Hi David,
No bash taken. did not quite make the picture clear enough. The GSU allows for the operator to do a "manual" lube without reverting to some other method. During startup the ability of the starter to spin the engine vs voltage drop combined with the rundown time will give an error with a context sensitive help promp i.e. "Rundown error - lube bearings". At any rate, without giving too much away, the bearings get lube 1-3 seconds after ignition and at much lower RPM. Also the all kero combustion is much cooler than propane so the bearing stress is obviously less.
Having said all of this, our experience have been that other factors contribute more to bearing life than the scenario described above. One of which is the ability of the BMT pump PID algorithm to control the pump ramp and flowrate accurately enough so kero can be introduced at much lower RPM than with the normal PWM controlled pumps, Kero or gas start. Where pump control does not allow for this, many starts get extended on gas to give the pump a chance to spool the engine at a more manageble (higher, hotter) RPM. Otherwise flamed starts is the result when inexperienced operators set parameters when pump params change and PWM settings need adjusting. The BMT system has no such settings internally at all, only absolute fuel delivery volume. Exactly how does it work? Very well...
Cheers
Andre
MD BMT