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2 Blade Prop Clocking


Steve 1

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My Long Ez always has one blade with some exhause residue. Does anyone know the correct method of clocking so that BOTH blades are out ouf the exhaust pulses? I have done it the same way for years and the engine most always stops with the prop at 10 and 4 so I thought I had it right.

Thanks in advance,

Steve in K Falls

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10-4 is great for hand propping.

 

7 - 2 will give you the minimum exhaust inpingment on the prop

 

Set your crank at #1 TDC, then, viewed from behind, the prop should be at 7 - 2.

 

Waiter

F16 performance on a Piper Cub budget

LongEZ, 160hp, MT CS Prop, Downdraft cooling, Full retract

visit: www.iflyez.com

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FWIW, when clocked at the 2 : 7 position with # 01 @ TDC, you will miss the pulse, but the residue will always be there to a greater or lesser extent ... it's in the swirling air.

 

The pulse itself on the other hand will kill a prop in the not too distant future ...

my in cowl exhausts are 2" away from the prop and nailed it within the first hour, then I learned about the clocking. :(

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I live in my own little world! but its OK, they know me here!

Chris Van Hoof, Johannesburg, South Africa operate from FASY (Baragwanath)

Cozy Mk IV, ZU-CZZ, IO-360 (200hp) 70x80 prop

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I seem to recall that Mike Melville put heat sensitive tape on his prop to measure the temperature and concluded that; properly clocked; the prop stayed well below any danger zone. I agree that the prop gets a lot of dirty air being at the aft end of the plane and avoiding the pulse is a good idea. I'm fabricating another prop and have the opportunity to drill it so that I can clock it at the preferred 1 and 7. I'm also going to fabricate a three blade prop. Anyone know of the preferred clocking?

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On the three blade, your screwed!

 

I one position, you'll hit one blade very heavy, in the other position, you'll get two blades, but not as bad.

 

With #1 TDC I have one blade straight up and two blades down.

 

Waiter

F16 performance on a Piper Cub budget

LongEZ, 160hp, MT CS Prop, Downdraft cooling, Full retract

visit: www.iflyez.com

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mm and a 4 blade? I have a MT 4 blade on my newest toy (a cosy classic) the MT is white and the soot looks especially nasty on it, any idea how I could clock that one (classic 4 exhaust end of cowling)??

wolf.

Cosy Classic flying (ex LX-ACE)

Varieze N39JC rebuilding

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mm and a 4 blade? I have a MT 4 blade on my newest toy (a cosy classic) the MT is white and the soot looks especially nasty on it, any idea how I could clock that one (classic 4 exhaust end of cowling)??

wolf.

Anything with that may blades will always get some of the blades very dirty. paint it black. why did you go to a four blade prop?

Evolultion Eze RG -a two place side by side-200 Knots on 200 HP. A&P / pilot for over 30 years

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Anything with that may blades will always get some of the blades very dirty. paint it black. why did you go to a four blade prop?

I did get the whole plane and the prop was convieniently attached to the rear.:D

No ernest the 4 blade variable prop from MT gives a supersmooth ride, especially compared to the wood fixed pitch I had on my Long, talked with the builder of my Cosy and he wanted the 3 but got a good deal on the 4 blade.

 

My Wife never liked the Long, not enough space, no view, felt seasick.

The Cosy was the oposit, she loves it, and does not even get motion sickness, (If Mama is happy, is everybody hapy) YES YES YES..

 

wolf

Cosy Classic flying (ex LX-ACE)

Varieze N39JC rebuilding

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