that 'rattle' was a
dying bottom end
Join Date: Jun 2009
Location: United Kingdom
lower compression on cylinder 3 could be down to a valve or a ring, if you do a wet test it will give you more of an indication. You should get slightly higher readings with a wet test, but if they don't improve much then its potentially a valve issue.
Edit: just incase a search hero has a fail moment (despite how funny the consequences would be) - wet indicates a small amount of oil in the cylinder, not water!