ok, what could cause this
compression test's
cyl. 1= 140
cyl. 2= 175
cyl. 3= 46
cyl. 4= 180

ok, i am guessing that i have a blown piston ring in cyl. 3, but what would cause cylinder 1 & 2 to be low? How can i fix this, i plan on putting new rings on soon, will this fix it?

optimum compresson is 180.