Help with location of oem pistons markings
 

Hi There.
Have stumbled upon a used engine in parts.
What I want to know is if anyone in here have som information to light in this subject, I want to match the pistons and rings in there old cylinders for a perfect seal.
They are marked with a dot on the crown for LH and a line for the RH cylinder bank, also mark with LH/RH inside, but there are also a R3 and R4 pistons marking on each side, can you tel from R3 or R4 we’re they once were cylinder wise?
I men RH cylinder 1 or 3 or LH cylinder 2 or 3 by the R3/R4?

there are left and right pistons due to the strange configuration on top of the pistons. The dot goes toward the front of the engine. This will allow you to at least get them on the correct side of the engine. I cant offer any info on the other info you provided. I can look at my pistons to try and figure it out. Mine are out of the engine now.

Okay the bit with the dot and the dash I have under control the are also marked with RH in the bottom of the piston for dot and LH for dash pistons, but would be really useful if you could check the R3/R4 for each cylinder.

All i can add is all 4 of my pistons has an R3 in them.. I know there is an A size piston and a B size piston. Maybe thats the reason for r3 and r4. B size is slightly smaller by maybe .0015" and i know all of mine are B's. I know this due ro size. Measure yours and see what they measure

A grade

85.985 to 85.995 mm (3.38523 to 3.38562 in.)

B grade

85.975 to 85.985 mm (3.38484 to 3.38523 in.)

My block is a BBBB so should be smaller pistons all over, talked to a buddy of mine and he is pretty sure that the R3/R4 is just a casting number, that tells what series the pistons are made in, so I think I just have to go on and order som new piston rings and hone it and call it a day unfortunately.

From the get go, pictures would have been a help.

Hone and re-ring would be a better bet for a “Perfect seal”.

Weigh the pistons and put like weight opposite.