Mamod SA1 Roadster

This is an early Mamod SA1 Roadster, a rather fine model steam car made in England in 1976. The early models had six spoke wheels and a methylated spirit burner rather than the more modern, solid-fuel type.

We were delighted by the the fact that it had not been “restored” or generally messed-about with. It’s what we would call “a good, honest little motor“.


Preparing to steam

There were a few minor issues that we had to resolve before we got steam up:-

1. The safety valve was jammed. This was simply a build up of limescale. A couple of hours soaking the valve in vinegar fixed it.

2. We ordered a set of replacement SA1 drive bands from a Mamod specialist to replace the knotted band and stretched bands it came with. Unfortunately one of the bands that arrived was too long. Fortunately, the the band was not joined together particularly well either! So I was able to undo it, shorten it and the refasten it again properly. Now it is fine. The other band was too big and too fat. Fortunately I had a spare that I was able to cut to length. This was a metric-sized, unjoined 500mm x 1.5mm diameter band, made in Australia apparently. It fitted perfectly.

3. Poor little SA1 obviously had not seen an oil can for decades! So we took a little time to ensure that we lubricated everywhere than needed lubricating and let the oil “soak in” for a few hours. We used thick “steam oil” in the cylinder and piston, and much lighter 3-in-1 on all the other moving parts.

4. Whenever we take delivery of a vintage engine, we routinely replace all washers and sealing rings. We also smear the safety-valve and water-level plug threads, fibre washers and mating faces that form a seal with a thin film of silicone grease. This helps them seal better and makes them easier to insert and remove. Not merely does this make the machine safer, it also makes it run better. Fewer leaks = faster engine.

Actually, as any steamhead will tell you, all the above is actually fairly trivial. The important thing is that this is a lovely engine and takes pride of place in our collection.

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