OM the D340 was a 4 cyl. version of the dual overhead cam engine the D343 used in larger scrapers & 988 loaders & the 1693 truck engine. I never had too much knowledge about them but did run a couple on the dyno for one of our other branches.
i had 2 619cs not to bad of a unit my were power shifts, they are ok for small jobs don't use much fuel and are some what easy to move. the only thing bad is you have to know how to run a old cable scraper can;t just put any one on them, any way i had very good luck out of bouth of mine you can still get parts for the motor but are $$ i sold mine last year wish i still had them