My suggestion would be to see if it will run on WD-40 sprayed into the intake. The reason for the low compression can be determined using a leak down test where each cylinder is pressurized while at top dead center and listen for leakage into the exhaust, the intake, or the crankcase. Hot air from a heat gun into the intake while cranking is a good way to start a reluctant diesel.

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'97 E 300 D