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Prop Clocking

JDA_BTR

Well Known Member
About to install the prop and read all the related threads. Any reason to not clock the prop at 9-3 position relative to #1 TDC?
 
The prop can only be installed 2 ways. They are 180 degrees apart. Look at the bushing lengths and recesses in prop hub.
 
Remember to align the crankcase split with the TDC marking on the BACK of the "flywheel", not the mark on the front. As far at 9-3 clocking I think it's another primer wars type issue.
 
Ok I'll look at the flywheel. On the front of the flywheel one hole is marked "O" and it is lined up with a similar "O" on the crankshaft flange. It is the way it was shipped. I'm assuming that is the correct alignment?
 
Ok I'll look at the flywheel. On the front of the flywheel one hole is marked "O" and it is lined up with a similar "O" on the crankshaft flange. It is the way it was shipped. I'm assuming that is the correct alignment?

Never assume anything! Do as Chris says, but make sure that #1 cylinder is at TDC.
 
Beware !

Some extensions are such that you cannot achieve prop alignment with the crank/rods at TDC. The reason is the prop bolts cannot align with crankflange bolts due to space constraints. Mine are 30* OFF. Just FYI, YMMV
 
Are we talking all props need to be clocked correctly? My instructions for my 3 blade Catto didn't say anything about clocking it in any particular place. This may be another thing a non AP builder would not know.
 
As above there are only two possible fittings. The flywheel bushing at ?0? mark is not protruding and so is the bushing 180 from it. The prop mount has 5 recessed spaces and only one bolt without a recess. So the bolt without the recess has to be at the ?0? or 180 from it. So the prop clocking is fixed in the big picture. I?m going to put the bolt with no recess with the ?0? hole. It is the only different hole on the flange marking wise so I?m going to match the marked/different items.
 
As above there are only two possible fittings. The flywheel bushing at ?0? mark is not protruding and so is the bushing 180 from it. The prop mount has 5 recessed spaces and only one bolt without a recess. So the bolt without the recess has to be at the ?0? or 180 from it. So the prop clocking is fixed in the big picture. I?m going to put the bolt with no recess with the ?0? hole. It is the only different hole on the flange marking wise so I?m going to match the marked/different items.
This may be true with your engine and prop. It is not true on all engines and all props.
 
Am I reading the Hartzell install torque table correctly? I think for the four AN4H-4A bolts to the S-603 front spinner bulkhead the torque should be 20-22 ft-lbs but it isn’t explicitly called out like it is for the hub clamping bolts to the spinner plate assembly.
 
Am I reading the Hartzell install torque table correctly? I think for the four AN4H-4A bolts to the S-603 front spinner bulkhead the torque should be 20-22 ft-lbs but it isn?t explicitly called out like it is for the hub clamping bolts to the spinner plate assembly.
I believe the 20-22 ft-lbs is the value for the AN5 bolts that hold the spinner back plate. I would imagine the AN4 bolts for the front plate would take the standard torque value but please let us know if I am incorrect on this.
 
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