The M115 230 engine is a four cylinder petrol engine used in the W115 and W123 models of the 70,s and 80,s. The engine produced 109 BHP in the w123 models and is thought by some to be somewhat underpowered and rather an industrial power unit. however it does have a certain charm and appeal.

the unit was fitted with  a single Stromberg carburettor. The engine is a relatively straightforward engine giving very few problems, the simplicity and relative size of the unit make it simple to work on even at the roadside

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