
remove a spark plug, put the rod in the plug hole and run the piston all the way to the top by turning the crank.
mark the rod. then run it all the way down and mark the rod again.
pull it out and measure distance between the marks.
if it is a hair over 3 inches it is a 240
if it is 4 inches it is a 300

 

Wow! That makes sense. Never thought about that approach. Thanks! We’ll check it out. !

 

65 first year 0f 240/300 engines. You might look on the engine block and intake manifold for a # starting C5, C6, C7 and so on. C being decade of 60's, D being decade of 70's, this might give you an Idea if engine is newer or older than the truck. The first couple years there may have been a wrist pin problem with the 240 engine, they then, went to connecting rods and pistons using a larger wrist pin. Don't know if that applied to the 300 engine.

 

The "small six" (144/170/200/250) were never installed in trucks.

 

By ford.
But I have seen a few swapped in.
Just like I saw a 65 mustang with a 300 in it.

 

Guy on t'other site has an F100 with a 200 I-6. CRAZY!

 

There isn't a serial number on the engine. There will be a casting number, but casting numbers are foundry marks, cannot be cross referenced to Ford part numbers.

 

That is definitely going in my try to remember file! Just goes to show that everything doesn't need to be complicated.