Pulled The Trigger

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kwanjangnihm
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Re: Pulled The Trigger

Postby kwanjangnihm » Sun Aug 02, 2015 5:15 pm

John Fenner wrote:You're welcome, O-540 crank cracked longitudinally at flange and oil leak at seal area. O-520 sheared off all crank drive gear bolts


John I am not doubting your knowledge on this, just want some more input. Does this issue happen when the 3 blade setup is balanced and dialed in as it should be, or does it happen when someone haphazardly bolts a 3 blade on a 540? Or is it always destined to happen?
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digginfool
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Re: Pulled The Trigger

Postby digginfool » Sun Aug 02, 2015 6:31 pm

While there may be multiple examples of three blade props on aircraft, they are continuously variable pitch. I would have to guess that the fixed pitch is what sets up the harmonics. I know with my gearbox, I adjust engine speed up or down to eliminate harmonics.
Last edited by digginfool on Mon Aug 03, 2015 8:16 am, edited 1 time in total.
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Re: Pulled The Trigger

Postby lariat » Sun Aug 02, 2015 8:17 pm

John Fenner wrote:Do not run 3 blades on 6 cylinder engines, the harmonics are crankshaft breakers.


I wonder why no prop manufacturers say anything about this? Everyone that I am aware of makes a 3 blade specifically for 6 cylinders.

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BUSHHOG85
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Re: Pulled The Trigger

Postby BUSHHOG85 » Sun Aug 02, 2015 9:04 pm

John Fenner wrote:You're welcome, O-540 crank cracked longitudinally at flange and oil leak at seal area. O-520 sheared off all crank drive gear bolts

How did you determine the prop was the cause? There's more boats than you could count running 3 blades with 100's of hours with no troubles
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digginfool
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Re: Pulled The Trigger

Postby digginfool » Wed Sep 09, 2015 6:58 pm

Finally done. Rode all weekend on KCOL and the boat was amazing. Cruised well at just off idle, didn't hesitate to move anytime we stopped, even in the bright green gas that had my DB floored to get moving. On Saturday, we rode 72 miles on 18 gallons. Gotta love it! Went with a 72" Excalibur prop. Ended up doing a full overhaul on the motor; new rod and main bearings, 10:1 pistons, Phase 3 cam, rebuilt cylinders, Norman Clay headers. It was a great decision to go this route.
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lilly-Pad
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Re: Pulled The Trigger

Postby lilly-Pad » Wed Sep 09, 2015 9:52 pm

looking good Digging :cheers: you coming to the Poker run with it , kind of like taking it back to its roots
12 ft Don Davis / 0470 conv / 68 NGQ , A.A.O.F member

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digginfool
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Re: Pulled The Trigger

Postby digginfool » Wed Sep 09, 2015 11:03 pm

Haven't decided yet. I want to go but have a fuel pump issue plys no place to stay if I did, except my truck.
“When plunder becomes a way of life for a group of men living together in society, they create for themselves in the course of time a legal system that authorizes it and a moral code that glorifies it” - Bastiat

mwood7800
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Re: Pulled The Trigger

Postby mwood7800 » Thu Sep 10, 2015 8:30 am

I'm happy with a 3 blade on my 540. Lot smoother than a 2 blade. I had a 6 warp before the 3. Now 3 years with the 3. I liked the warp but do not miss adjusting the all those blades. If you had problems from a 3 blade did you have the crank counter weights installed?

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Re: Pulled The Trigger

Postby One Eyed Gator » Thu Sep 10, 2015 9:01 am

Does it float any different with 6 cyl on it?

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HuntingBigun
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Re: Pulled The Trigger

Postby HuntingBigun » Thu Sep 10, 2015 9:05 am

digginfool wrote:Finally done. Rode all weekend on KCOL and the boat was amazing. Cruised well at just off idle, didn't hesitate to move anytime we stopped, even in the bright green gas that had my DB floored to get moving. On Saturday, we rode 72 miles on 18 gallons. Gotta love it! Went with a 72" Excalibur prop. Ended up doing a full overhaul on the motor; new rod and main bearings, 10:1 pistons, Phase 3 cam, rebuilt cylinders, Norman Clay headers. It was a great decision to go this route.



Looks great and good seeing ya again as well, good luck on the gator killing
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digginfool
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Re: Pulled The Trigger

Postby digginfool » Thu Sep 10, 2015 9:09 am

One Eyed Gator wrote:Does it float any different with 6 cyl on it?


It sits a little lower in the water but not by much. The 540-E weighs about 100 lbs. more than the 320 H2AD I had on it before. The most notable difference (aside from the big power increase) is how much more loose the boat handles. It definitely slides a whole lot more around corners and requires very positive input to keep it going where you want it to go. I would imagine that's mostly due to the additional mass in the ass. :lol:
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