The V8 Owners Forum -

I bought a 3.9 serp motor supposed ,( yeah ,I know )to have been serviced by a reputable firm and only have 120,000 km. Everything was fine till I got the heads off and then I find pistons fitted backwards , some at least are [attachment=0]IMG_20200111_174531.jpg[
Do these pistons get chucked in any old how or are some of these in back to front?
These two pistons are side by side ......one surely had to be arse about face ?

This piston looks like a bit of (exhaust ,) valve contact , and the bearing shell looks a bit suss ( only one. I have removed so far )

Putting pistons in facing backwards is usually the result of someone failing to remember that Rover rods have dimples on them which for each pair of pistons have to face each other. So they fit all the pistons onto the rods the same way. Result is 50% of the pistons are on the wrong way. Not the worst thing that can happen.

Valve contact is most likely someone over-revving it, unless its got some monster cam in there.

Yeah your right . If I were to turn one piston out of every pair round 1/2 a turn they would all line up ......actually I bet every 2nd rod is in back to front. Supposed to be an unmolested motor but unless rover stick their sumps on with roofing silicon and no gasket someone's been in there and put all the dimples facing the same way upon reassembly. I can't see someone removing pistons from rods and then refitting them (wrong way round ) , poop of a job, all that pressing. Anyhow I bought it as a rebuilder so it's about right