It's the way you treat your engine that affects longevity. Rolling coal etc will harm it, which you can do with a stock pump. The Europeans still get many thousand km from these MB engines putting out over twice rated power.

My superpump has 7.5mm elements and is set to 160cc (per 1000 injections). Apparently NA 617s were set up originally at about 42cc, the 617A 52 or 55cc(?).

The stock 5.5 elements are only good for about 65ish cc (depends, the injection takes longer with smaller elements which makes smoke and high EGT).

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1978 300D, 373,000km 617.912, 711.113 5 speed, 7.5mm superpump, HX30W turbo...many, many years in the making....
1977 280> 300D - 500,000km+ (to be sold...)
1984 240TD>300TD 121,000 miles, *gone*
1977 250 parts car
1988 Toyota Corona 2.0D *gone*
1975 FJ45>HJ45
1981 200>240D (to be sold...)
1999 Hyundai Lantra 1.6 *gone*
1980s Lansing Bagnall FOER 5.2 Forklift (the Mk2 engine hoist)
2001 Holden Rodeo 4JB1T 2WD