Hi guys,
I own a 420 SEC (W 126) form 9-1989 (120000 km); some time ago I noticed a ticking noise at the right side of the right cylinder block,with the engine idling (tapping valves??).

The normal idling speed is irregular (like stumbling/misfiring)and it seems to me the fuel consumption has slightly increased lately....

The MB dealer supposes a malfunction of the valve tappets and/or rockers which need to be replaced, maybe the camshaft as well...!?

Has anyone experienced the same problem ? If so, please let me know what the diagnosis was....

Thanks in advance,

Rémy K.
Netherlands


[This message has been edited by cremer (edited 04-11-2000).]

THE TICKING AND MISFIRING MAY NOT BE RELATED,IT IS COMMON FOR 116/117 VALVE TRAINS TO HAVE TICKING THAT COMES AND GOES.SEEMS THE ROTATORS INTERMITTANTLY COME IN CONTACT WITH THE HEAD BOSSES THEY ARE RECESSED INTO,NOT A MAJOR MALFUNCTION.
FOR MISFIRE CHECK CONDITION OF WIRES AND CONNECTORS,INJECTORS FOR CLEANLINESS,AND FOR VACUUM LEAKS. M.F.

If the ticking is persistant and constant, I have replaced many rocker arms on these engines. The miss will probably not be related.

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Donnie Drummonds
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1981 280GE SWB
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