I have a fairly clean running 617.950 in my '80 SD, and I plan a rebuild at around 500,000Km. I'm at 422,000 right now and it's original.

When it comes time to tear the engine down, what is the likelyhood of me having to replace the pistons? If there's no significant marring on the face or skirt of the piston I should only have to re-sleeve and re-ring right?

and Oil pump. Insanely expensive, is it re-usable after a rebuild? or can the pump itself be rebuilt?

I could possibly save $2000 on my rebuild if I don't have to replace the pistons....

and frankly, I can't wait to tear that thing down

__________________
RIP: 80 300SD
RIP: 79 450SEL
2002 E430 4matic (212,000km)
2002 ML500 'sport'

____________________________
FACEBOOK: PANZER450