What is the length and the diameter of the crank pin in a 1927 Ford Model T Touring. I want to turn one down on my lathe.
the front pulley pin?
Dennis, go to fastenal and get a roll pin they are same length and hard, if your hole is inlarged that is alright also since they compress when driven in.The new aluminum pulleys all have the roll pins.
#3040 Crankshaft starting pin 3/8" x 2 3/4"
Roll pins are compromise solution, solid pin is what does the work.
Roll pins can work out and cut the front of the oil pan off. They are so hard its just like a tool bit in a lathe. Get a solid pin or make one to fit.
If the rolled pin can work out then you have a VERY worn hole in the crank. After installing two of the aluminum pulleys I don's see anyway they can work out.
I have NOS crank pins if interested firstname.lastname@example.org
If you want the pin to last, get a real pin. A roll pin is not going to be a good long term solution for something that is not a problem in the first place. Get the right part and put it in like Ford did.
I lay the original pin across the open jaws of a vise and take a dull chisel with hammer to the center of the pin. That puts a kink in the pin right in the center. Then re-install the pin which will need to be driven into the front of the crankshaft. It should be a snug fit. Then put the cotter pin in the end of the pin to keep it from coming out.