RV-8 and the 2023 Condition Inspection Pt. 4
Updated: Apr 9
The weekend of 4/8/23 - 4/9/23 saw me getting a lot closer to being finished. When I left off last weekend all I had left to do was to reinstall the heat muff and inspect / grease the propeller.
I was a little afraid at first because it is usually a real fight to get the heat muff on and the SCAT tubes connected. This time, the muff went on fairly easily, but the SCAT tubes went on very easily, to the point that I had to double check that they were actually on correctly. They were. More importantly, this time I remembered to install the 2 cotter pins that capture the hinge pin that holds the muff on the exhaust pipe. I had apparently forgotten to do that the last time I had it off and one day on my post flight I found the hinge pin backed about halfway out of the hinge. While it was possible to get it back in and get a cotter pin in it through the cooling air exit at the bottom of the cowl, it was not easy or fun.
The next simple step, or at least one that I had always thought of as a simple step was to grease the propeller. The Hartzell instruction manual specifically states: "Pump 1 fl. oz. (30ml) grease into the fitting located nearest the leading edge of the blade ..., or until grease emerges from the hole where the fitting was removed - whichever comes first." That is followed by a note that says "1 fl. oz. is approximately 6 pumps with a hand-operated grease gun."
I had always taken that statement at face value and never put in more than 6 pumps. In fact, after reading about problems from props with too much grease I used even less. A while back there was a post on Vansairforce.net (VAF) stating that 1 fl. oz. is much more than 6 pumps on any grease gun the poster had ever tried. In fact it took a lot more to get one ounce. Now I was baffled. How much grease do I put in this thing. Too much is not good, but too little may be problematic also.
I came up with my own test for my gun. I took a 1 fl. oz. measuring cup and, just for giggles a digital scale to see if there was a big difference between 1 fl. oz. and one regular ounce.
I first tried 10 pumps and that resulted in a lot less than I had inspected. The picture above represents 20 pumps from my grease gun. It weighs it at .4 oz. and looks like maybe about 1/2 fl. oz. I didn't want to try to pack it in there to get a more accurate reading, this gave me what I wanted to know.
I went to the propeller and pulled out the first grease fitting and put 10 pumps into the other fitting. Nothing came out of the empty fitting hole. From there, I moved to the other blade and removed the proper fitting on that side. After 15 pumps, with nothing coming out of the other hole, I went back to the first side and there was a big hunk of grease that came out of that first hole. I had not expected that. The wording of the instructions led me to believe that any outflow would come from the same side.
I cleaned that up and then went back to the first side and put in another 5 pumps, for a total of 15 per side. There was now a little bit of grease coming out of the second hole.
After cleaning up the old grease, I put the removed fittings back on, put caps on them and reinstalled the spinner.
The last thing I did, for the firewall forward section, was look at some of the items mounted to the firewall, and to my great surprise, the bolts holding parts of the Christen inverted oil system to the firewall were loose. I opened up the forward baggage door and tightened them.
Now it was time to embark on another of my least favorite parts of the inspection, inside the fuselage. It is just very cramped and difficult to work in there. The first order of business was to remove the rear baggage panels so I could inspect the battery and lubricate the bellcrank for the elevator push / pull tube. "It's only 19 screws, how hard can it be?" Pretty hard. The screws aren't too bad to get out, except that there is no room to move and even with the tail jacked up, it is still not level and I have to fight falling back there. It is difficult to get into a position to use both hands, so I usually have to prop myself up with one and try to work with the other.
Working the bottom panel out is also a pain as it is tapered and fits rather snugly so it is difficult to maneuver out of the way.
I had just replaced the battery last year, so fortunately, it is in good shape. I recently found that a small syringe is the best tool for installing lubricant (LPS 2) on the various control bearings and bushings and it worked well here too.
With the rear fuselage done it was time to move forward. I started by removing the two forward floor panels. With these two out, it is possible to lubricate the push / pull tubes going to the ailerons.
There isn't a lot more to see by removing the big floor panel with the foot wells attached, so I only do it every other year. There are a couple of antenna connections there and the electric aileron trim servo. It's pretty easy to tell if those are working. This panel is also a huge pain to get in and out, again, hence the every other year or so.
Once that was inspected I put the big floor panel back in. The next simple step was to inspect and lubricate the flap push rods where they attach to the flap torque tube. The left side has the actuator and the right side just the push rod. They are behind panels in the back seat that are also a trifle difficult to remove. So much so, that I don't actually remove them, I just get to where I can open the front edge to look in there and lubricate the upper flap rod end.
The right side has only a push rod and so, is a little easier to access to lubricate.
The astute observer will note that this airplane still has the original round push rods as opposed to the newer, beefier hexagonal push rods. The newer ones are supposed to be sturdier, but I think that as long as I obey the flap actuating airspeeds, there shouldn't be a problem.
The last thing to do for the day is to test the ELT. For the most part it is pretty easy to test, but the G-Switch test is a little difficult to do without much room to move the thing about, but I was able to do it and it does work, so I am good for another year.
Sunday afternoon I finished inspecting the forward cockpit area and lubing the stick and rudder pedals. It was pretty dirty on the floor of the front seat, so I managed to get the vacuum in there so I could clean it up.
The last thing I did for the day was to cut open the oil filter. I was gladdened to once again see relatively few carbon bits in it and no metal.
That just about wraps up the 2023 Condition inspection, just a few housekeeping things left to do and then put everything back together and take it out to make sure that it still flies.