A few months ago, Tony Munday (owner of SafeAir1) contacted me about the pitot mast I purchased from them.  There were apparently some instances of cracking in the weld that joins the mast to the mounting plate and he is replacing all of them free of charge.  He sent me the new mast, but I’ve been so busy with Phase 1 and other maintenance that I haven’t had the time to do the swap.  I had a good chunk of time today, so I decided to take care of it.  Drilling out the old mast was fairly straight forward, but I decided to attach the new mast with screws in case I ever have to take it out again in the future.  I dropped the new mast down through the hole and then drilled all nine spots for #6 screws.  I then pulled the mast out and added nutplates on the mounting plate.

I dimpled or countersunk the surface and then attached the new mast with some stainless steel torx screws.  I transferred the mounting holes for the screws that mount the pitot tube on the mast and then installed everything for good.

The forward three holes go through the spar flange, so I had to countersink there.  The others I could dimple.  For some reason, the new mast is much stiffer than the old one.

I’ve always had a slightly erratic fuel flow.  The fire sleeve I added a couple of months ago helped, but didn’t fully resolve the problem.  Although I still suspected a heat problem, I called Dynon to get other ideas.  They sent me a document on diagnosing fuel flow issues and wanted me to remove the 90º elbow on the outlet before trying anything else.  I decided to call EI who makes the sensor to see what they thought and they told me that the number one cause of an erratic fuel flow sensor was a bad electrical connection to the sensor.

I pulled the heat shrink off of the knife splices for the three wires going to the sensor.  I re-crimped them and squeezed the splices so that they’re much tighter.  I then re-heat-shrinked them and took it up for a short flight.  The fuel flow was rock solid.

Update: with over 5 hours on the plane now since redoing the connections, I’m pretty sure this is now resolved.