3 inch scale Burrell agricultural engine

A 3 inch scale Burrell 6nhp agricultural engine to the Plastow design, this one has come to us from a long time customer, now in his ninth decade and clearing out some of the larger toys from his collection.

An older engine, it was rallied regularly up until the start of COVID, since when it's been stored in the owner's dining room.

The boiler had a preliminary hydraulic test on arrival. Amateur built, it has several stay heads that showed beads of water, although nothing that concerned us enough to prevent steaming it - as expected, they were dry under steam. Firebox crown has more stays than called for in the design - untidily fitted, although dry under test.

The engine itself runs very well - missing its regulator and gland when it arrived, we've made and fitted one of our graphite PTFE regulators, which is light to operate and leak free.

In steam the mechanical pump worked fine, the injector didn't - clogged with limescale when it arrived, it's been cleaned out but needs replacement.

The mechanical lubricator doesn't work when the engine's running in reverse - curiously it's connected to the expansion link rather than the valve rod as shown in the design. Driving a lubricator from the expansion link is a great idea where the link has a fixed pivot (as in Walschaerts gear - it's how we drive the lubricators on the engines we build ourselves) but not so good where the link moves, as in Stephensons.

The engine runs on rubber tyres - the front nearside coming adrift, it needs some adhesive - which makes it quieter on the road, whilst slightly raising the gearing.