MEMBERS TALK… Smutterings on Fairbanks Morse
The recent feature of Fairbanks Morse engines at Amberley this year prompted me to look out some details on these engines, specifically relating to the magnetos and options available. Magnetos were an expensive bit of kit and it is fair to say that many engines sold to the USA market were equipped with battery and coil ignition. In the UK however things were different and nearly all engines sold with a magneto.
Take the Fairbanks Morse Z type, back in 1925, the 3hp Z sold for an Export price of $138 when equipped with the Model R rotary magneto. The R magneto if bought separately would cost $22 or about 18% of the bare engine price. The American Bosch AB34 trip magneto (which replaced the AB33) would have cost $45, about 38% of the bare engine cost making this an expensive option.
A Sumter E15 rotary magneto (made by Splitdorf after Sumter was acquired sometime before 1919) would cost $19 whereas the option of a Sumter E1 oscillating magneto with plug-oscillator (Low tension ignitor) would come in at $29. The FM R type rotary magneto and the equivalent Sumter option were comparable in cost but the American Bosch option is considerably more expensive. As the AB33 magneto seems to appear on many UK engines, it may be they were specified by the agents or perhaps users here were familiar with the quality/reliability/easy starting of the Bosch trip magneto and were willing to pay the extra..
Battery ignition was only an option for the 2hp model saving about $16 on the model R equipped engine price if had with disc flywheels (a saving of $3 on the spoked flywheel variant). Upgrade kits were available to replace earlier magneto/ignition types with the R type magneto and spark plug. Depending on engine size, the cost for this kit ranged from $34 to $39
Regarding engine sizing, based on the spark plug Z type with R type magneto being fitted, the Export price for the 2 hp engine was $86 held for both hit and miss and throttle governed engines. The 3hp Z type engine cost $138, the 6hp $210, the 10hp $515, the 15hp $630 and the 20hp $1045. As the 2hp was suitable for most duties and 50% more power from the 3hp came at a 60% increase in price, it’s clear the 2hp was an economical option and perhaps why the 3hp is less often seen in the UK. The 6hp is good value at 3 times the power of the 2hp and only 2.4 times the price but is probably too large for most applications..
Information gleaned from the FM archive kindly donated to SEAMS by Mike Godley
Richard Amos, SEAMS Historian