Another visit to Norfolk.

The first trip to Brancaster looked at a B class two stroke that was well ahead of its time. The return journey discovers another quite amazing piece of engineering from John Duffield. Again a 15cc two stroke, but this time with an eccentric vane supercharger built integral with the engine. This was the last motor to be built by John and probably was never run in this form, but with the supercharger removed and the engine fitted into a purpose built lightweight hull it was run successfully by John Demott in the 70s and 80s. A detailed look at this engine will follow in due course.
Feb 08

This 15cc four stroke boat engine was retrieved from the same source as IGO and EGO in the hydro pit box. It qualifies as a 'wotzit' as no details about its origins are forthcoming. It follows the trend that was prevalent in the 30s of having a large flywheel towards the bow of the boat. The extension shaft and coupling can be seen below the contact breaker, which is moveable to alter the timing. The size of the plug is a good indication of the age of the engine as plugs up to 18mm were used through the 30s before 3/8" and 1/4" model sizes became available. The brass fitting, just in front of the push rods is the crankcase breather. Lubrication seems to have been via what splashed round in the crankcase or was blown into the timing chest. The engine now resides in a large free running hydroplane that also comes under the 'wotzit' category.
Oct 07

A ‘tiny treasure’.

This delightful little engine turned up on eBay with no indication as to its identity. The bidding pattern soon showed that at least two people had a shrewd idea that it was more than just a 1cc diesel engine as described. By the end of the auction the motor went for a significant amount and it transpired that both bidders knew each other well but were unaware of their respective eBay IDs. What both bidders suspected, and was later confirmed was that this was a prototype rear rotary valve engine and centrifugal clutch built for rail racing by the ‘North London Maestro’ Arthur Weaver. Weaver was actively involved in tethered car and hydroplane racing as well as being in the forefront of the rail racing scene. Many examples of his standard 1cc front induction engine exist as construction of this was serialised, but he also constructed a number of different two and four stroke engines. His modelling and engineering were superb, winning him many awards, and examples of his work are now highly sought after. June 07

The Kings Lynn Club had three confirmed tethered hydroplane fans who refused to be bound by normal practice. Messrs Stalham, Chapman and Duffield could always be relied upon to produce something unusual. This 15cc two stroke dates from the late thirties and was the work of John Duffield of Brancaster. It is very advanced for its day having a flat topped piston and a forerunner of schnuerle porting as well as rear rotary valve induction. What makes this engine especially interesting is that as each development was made the discarded parts were not consigned to the bin but kept with the engine so that there is a complete record of development from the early water cooled head and petrol carb to the highly sophisticated micrometer fine adjustment version shown on the backplate with the ignition CB.
First used in Lynn 1 which was carved from solid pine and later in a more conventional Lynn 2 this motor had its last run at the 85^th anniversary meeting of the Victoria Club where it won its class at over 30 mph. Dec 06

This unfinished 30cc flat twin engine has recently appeared on eBay. It was the work of Stan Clifford, one of the most famous tethered hydroplane exponents over the decades, with boats such as Chatterbox, Blue Streak and the all glass fibre ‘Polyester’. Clifford held the British record for no less than 14 years from 1922 with Chatterbox II and III.

The engine is ‘as seen’ but is complete with all relevant drawings, crankcase and cylinder head patterns. Unusually it was intended to be water-cooled, almost certainly due to the flat twin configuration and was designed by Edgar Westbury. (Could this have been the origin of the Crafstman Twin?) The vendor also has a set of plans and details for a kipper box hydro intended for the engine.

It is to be hoped that someone can take on the responsibility of finishing such an important engine and construct an appropriate hull.

Thanks to Paul for the photos and information.
June 06

Edgar Westbury designed engines probably powered more of the early tethered cars than all other engines put together. Of these, the 5cc Kestrel was certainly the most common being installed in several well-known cars, such as Lucy Gascoignes MG Record Breaker, as well as any number of other cars, until commercially produced engines became freely available. The Kestrel was designed around 1935 and intended for home construction It has several interesting features, such as a rotary disc valve running on the inside front face of the crankcase.

The engine illustrated is hardly a pristine example, but is included for its historical importance, as it was part of Colonel Bowden’s engine collection and is recorded as being one of Westbury’s original ‘test bed’ development engines, used to prove his design.

Feb 06