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Pacer props

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I know exactly what you mean. I attempted to hand prop my old Pacer once. I got it primed, put my hands on the blade, and quit right there. It was too awkward for me to even try. It's nothing like the Champ I learned on, and I didn't see any sense in dirtying up a nice clean plane.

Speaking of awkward, I watched a guy hand prop a radial solo a while ago. The prop would be roughly at a 2&7 position and he would spin it using kind of an underhanded twisting/wrenching movement then bust-ass around the wing to goose the throttle before it died. THAT looked awkward.

I like the option of being able to hand prop without goring myself. So, at the next annual I asked the mechanic if it would be a problem to reposition the prop to a more suitable position for hand proping. He looked into it and couldn't find a reason why not, so he repositioned it for me. Luckily, with a new battery I never needed to use it.

Is that a shorthair or a wirehair in your avatar? Looks like I can see a five o'clock shadow.
JRStripe offline
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I had two Tripacers before getting the Maule and neither one of the props stopped straight up and down. Take the prop off and rotate it to the position you want it to stop at, if I remember correctly. :roll:
iceman offline
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It's my understanding that the prop is indexed to a certain spot for engine balancing reasons. Moving the prop to a different location relative to the crankshaft could cause excessive vibration, harmonics and other nasty stuff. I've never noticed that pacers stopped with their prop at 12/6 tho....the Colt that I'm flying now stops at 2/8. My .o2$...no change necessary :)
NCBearhawk offline
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I'm not a mechanic but I was always careful to put the prop back at the same position each time but another A&P told me it didn't matter as long as the prop was balanced in that position. Anyway I never noticed any increased vibration at different positions. After all it is a Tripacer, and everything vibrates anyway, along with great ventilation. I loved the planes though and they took me all over Idaho on vacations. Keep the battery up to charge and you won't have to worry about hand proping. :)
iceman offline
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Many Pacers (the ones with the O-320 150 hp engine) have the same engine, and same prop. They should be indexed at 10/4, as viewed from the front. This isn't critical for vibration or anything else, though, but it is the best indexing for hand propping.

My guess is some dip took the prop off and just stuck it back on without indexing it.

The Husky prop is a constant speed prop, and the engine is an O-360. The O-360 has a lot of vibration issues, and the re-indexing of the prop to 12/6 was an attempt by the factory to smooth them out. It didn't do squat, frankly. I've re-indexed a couple of Husky props to 10/4, based on a service bulletin issued by Lycoming. It requires some new bushings, and is more work than re-indexing the fixed pitch club on a Pacer, but is still not that big a deal.

BUT, first and foremost, NO MATTER what kind of prop you have, get the rotating assembly dynamically balanced. You'll significantly reduce vibration and improve longevity of components.

MTV
mtv offline
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Regarding balancing props and re-indexing them and vibration associated etc. When the prop on an airplane is dynamically balanced, your actually balancing the whole rotating mass, at least to a 1 to 1 to crankshaft revolutions anyway. You may in fact be unbalancing the prop to achieve a low vibration level of the engine. This is why it's always a good idea to put it back on in the same position it came off of, but it can be balanced in any position that it can be installed. There's no Vodoo here, as long as there isn't any alignment bushings or anything to prevent you from re-indexing the prop, go for it and if it picks up a vibe, have it balanced.
a64pilot offline
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just for the record I checked three Tripacers today at Gillespie and all were at 10-4 position which is where both of mine were and when I took the prop off to change to my climb prop the climb prop went on exactly the same. ( I used a climb prop when I went to Idaho) I agree, someone probably just stuck it back on where they thought it should be.
iceman offline
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