"ORVAL FAIRBAIRN" wrote in message
news
In article ,
"Kyle Boatright" wrote:
snip

If I was going to use mogas, I would consider a blast tube on the
mechanical
fuel pump, plus I'd do everything possible to minimize heat build up
inside
the cowling. Additionally, I would follow the EAA mogas STC's plan of
avoiding sharp bends in fuel lines. Beyond that, I might add a recirc
line
or purge valve to purge the fuel lines firewall forward before a hot
start.


The above precautions are just good design/building practice and should
be a part of the plane in the first place. Add a boost pump aft of the
firewall, to help keep a positive head on the engine-driven pump, too.

IMHO, the purge valve might ad more problems than it solves, in case of
valve failure.

Certainly something to consider. I have a gascolator under the cowl which
allows me to purge *some* of the warm fuel from the system. On the other
hand, I think the gascolator serves as a heat exchanger to heat the fuel,
which ain't good... I don't think my next plane will include an under-cowl
gascolator.

KB