Graham Singleton a crit :
> I'm not familiar with 914 but I do remember that the return flow from
> the regulator must be unrestricted otherwise the back pressure will
> cause rich mixture? Because of the high flow rate required with all
> pumps running the return pipe needs to be at least -6 size.
Graham,
You're right.
I recently conducted some tests to verify this point. I pressurized the
regulator to the max 1,3 bar absolute, while running the pump. All the
flow was by-passed by the regulator, with no problem to maintain the
specified ambient + 0.25 bar.
While I was perched on a ladder, doing the pressurizing with a U-tube,
my buddy sitting on the wing forgot to switch the different pumps, so
some additional tests are necessary.
Best regards,
Gilles
http://contrails.free.fr
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