My Victa V40 2 stroke wouldn't start. so I decided to change the spark plug.

The existing one came out easily but it came out with a spring like coil wrapped around the thread. What is it, and how do I get it back in?

Engine is a Briggs and Stratten 2 stroke.

Les, October 2012

Which end of the plug is this spring like coil attached to? The end that fits into the engine or the other end the spark plug cap fits to?

From the sound of it, I would suggest it is the plug cap end, and when you've pulled off the cap, the metal ignition lead connector has pulled away from the lead and remained on the top of the plug- it is like a very tightly coiled spring with a hooked leg on one end. If so, you will need to re-attach it to the plug lead before re-fitting the cap to the plug.

pleasant, October 2012

Really? Depending on how old it is, the V40 should have either a Victa 'own label' 2-stroke engine (made of cast iron), or a Briggs & Stratton 4 Stroke engine (made of light alloy).

If it really does have a B&S 2-stroke, it's been re-engined. B&S 2-strokes are rare, and were never fitted to Victa mowers as far as I know.

Regardless, it sounds like the thread has pulled out of the head when you removed the plug. I've never seen this happen on an iron head, but on the alloy ones, it can happen if the plug is over-tightened. In any case, it's technically possible to repair it using a 'helicoil' insert, but a new cylinder head is the preferred repair. Cheap if it's a side valve (or a 2-stroke), not so cheap for an OHV engine.

phil_saunders(a)bigfoot.com

Phil Saunders, October 2012