Reply To: When to re-ring

[sidevalve5]

There were a couple of errors on the original post. The Villiers engine was a VIIIC and the top ring gap ½” up from the bottom of the cylinder 0.063”, the second ring in the same position 0.054”. Also should have said the Hastings recommended clearance between the axial height of the ring AND THE GROOVE should be between 0.001” – 0.003”. Apologises for any confusion.

Hastings Piston Rings have written their advice to include tuned and high performance engines. Ours are on the very opposite end of the scale, so should think the tolerances can be greater than the advised. But the closer you can get to it, the better the performance will be of any engine.

The post was nearly exclusively about re-ringing, when to do it, how to measure a cylinder bore with just a ring and feeler gauges. Also where to get rings if the original parts are no longer available. After disassembly, obviously other aspects of the engine need to be inspected and work undertaken as required. FYI the Gravely D had very worn guides, so had some made by a mate who has an engineering business. The Villiers had worn main bearing bushes and play on the big end. Enquired at a Villiers specialist engine rebuilder and he wanted a huge amount of money to do it. Managed to get the bushes and big end rollers. A vintage motorcycle racer could do the crank, press in the bushes and ensure everything aligns. What surprised me about that engine was the amount of wear on the rings, bushes and big end rollers. Yet the cylinder bore was OK!

Do not wish to get into a ding dong battle of opinions. Will only reply to a comments if I think it will make a positive contribution.