Okay, time to remove the prop on the #3 engine. The most difficult thing about this whole project was to find all of our stinkin' tools here in the hangar to complete the task at hand.
Boy, I've really got to get organized around here.
Anyway, step one is to remove the dome cap retaining clip, followed by the removal of the dome cap itself. Be sure to have a bucket, drum, or whatever underneath the prop, as it's likely going to dump a little oil (however, on conventional gear [taildragger] aircraft, the oil will typically be at the rear of the dome and won't make quite the mess at this point). I try to spoon out the majority of oil at this level, so that it's not constantly dripping. Then I put on the dome handle to make it easier to remove and whatnot.....
The next step is to cut the safety wire from the dome nut lock, followed by the removal of the lock itself. As you can see, this is a special little screw, so it's important not to lose it......
Next, you just slide the dome nut wrench over the dome (duct tape on the inside of the wrench helps assure that you won't scratch the dome during it's use). Then, while putting pressure on one side of the wrench, you give it a good whack on the other side with a fairly heavy hammer. After it's broken loose, it should simply unscrew with ease. It's a good idea to hang on to the dome when getting close to the end of the threads while unscrewing, however, there are some dowel pins that are typically long enough to hold the dome in place. But I still always get nervous about dropping the dome, so it's just good practice to be careful here.........
And then I carefully ease the dome forward, while keeping it on it's dowel pins. You don't want the dome to rest on the distributor shaft inside. I will typically allow some time to let the majority of oil drain before removing the dome completely......
When removing the dome, be mindful that it's heavy! This one weighs between 40 and 50 pounds (depending on how much oil is left in it), and the dome on a
real propeller, like on the B-29, is in the neighborhood of 80-90 pounds!
Don't allow it to drop down on the distributor shaft as it slides off of it's dowel pins. And be aware that it's going to be an oily mess (stinkin' Hamilton Standard props
) when lowering from the airplane. I always try to set it down in a bucket, or in this case, the oil drum funnel. This allows it to completely drain while you are working on other things. Also, there will likely be at least one or more brass shims beneath the dome. Make sure that you retain those shims, as it is crucial that they go back under the dome upon reassembly. These are put in place by the prop shop when they set up the backlash on the gears of the dome and prop blades. The shim stayed with the dome upon removal this time.........
The now exposed "guts" of the propeller are going to continue to drip oil now. What I typically do to get this process overwith quickly, is to spoon out as much oil as I can. I know a lot of the "old timers" roll their eyes at me when they see me worrying so much about making a mess...and perhaps if I were in more of a hurry, I'd not be so concerned about it. However, in this case I'm just taking my time and it's much nicer to work in a "not-so-oily" environment.........
Once you've gotten the majority of oil drippage stopped, you can go ahead and remove the distributor shaft (also known as the "stalk") and retaining nut lock. If you don't take this locking ring/pin out before trying to remove the distributor shaft, you'll start tearing the locking teeth out of it. It's not unusual to see a stalk come out with some broken or missing locking teeth. The removal of this lock is simple. Just slip a hook (or small screwdriver) under the ring and pry it out of it's groove. The rest of it will just pull right out with ease.........
Once the lock is out, you can put the special wrench on the distributor shaft and give it a little whack with the hammer. This too, should break loose fairly easily and should then unscrew quite simply by hand. If it doesn't...you've forgotten to remove the lock! There will be a copper gasket beneath the stalk. It's a good idea to go ahead and remove it at this time as well.......
And just as I mentioned before, this stalk has had one of it's locking teeth displaced from a previous attempt to remove it with the lock still installed. This isn't anything to be too concerned about, as long as this damaged tooth isn't used when locking the stalk back in place during reassembly.........
Okay, so now that everything else is out of the way, it's time to loosen the prop retaining nut. This is what actually holds the prop to the engine. It too, is a fairly simple process, but requires two people (minimum). First, you place the retaining nut tool over the nut. Then you find someone who's not doing anything (Mark is always a good source for that around here
). The first thing your helper can do is to place a ladder under the lowest prop blade, to hold it in place while breaking the nut loose. It's obviously important to place a rag, or other form of padding between the blade and the ladder..........
Next, you get your helper to hand you one end of the prop bar. Place it in the tool and have your helper put pressure on it on the other end. While he's got a pretty substantial amount of force on the bar, you can give your end of it a good whack or two with the hammer. It should break loose eventually.....
Now, initially broken loose, the retaining nut will be quite easy to turn for about a rotation or so. However, once the backlash tightens up against the prop, it'll take a bit of force to "pop" the prop loose from the cone it rests on. Once the prop breaks loose from the engine, you should be able to run the retaining nut the remainder of the way loose with placing a pry bar or similar through the retaining nut tool. You can also watch the back of the prop to see that it is indeed getting further away from the engine.........
And finally, once you have the retaining nut completely loose, just sling up the upper blades to the forklift and ease the prop off the airplane. Once it was sitting on the floor, I decided to go ahead and put the dome back on temporarily, just to keep the guts of the prop covered up. Nothing to it.
...........
I'm removing the engine cowling and other odds and ends next, so stay tuned...
Gary
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This morning, I ran the engine up one more time, just to warm the oil up a bit. This is cheating a little, since the warm oil tends to drain faster than cold oil and I just didn't feel like working around draining oil all day.
..........
But nonetheless, here's the upper section after removal.......
