I have just aquired a 1987 300DT with what I suspect are major engine problems. Symptoms are:

hard shake at idle, no power below 2000 rpm, miss at speed. Compression test indicates marginal (300 psi) compression in most cylinders, # 4 lower. #4 appears to be nearly dead at idle, #2 and #3 also low on output. A leak test shows leakeage past the rings into the crankcase. Valves show minimal leakage.

The radiator is new, leading me to suspect a failure and severe overheating.

Does anyone have any experience with such conditions in a 603? Is there anything I can check before starting a complete rebuild (I will be doing this myself)?

I have searched all the listings I can find, and have the following ideas:

Cracked head -- the car runs cool and doesn't appear to have any exhaust gasses in the coolant, nor coolant in the oil.

Stretched chain and bad chain tensioner -- could account for the poor compression, but what about the leakage down the cylinder walls?

The motor oil is VERY thick -- my brother suspects "motor honey" plus probably 50 wt oil (like his 75 300D -- another story). This would explain the lack of oil consumption (hasn't used any in 1600 miles).

I plan to check the chain and change the oil this weekend -- if the rings are just stuck I suspect Mobil 1 will free them up. If the cylinder walls are shot, it will smoke like crazy when I put decent oil in it.

Thanks in adavance!


Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!