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Maintenance

Annual (and more, unfortunately)

Annual is done!  And for the second year in a row, it was much more than just the annual (last year was remove/repair/reinstall right fuel tank).  Extra things I had to do this year: 1) return the strobe driver box for repair since the rear strobe wasn’t working 2) send ELT for repair for a ridiculous $400, 3) replace a fuel line that I may have slightly twisted while removing the fuel filter for inspection, but replacement was probably unnecessary, 4) repair leak at the brake reservoir due to ridiculous Van’s plastic fitting, 5) replace two leaky fittings at the brake pedals and re-bleed.  There were also a few minor inconveniences like painted-on screws on some of the inspection panels that slowed me down a little.

Next year, I swear it will be easier and faster.

Flying again!

After almost 5 weeks, I’m back in the air.  Did a quick post-maintenance flight on Friday evening, and everything is working well.

Fuel Tank Repair

During our first annual inspection, Kelly noticed a slight blue stain under the right wing.  Aviation fuel is dyed blue, so when fuel leaks and evaporates, it leaves a blue stain.  After taking a closer look, it appeared to be leaking from around the outlet of the fuel tank.  It’s a small leak, so not dangerous, but still needs to be fixed.  While we were still building, I noticed a slight leak in this area, between the flange that the fitting screws into and the inboard tank rib.  At the time, I repaired it with some fuel tank sealant around the outlet, and that had held up to now.

Apparently, the right way to fix this is to get inside the tank and re-seal it.  We also had an issue where the fuel vent dripped fuel when the tanks were very full, which indicates a leak where the vent tube attaches to the fitting inside the tank.  With both of these problems, it was clear we needed to get into the tank to fix it.  This requires removing the tank and cutting an access hole in the back of the tank.  Though I could have done this myself, we opted to send the entire tank to Van’s for repair.  Since this was one of the pre-built parts and it was clearly built incorrectly, Van’s was willing to take responsibility for the repair.  Here’s what it looks like with the tank removed (the tank *is* the inboard front part of the wing).

Van’s turned the tank around very quickly, so Kelly and I were able to re-mount it last weekend.  In the meantime, we finished the annual inspection, so the airplane is ready to fly again, once we get some good weather.  It’s been a month since the last flight, so I’m eager to get in the air again.

Oil Cooler Restrictor Plate

As the temperatures get colder, it’s becoming apparent that I’m getting too much cooling via the oil cooler.  Even on a reasonably cool day (ground temp in the lower 40’s), I was having trouble getting the oil temperature to 160 degrees.  It should be around 180 to ensure more of the water in the oil evaporates.

To fix the problem, I created a restrictor plate for the oil cooler air inlet.  Basically, this plate limits the amount of air that flows through the oil cooler, which results in less heat transfer in the oil cooler, which yields a higher oil temperature.  Here’s a picture.

I drilled three 3/4″ holes, rather than just make the plate smaller, so later I can further reduce airflow (if necessary) by putting some aluminum tape over the holes.

I did a quick test flight and saw temps nearing 180 in cruise, which is exactly what I was looking for.

 

Repairman Certificate

Finally got around to getting the repairman certificate.  The name is a bit of a misnomer–no authorization is required for anyone to work on the airplane, but the repairman certificate allows me to sign off on the annual inspections, the first of which is due by the end of February.  A guy from the FAA came out to check out the airplane and my paperwork (especially the builder log) and issued the certificate.  I’ll get my “real one” in a few weeks.

Update: here’s what the permanent one looks like.

 

Oil Change

Poor Kelly has had only a few short flights, and she’s already gotten roped into helping with an oil change.

She was in charge of putting all the new oil (9 qts) in, and she also took a few pictures.

Here I am draining an oil sample.  At each oil change, we take a sample and send it off to a lab for analysis.  They then send us a report, comparing it to previous samples, and let us know if there’s a potential problem.

My friend Hugh showed me how to use the oil case box to keep everything clean when removing the oil filter.

Ready for another 50 hours!

More Fixes and More Bad Weather

It’s been almost two weeks since the last flight.  The last one was a good one, though, flying over Arlington for a while, then heading up to Skagit and back.  I’m slowly getting more comfortable venturing away from the home base and flying outside gliding distance of an airport.

No flying since then, though, mostly due to weather.  I’m working on fitting the gear fairings–the wheel pants are done, so next flight will be with those, but I still need to do the upper intersection ones, so no leg fairings for now.

I was also able to fix the electric fuel pump, by replacing an o-ring that was sticking.  Now the pressure doesn’t shoot up to ~80 PSI every time I turn it on.

Lastly, I’m still getting erratic RPM readings above about 2650.  I’ve increased the resistance in the line between the p-lead and the Dynon from 76 to about 100 Kohm, so hopefully that’ll fix it.