Rolls-Royce 20/25 - install the pistons 



bolt length


The safest method for tightening the big end bolts is to measure the stretched length.  Prior to installation all of the unstressed bolt lengths were noted.

Nominal lengths were 2.210" +/- 0.004"

The nuts were tightened until the castellations lined up with the pin cross-holes.  All bolts were stretched to a length of plus 0.006"-0.008".

fit piston


The piston ring clamp in action.  The cylinder bores, piston sides and clamp were all coated in assembly paste and a thin coat of engine oil.

The assembly paste not only eases the assembly process but will protect the moving parts during the initial  ssssstart-up of the engine.

bottom end


All con rods in place, tightened correctly and fitted with twisted split pins.

It is important to seat the pins so they cannot move.

top end


All pistons and rods on place.  It is beginning to feel like an engine again.