I'm in the middle of refreshing a '93 Loyale 4wd wagon's engine I recently aquired and noticed that all the pistons have a marking on the top that looks like this: <B> . Does this indicate an oversized piston? Or is it a weight marking?

 

I've been on here researching quite a bit for this rebuild (due to a spun bearing and sludged engine!) This place is a wealth of info and helpful troubleshooting.

 

Thanks,

David

Bump

i believe its for orienting the piston to the block when you are installing the bottom end.

All of Subaru's pistons have A or B sizing within each size. You can order a Standard size unbored piston in an A or B size which is very minimal difference. The block should have markings on it to indicate what the bores need.

Thanks for the replies. I ended up finding a picture of a short block with cleaned pistons that had that "B" marking on them.