Hugh,

 

Yes.  Generally the fuel pressure sensor is located downstream of the engine fuel pump.  Fuel pressure warnings occur when the fuel pressure drops below 12-14 psi (12psi is a Lyc IO320 min). For me, any pressure below 20 is an indication of vaporization for my IO 320 and the boost pump comes on.  My standard pressure is 24-26 psi.

 

1. The engine driven pump can become super heated after the engine is stopped.  It can then cause severe vaporization and cavitation itself for quite some time -- until is sees pressurized cooler fuel.

 

2. If the boost pump is mounted on the firewall, it can become over heated in the engine compartment.  It is useful to open the oil filler door after the engine is stopped to allow hot air to escape that way.

 

An LNC2 equipped with the main fuel tank as a header tank, the fuel is always at a small positive pressure to the boost pump mounted lower than that tank where the boost pump is self priming and should be able to overcome vaporization.  However, it may initially have a problem pushing fuel through an overheated engine pump.

 

I have experienced engine pump cavitation while slow taxiing at OSH and it was resolved by turning on the boost pump.

 

For a hot start I turn the boost pump on even though the mixture control is set at idle cut-off for the initial attempt.  Vaporization can be reduced by keeping even hot fuel under pressure. 

 

Scott Krueger    

 

Has any one had problems with vapor lock on fuel injected LNC2 airplanes?

 

I am not sure vapor lock is the problem but I have had the electric fuel pump cavitate and not develop pressure when trying to start after the engine is hot.

 

Also how to you start a fuel injected engine with out electric fuel pump pressure?

 

Thanks

Hugh in Las Vegas the hot country