High Fuel Pressure Investigation - Part 2

TLDR

• Continue from Part 1; Investigaing the high fuel pressure issue

Details

I’m still investigating the high fuel pressure issue. I compiled a list of TODOs for the next few days.

Investigation TODOs

Removing return lines

I started to remove the return lines from the airplane section by section for two reasons:

1. I want to inspection them for restriction
2. I plan to replace them with rubber hose, which has almost 50% more area for the fuel to go through.

removed the line between fuel selector and cockpit bulkhead

Borescope

As I removed each segment, I took a borescope camera through the lines, and checked for debris, kink marks and anything suspicous.

So far I have not found any smoking gun.

Fuel Selector Check Valve

I also took this opportunity to install a checkvalve (0.8-1.2 bar) to bypass the fuel selector in case there is a total blockage on the fuel selector itself. The check valve was recently introduced in the latest build manual, so I did not have this when building this part of the airplane before.

Today I only got the install started, only one T-fitting was test fitted. A few more hours to go.