> Downstream head losses in the
>remainder of the complete system would confirm that the engine pump is
>having to suck (ie put much of the fuel line at less than atmospheric
>pressure ) to draw along the fuel; This would increase the risk of vapour
>formation.
>
>It would reinforce the need to install the auxiliary pump as low as possible
>and with as few flow restrictions as possible between it and the tank. Some
>types of pump (eg roller cell) aren`t good at sucking and, if they become
>unprimed (eg by vapour locks), aren`t good at getting things going again.
>Duncan
Exactly, and the Facet isn't too good at pumping vapour either. The
slightest air leak on the suction side, (possibly it will not show a fuel
leak under gravity either,)will have a similar effect on fuel pressure at
the engine and with low fuel levels prevent full power being developed.
Graham
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