Chainsaw Repair

If I have a tight wrist  pin.  I put the pin in a deep freezer for a day or so.  Never had to do anything else.

Also I never had to put a piston in a 8000 yet either.



 

Regarding tight wrist pins, The aluminum piston will expand much more with a little heat than the wrist pin will shrink in the freezer.

Aluminum expands 3/16" per linear foot from room temperature to it's melting point near 1200 degrees.

The steel wrist pin will expand much less at 1/8" per linear foot from room temperature to its much higher melting point around 2500 degrees. 

Therefore you will get minimal shrinking from placing the wrist pin in the freezer to drop the temperature 40 degrees F.

I heat the piston on these.  Start the pin, position the bearing and get everything ready to go.  Heat the piston crown for 20-30 seconds with a propane torch on low.  Give the pin a shot of oil and in it goes.  Set the clip on the far side of the piston so the pin doesnt push through.

i got new piston and put it in toaster oven at 250 degrees for about an hour pin slipped right in   

i used the domed piston and cyl. kit ,  it was a quick vent saw i bought  off eBay and i put in a new crankshaft  and bearings  and crank seals ,total rebuild i also have a 32" bar for it ,i haven't cut with it yet .I hope it will cut go.od