It has been requested that I fix a 3.5 hp lawn mower, sone one has run without topping the oil, so con rod needs replacicing also top bearing, so far, may need new piston, any idea where I can get the bits, the job is easy, who to supply me the parts is the question.

steve h, September 2012

New top bearing = new crank case, whoever makes it. In the case of Challenge, it could be Tecumseh, Briggs & Stratton, or (more likely) a Chinese Honda rip-off. Look on the block casting for a white label. If it's a chinese engine, it will have a sticker on it with an obvious Chinese manufacturer name - in which case, forget about sourcing parts. IF you can find anyone willing to order them, it will take MONTHS, and will cost more than a new engine (which you can get for £85 new in a box).

A re-engine will be MUCH simpler, and cheaper. Any standard engine up to 5 HP will bolt straight on - just check the crankshaft length. A Briggs & Stratton 'Classic' 35 is an obvious choice - £20 off ebay for a running one.

phil_saunders(a)bigfoot.com

Phil Saunders, September 2012