37-50 LaSalle original engine needs attention

[Ittenbacher Frank]

My friends LaSalle ran very well, mechanically quiet and pulling strong, but smoky, burning lots of oil. Last week he opened the engine and found many upper piston rings broken and all four pistons on the left bank badly broken. We assume one of the previous owners had overheated the engine, additionally probably running the left bank lean from a leaky intake manifild? And experience on that?

We are quite sure the engine lower end has never been apart. Bores, bearings cams and so on look nice, nothing scored or worn from high mileage. We will measure the bores carefully before deciding what to do. Most probably we don't need to bore the engine. Any suggestion where to find NOS pistons with standard diameter 3 3/8" for the 322 cdi? Are there differences between 1937 and the following years? His engine number is 2256898. Another question: What tools had been used for the slotted (!) bolts on the bid ends? Thanks for suggestions.

Edited September 30 by Ittenbacher Frank (see edit history)

[Ittenbacher Frank]

here are a few photos of one of the original pistons. Note the number cast inside.