I am considering rebuilding by 300sd w126 617

and i have been checking prices....and it just does not ad up
1200 bucks pistons,
200 bucks liners,
200 bucks gaskets,
200 bucks barings,
200 bucks top bearings,
oh and what about valves,

400 bucks oil pump...

So what really needs replacing... I read someone say they hardly ever replaced the cam shaft bearings...

Can a rebuild be just new rings, valve guide seals, gaskets, and seals...
or do you also need inserts....

I would probably do rings and liners since these two items wear out quickly (in comparison to the usual piston in this case). If you are rebuilding out of nessessity then plan on spending decent cash incase you have wasted pistons.
Bearings can be gauged and determined their remaining life obviously.
If pistons are good...I would reuse them...those things are big money..

would you replace the oil pump... seems to be big money..

also what can be done to the turbo....

what do you do to the head...

i guess you would also replace the timing chain...

And guide rail.

How many miles are on your 300SD?

the oil pump can be examined and if not too worn reused. there are specs on all the stuff that the machinist can look at and measure, etc. yes always chain guides. usually as noted above the pistons can be reusd. dont scrimp on liners, they are cheap.

we always measue the block for twist and deck as nec. along with the head.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Don't order any parts until you have taken the engine apart and measured everything.

GET THE Factory Shop Manual for your car... this tells EXACTLY what the tolerance is for everything.... so you know if something is past using again...

Typically on these engines you can reuse the pistons and the oil pump....

The clearances on the piston to bore are so tight that you either need new pistons and rebore the liners... or new liners and use the old pistons ( the bores are still bored to fit the individual piston going into it ) and the liners are WAY CHEAP compared to pistons...