Deutz engine???
Just for thought.
In about 1975-76 I delivered a load of irrigation pumps to an irrigation co. in Stuttagart, Arkanas. They used primarily Deutz air cooled diesel engines on Irrigation stationary pumps.
They also had a new International 3/4 ton p/up in there that they were planting a 5 cyl Deutz engine into & was the 3rd truck that engine had been in....& they estimated the engine had over 300K miles & never overhauled....just brought in & serviced ever so often....air cooling fins cleaned, etc.. They said that at that time the 5 cyl fit the best.
They said that the owner was some rancher bullhauler from Mo. pulling some really long cattle trailer. They swore the truck, trailer, loaded etc was getting 16+ mpg and running w/lots power.....25-27mpg pulling empty trailer.....38-42 mpg running just straight p/up only.
They also had 2 others in there that they were servicing....1 International & 1 Ford. These engines already had a ton of miles on them.
Unique thing about the Deutz engine was that all cyl were virtually the same, just change crank, & bolt another cyl. unit onto the engine.....1 cyl, 2 cyl, 3cyl.....5cyl, 10cyl, etc, etc.
At that time an engine installed was approx. $1000/ cyl......5 cyl was approx $5000, & the 5cyl seemed to fit in p/up trucks the best.
Later I found a Deutz dealer in Dallas, Tx. All these numbers were closely verified by those folks....cost, performance, etc.
In around 1977 a guy that was leased to same Co I had semi's leased to put an aircooled Deutz engine in his old Kenworth. This was in the days that we usually got 3 1/2- 5 mpg in semi's.
Along with several other trucks, we ran from Cal. to Bayonne, NJ once. He consistently got over 8 mpg, closer to 9, & could run off from the rest anytime he wanted.
I've always remembered these engines, but never pursued, or had the money. I think the modern Deutz are totally different now-a-days....I guess.
Anyway, just a thought....