Vintage Thing No.12.2 - The Trojan Utility engine again

I often visit the Launceston Steam Railway. It's a kind of drop in centre for the oily fingered and connoisseurs of Vintage Things. Since last year, they've made a few changes to the displays in the workshops. For the early part of the summer the place was closed but on a wet and dreary day last month I dropped in and - lo and behold! - found a cut away engine of the Trojan two stroke engine.

Previous examinations of these Vintage Things offered some answers but raised more questions. A close look at the engine was what I really needed - don't bother looking under the bonnet, it's under the floor.

There's always been at least one Trojan car in the little museum at the Launceston Steam Railway but now there's a van this splendid cut away examples of the extraordinary engines these things have.

But don't worry - no working examples of Trojan engines were harmed or destroyed in making this display. I was assured that the cut-away was produced using a very old engine that had been long abandoned in a ditch and if you look closely you can see how pitted the components are under the Hammerite paint.

I paid this exhibit some close attention and soon came to the attention myself of one of the museum's helpers who knew the proprietor and also owned Trojans. I took the opportunity to ask him some searching questions and now feel that the answers are beginning to outweigh the questions on these machines. Unfortunately, I didn't ask him his name so can't credit him in enlightening my darkness.

Here's the horizontal cylinder block, such a long under square affair that I doubt if the Trojan even featured on the contemporary RAC taxation rating system.

Note the transfer ports and the cut out at the top of the wall separating the cylinders. This is what makes it a split single - the combustion chamber is shared. The cylinder head is detachable and there are threaded inserts in the top of each piston. However, these are not designed to be removed after fitting - at least easily - and are treated with a saline solution such as ammonium sealiac (I think that's what this chap called it). The idea is that they are corrosion welded into place. Consequently, I can't imagine two-stroke Trojan's ever suffering from head gasket problems. Click on the image to enlarge it for a better look.

These are the moving parts of the Trojan engine, all seven of them. What strikes me most is how flimsy those conrods look. They genuinely are designed to bend. Each pair of pistons has a leading piston although they catch up with each other at top and bottom dead centre. By comparison to those tall thin pistons and conrods that look like by Giacometti's idea of a Daddy Long Legs, there is an enormous flywheel of steam engine proportions. It all looks like it shouldn't work but it does and beautifully.

I asked my informant if the Trojan engine had ever been tuned and hes aid only for trials use. "It's a slogger and goes on for ever, albeit very slowly. I'd use mine more often if it weren't for the speed of today's traffic."

Perpetual motion? Not quite but nearly indestructible. Hounsfiled designed the Trojan for extreme economy and reliability and the complication of a four stroke with all their unnecessary valves ruled them out from the word go.

The chassis was described to me as an open punt and the petrol filler is in the middle of the bonnet. It lacks any sort of seal so - no problem - Hounsfield put a water drain tap on the petrol tank that feeds the carburettor by gravity. There is then a long induction tract that must enhance the Trojan engine's torque characteristics even more.

Hounsfield almost deliberately defied convention in so many ways with these cars but wisely ensured they looked reasonably normal, at least from a distance. That way the punters weren't put off. Wasted space was not so much of a consideration as extreme economy and reliability.

Apparently, he made more money out of a design for a folding camp bed for the British Army. I reckon he's one of the unsung heroes of British automotive design.

The old van in the background is something of a film star. It appeared with Derek Nimmo in One of our Dinosaurs is missing painted a different colour as a laundry van. And - no- this Trojan was not the dinosaur in question.

It's always interesting to look at someone's vision of motoring for the masses. There's something very egalitarian about Leslie Hounsfield's Trojan. I look upon it as a kind of English Model T Ford. They were contemporaries and both were unconventional in their approach to putting the world on wheels. In a parallel universe Laurel and Hardy might have driven/smashed up a few.

I asked about the later supercharged version, the engine drawing of which had intrigued me so much right at the start of my investigations into all thing Trojan. Were any of these tuned?
My informant couldn't say. He thought not.

"There must easier ways of going quickly," he said. "They were terribly thirsty, though, and had a very distinctive sound. When the Perkins P3 diesel was offered as an option, demand for
the old engine almost finished over night."

So, while the original oh-my-God-the-conrod's-are-so-spindly version has no sporting pretensions beyond a successful career in classic trials, the jury's still out on the blown variety.