> Fred;
>
> In regards to to fuel pressure at full boost. On takeoff at full boost
> the fuel pressure was 1.7 PSI and no fluctuations.
>
>> At sea level the fuel pressure reads about 1.2 PSI and through about
>> 6.000 feet the PSI will vary from 1.2 -1.7 PSI.
>>
>>At 10.000 to 14.000 feet I usually see about 2.5 to 2.9 PSI
>>
>>At 17.000 I normally see about 3.5 PSI.
>>Jim Brown
>>N398JB
That all very intriguing. What kind of fuel pressure instrument?
Direct reading or electric? For direct reading, it sounds as though the
instrument is not sealed, thus the Bourdon tube inside is exposed to
cabin pressure. Similar as to a remote sender, if it's not sealed. But
boost showing only 1.7 psi has me stumped. There should be 4.1 psi in
the airbox (relative to 29.92), and thus in the float bowls also.
Something greater is needed for fuel flow, or so I thought. Maybe the
answer is in why your not seeing around 3.6 psi nominal per book near
sea level? Though obviously flies just fine.
Best,
Fred F.
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