Technical My first "what is it ?" Post !

I picked this up today and thought it was cool but got no idea what it is.

As you crank the thing the end spins to the right 3/4 turn and then reverses and goes back a 1/4 turn then reverses direction again another 3/4 turn over and over again.

Thought maybe something for lapping valves, maybe a suction cup on the valve then this thing has a blade/key on the end that turns and maybe this thing sticks into a slot on the suction cup maybe...

There are no markings, numbers, or anything else on it.

So any ideas ?

...

 

Sounds like tapping threads process, but tool doesn't look it.

 

Valve lapping tool. Some old valves had 2 holes in them. The end comes off to switch to a suction cup for others.

Dave

 

yup, you had it figured out and didn't even know it.

this engine has slots on a few of the valves....1941 Cad 346

 

Thanks guys !

Nice to know this Ole brain can still muster some power to figure things out after all !!

@squirrel thank you for the visual ! I totally understand how the blade work now !

I will admit the only thing that made me think valve lapping was the fact that it auto reverses then back to normal direction.

..