just about finished my rebuild of my sapp cos engine, what kind of oil do people recomend for the running in, as i read somewhere it should not be synthetic, cheers

 

use some cheap thick oil to run it in with

 

mineral oil

 

Can some explain why, other than cost.

Cheers
John

 

it needs to allow the bores/piston rings to bed in against each other ,if superior quality oil was used, this wouldn not happen because it would keep the friction between them too low. a cheap thin running in oil will allow this thus reliving any stress raisers or high spots . this is why it is important not to overrevv the engine during this time as you may be running metal against metal at some points until it has doen it work

 

Running in oil is very messy and tiring

 

do dum tis!