About 2 years ago I nearly bought a 300D, but got to know the new owner thru email discussion about biodiesel.
after a year she asked if I knew anyone with a 300D head for sale. It seems her mechanic recommended she replace the timing chain.
She agreed and he did the job.
A week later, the new chain came off and IIRC. destroyed the cam blocks, valves and there was damage to one piston.

The engine was repaired, but she was without her Merc for about 6 weeks. She sold it when she got it back, because she didn't trust that mechanics work anymore.

My interpretation is that he didn't install the chain joining link correctly when he changed the chain. The joining link pins need to be deformed by using the chain setting tool.

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Tony from West Oz.
Fatmobile 3 84 300D 295kkm Silver grey/Blue int. 2 tank WVO - Recipient of TurboDesel engine.
Josephine '82 300D 390kkm White/Palamino int.
Elizabeth '81 280E, sporting a '79 300D engine.
Lucille '87 W124 300D non-turbo 6 cylinder OM603, Pearl Grey with light grey interior


Various parts cars including 280E, 230C & 300D in various states of disassembly.