Latest Project - ET Westbury's "Wyvern" gas/petrol engine.

I've built a lot of steam engines, so I fancied a change and a bit of a challenge. Why not a IC engine?

As this is my first infernal combustion engine, I wanted something fairly basic and after looking at what was on offer I decided on a kit from Hemingway for a Westbury Wyvern open crank engine.

Well, it's been interesting. Looking around various internet forums would suggest that there are several mistakes in the drawings. Funny how you find this information after you fell into the hole! Anyway, work progresses; the main part of the engine is just about finished, only the carburettor to make.

Well, the carb's been made, so time to strip it all down for a paint job.

Back from the paint shop, mounted on a temporary board and ready to run

Well, it might look ready to run, but it won't! I've tried it on both gas and petrol but no joy.

A friend suggested that it might not have enough compression, so I opened the rings a bit - still no joy.

After a bit more investigation, I think it might be the exhaust valve leaking. Now, I have read that a lot of people have changed the exhaut valve to something more like the inlet valve, so I might try that.

I've also found a nice bit of oak to mount it on, so I've built up a proper plinth for it and I must say, it looks rather good.

Mounted on a proper plinth.

Well, after much messing about with ignition circuits and rebuilding the piston and both valves, I finally got it to run - but only for a few seconds!

Download Video: Closed Format: "MP4"

Shortly after this, my ignition coil gave up and I had to revert to the MiniMag system.

I could never get the engine to run for more than a few seconds and I began to suspect that the carburettor was at fault. A lot of people had criticised Westbury's design, so I decided to make a new one.

Looking around on the net I found a design for a 'Jag' carb. So I built it and tried again.