Beagle Pup - fuel pressure in the climb

[Final 3 Greens]

Hi guys. .. .I wonder if there is anyone with more than a few hours on Pups who can shed a bit of light?. .. .Before asking your opinion, let me state that the a/c will be going to the engineer for a check, but I would feel more comfortable having some anecdotal views before meeting the engineer.. .. .The a/c is a Pup Series 1 (RR/Continental) and we are experiencing a drop to circa 1.5psi pressure indication in the climb (2500rpm) when the boost pump is selected off at a safe altitude.. .. .This is half the value that the POH gives for a runup test at 1800rpm, but no figure is quoted in the POH for expected fuel pressure at higher rpm.. .. .I think I know the reasons why (got a helpful reply from a posting on Tech Log) and it revolves around the sensor measuring the pressure in the fuel line that bypasses the mechanical pump and feeds the carb direct in the event of a mechanical pump failure, using the electric boost pump. . .. .This is different to the PA28 arrangement which I am familiar with, where the sensor is located on a common line after the mechanical pump.. .. .So I can understand that there is a potential for a low fuel pressure indication if the Pup's mechanical pump is pressurising the main line, at the expense of the bypass line.. .. .The question is what would you expect the fuel pressure reading to being psi (approx) in the climb at 2500rpm, with the boost pump off? 1.5psi seems low to me, but I have no real benchmark to justify my feelings.. .. .If anyone has an opinion, it would be gratefully received.. .. .Thanks. .. .F3G

[mfds]

I was in my Pup 100 today and noticed the fuel pressure to be about 2psi on the mechanical pump only. With the electric backup its just under 3psi ..... .This is a normal indication for me.. .Hope this helps.

[Final 3 Greens]

mfds. .. .Thanks. this is helpful. I am still going to have our a/c checked to ensure that the gauge calibration hasn't slipped or that the mechanical pump is failing, but it appears that the fuel pressure indication is healthy so long as it shows some pressure!. .. .Its probably my lack of hours on type that is concerning me rather than the actuality.. .. . <img border="0" title="" alt="[Razz]" src="tongue.gif" />

[A and C]

In twenty years as a licenced engineer I,v seen two mech fuel pumps fail however I,v lost count of the number of indication problems I,v seen.. .. .I suspect that you will find nothing wrong with the system but all the same if it is suspect get it checked.