Vincent Amanda engine.

Took Friday afternoon off to go and help Nick Meikle with the water scooter
engine. The thing has loads of compression and practically no flywheel so
Nick had been having trouble getting it over more than 'lump' with the
comedy pull starter thoughtfully provided by Vincent.
Anyway, we strapped it to a heavy steel trestle and after much priming,
pulling and sweating it was away - what a racket! The exhaust system
consists of a approx pipe from each cylinder leading to a length of thicker
pipe and then a narrow tail pipe, no baffles, packing or anything else to
dull the effect. This may of course have all been part of the Water Scooter
experience, but in a concrete walled back yard it was a bit much.
A length of flexy pipe and Burgess silencer reduced it to a bearable level,
trouble is we could then hear the dreadful mechanical noise the thing was
making. Two-strokes shouldn't sound like that - time for a bit more
investigation, can't be too much wrong though as the engine appears
virtually unused.
NHH
Reply to
Nick Highfield
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I've also got a twin Amanda marine engine that appears to be virtually unused. It's got a lot of white ali oxide powder on it - actually dusting on the surface - and the surface of the castings is far more pitted than I'd expect. I suspect that the metal is high in zinc to get a low surface tension for good castings.
I suspect it has a Dynastart arrangement although I've never tried it, but the pull cord seems to me like a genuine comedy item as Nick says - nearly as useless as the one on the ABC auxiliary engine. The engine weighs so little that it is difficult to do anything with it unless its bolted down to something very solid.
The exhaust was intended to exit underwater of course, so it only deafened the fish. Probably the screw acted as a flywheel.
It is hard to see how the company that for so long produced high class, expensive motorcycles could become involved with these curious devices.
I also correspond on the Vincent Owners Club JTAN list. Might I copy your comments across to that forum, Nick? It might raise some interesting remarks.
Regards,
Kim Siddorn.
Reply to
J K Siddorn
Pass on to VOC by all means, please post any interesting comments generated.
No sign of dynastart or attachment point for same on Nick M's engine, infact I would be surprised if the Amanda carried a battery, so comedy pull start it is.
Prop is driven via centrifugal clutch so no use as flywheel at starting speeds.
Exhaust system sweeps up from engine so doesn't look to be heading for the water, may be some missing of course. I suspect that the raucous engine noise would be less noticeable on open water and would anyway add to the sense of speed.
Have you and Nick M. compared notes? I'm sure it would be interesting to do so as many parts of the engine have a prototype/pre-production look about them infact some can only be described as "let's just get the thing going" bodges, e.g. it looks like mechanical noise could be no more than two parts of the cowling vibrating together due to incorrect number of washers in the stack that controls their position!
Reply to
Nick Highfield

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