Reply To: Douglas SV54

[sidevalve5]

Hi Will,

Many thanks for that. Cox and Turner is one of the suppliers I have for parts and they are usually my first port of call for engine spares. Can get rings a bit cheaper from a manufacturer, but prefer to use Cox and Turner because they are fellow enthusiasts.

Have fitted new rings and ground in the valves on many engines. But some I have worked on have been left stood for years in damp conditions. The valve contact surfaces and the seats have become very pitted with corrosion. Managed to lap most of them out, but the contact surfaces widened, ridges and grooves formed too. Got good compression to start with, but after some hours work it tailed off. Put a thin rubber glove over the exhaust and the carb inlet, it blew up when the engine was near the end of the compression stroke. Am going to get the valve seats cut and the valves themselves re-faced. But as the contact surfaces are now so wide, am going for a 3 angle cut. When I have it done will post something on the forum to share my experience. If anyone has had this done, would like to know what they thought of the results.

Best wishes,

Grahame