how can i stop noisy tappets?

Hi,
Sounds like you have sludge in the oilways to the hydraulic tappets. They rely on a constant supply of oil to keep them quiet. In the old days, flushing oil was sued to clean out the system. If you can get this (possibly Halfords or a good motor factors) drain the oil, run the engine with the flushing oil in, then drain this out and refill with fresh oil. If you can't get flushing oil, you can get a can of engine cleaner (again from Halfords...costs around £10). Put this in the engine with the oil you have in there, run the engine for around 15 mins, then drain and refill with fresh oil and new filter. This should do the trick.
Best of luck!!

Denis Langley (Autocure Mobile Repair)
November 2009