350 small cam Cummins, can I run OTR with this?

what's the plans for this truck over the road ya better know how to work on it

 

Those engines were in installed in 60% of all diesel trucks from after WW2 to mid seventies and are still around running strong. They made a million or so of them. What kind of bad rap can they have?

 

I believe Cummins ended small cam production in 1975. So either you are off on production year or it’s a big cam. The small cam was a great engine. The reason for the big cam was for epa emissions. Higher injection pressures required a larger diameter cam.

 

The comments about learning to work on it is because they haven’t made a mechanical 855 of any variant for close to 35-40 years now. Most of your mechanics are going to be younger than your engine and have limited experience with them

 

I agree, SC Cummings were great motors. Most old timers here cut their teeth on SCs. Not the most powerful, or efficient, but by golly, they'd chug on for years. In heard, BCs have bigger cam journals, allowing for less oil pressure, and better fuel mileage. IDK, maybe 1/2 gal. more mpg, but with all the wrecks out there, might be just as smart to drop a late model in. I think someday ALL trucks will have to comply with emissions, something a SC we never thought about. You want emissions? Watch this,,,,

 

The small cam Cummins is a good motor! They were prone to leaking head gaskets at the rear of the centre head and the front of the rear head or cylinders 5 and 6. the liners would get loose in the block at that location and leak coolant. Air would also get into the coolant and the cavitation erosion around the liner packing area would cause a hole to form in the liner and coolant would get into the oil. Machining the block to lower press fit liners would help a lot with this problem.
The 855 small cam started as the NH250 and was naturally aspirated later it was fitted with a turbo and became the NTC335, the next version was equipped with a after-cooler and became the NTC350. The next version was equipped with a higher flowing coolant pump a lower compression ratio and was the NTA400. The NTA400 did not last it had camshaft injector lobe failures and had hard starting problems when it was cool out. Notice I did not say cold. The next step in the 855 Cummins evolution was to go from a 2" cam bore to 2 1/2" cam bore which allowed a bigger injector lobe on the cam with a longer ramp.
The 350 small Cam Cummins is a good motor if you leave it at a 350. Rebuild it to a 0021 or 0160 CPL and time the cam followers at .041".