Introduction: Piston Pin Puller

an easy, cheap way to break an old piston pin out to replace the head ( big bore kit users for dirtbikes use this technique a lot)

Step 1:

Step 2:

youll need
                    2 washers (I only have one shown but i wish I used two :-(  )
                    one hexagonally headed threaded rod 1/4" by 3.5-6.5 (depending on the size of piston you have)
                    a nut (the thicker the better)
                    one or two sockets that will allow the threaded rod to pass through
                    a deep well socket to turn the threaded rod

                    for really badly stuck ones you may need vicegrips/pliers

Step 3:

put the rod through the hole in the piston ring, making sure the head is in contact with the rings surface

put a socket (with the more open end) facing towards the piston pin, being sure that the opening is large enough to fit the pin inside

put two washers on the other side of the socket

and lastly put the nut on the threaded rod

Step 4:

use the deep well socket fitted to the threaded rod to tighten and extract the piston pin

if the rod starts spinning, switch to vicegrips on the nut and use vicegrips to keep the rod from spinning

if all fails, use a heat gun to get the head hot and expanding

Comments

author
jcolee (author)2014-03-19

Great write up, I actually made this to pull some piston pins from an old 305 Scrambler motor that had been sitting for a while. Sadly, one of the piston pins was REALLY stuck and ended up bending the rod and squashing the washer. I ended up having to hit it with a hammer in a vice.