No return line in fuel circuit?

Re: No return line in fuel circuit?

by Roger Lee » 11 years ago

Roger Lee

131 5.38k 5.44k

Hi Kenneth,

The old AC and Pierberg pumps could more easily get away without using a re-circulation line, but the new Corona pumps may not be so forgiving and many have found out that due to higher pressures that some times they can have a rough running engine from too much delivered fuel and pressure. The electric fuel pump will increase the over delivered fuel pressure around .5 psi if plumbed correctly. Some have gotten away without the line and some haven't. It was designed to have the re-circulation line. This hose should be an easy and not an expensive installation. The
re-circulation line also helps reduce the chances of vapor lock. Installing your fuel lines in fire sleeve protects you from a fuel fed 2000 degree fire, but also helps a little in insulating the fuel lines from a little of that engine heat under normal running conditions. With cooler fuel always circulating this helps prevent fuel from becoming to hot within the lines and producing vapor. Tight cowled engines are more prone to this than an open air engine that is fully exposed to the air during flight.

Some times we only get away with something for 15 years. doesn't mean it can't happen to us.

As a 30 year firefighter I went to thousands of calls where something bad happened.
Everyone of the people always said, "Well that never happened before".

It did today.

IF you start having problems without the re-circulation line, i.e. rough running from a fuel delivery issue you'll know pretty much where to start looking.

---

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

Re: No return line in fuel circuit?

by Kenneth Hagesten » 11 years ago

Kenneth Hagesten

2 38 0

Thank you Roger
I have the old AC pump which has four years left to operate. I shall se what i will do with the return line, maybe best to install one. But the fuel pressure gauge should not be so vital, so i intend to skip that part of the system.

Re: No return line in fuel circuit?

by Przemysław Wiśniewski » 11 years ago

Przemysław Wiśniewski

65 247 3

If you will decide to fuel pressure gauge use this eletric one. Mechanical not looks good. You have to put another fuel line into your cockpit.

Re: No return line in fuel circuit?

by Kenneth Hagesten » 11 years ago

Kenneth Hagesten

2 38 0

Which do you mean Przemyslaw? You have not attached anything about that fuel pressure gauge.

Re: No return line in fuel circuit?

by Przemysław Wiśniewski » 11 years ago

Przemysław Wiśniewski

65 247 3

You can use two types of fuel gauges:

Mechanical: http://www.faston.pl/assets/images/fotosy/wskaznik_cisnienia_paliwa.jpg

and with electrical sender

http://img13.allegroimg.pl/photos/oryginal/38/60/86/67/3860866785_1

Second one is better because you don't need to put fuel line into cockpit for gauge. You installing fuel sender and go by electrical wire.