Roger Lee Posted June 29, 2010 Report Share Posted June 29, 2010 Hi All, Many have ask "How do I adjust my prop?" This is a fairly easy and quick job. First a few simple tools: (Neuform) a 13mm open end wrench (ratchet style is best), 13 mm 3/8" drive socket and wrench, a 10mm socket, a tape measure, a prop protractor and another level (a 12" long digital torpedo level works well). If you have a Warp Drive you don't need the 10mm, but will need a 7/16" socket and box wrench. First decide how much pitch in degrees you want to add or remove. So let's pick 1 degree to remove for fun. Measure from the tip of the blade an equal distance on each blade and put a mark there i.e. 6". I would take one spark plug out of each cylinder to make rotating the prop easier. You can rotate it with the plugs in, but be gentle so you don't move an already adjusted blade. Loosen the 6 13mm hub bolts/nuts only enough so you can spin them with your fingers. Then facing the prop rotate the prop so you have a blade off to the right. Put the protractor over the tip and pull it back to align with the mark you put on the blade earlier 6" from the tip. The take the other level and set it on top of the blade right next to the protractor. Get the blade level in relation to the floor. Then look at the protractor and move the center until the protractor bubble is level. Now rotate the center the 1 degree with the hash marks on the protractor you want to remove. Make sure the bubble is set so when you turn the prop blade in the proper direction and it moves the 1 degree the bubble will then be in the middle again. To move the blade take the 10mm socket and loosen the 10mm nut/bolt about 1-1.5 turns. The blade should be fairly stiff to turn if you didn't loosen the bolt too much. Loosen the bolt above the blade and below. Do not loosen these too much or when you go to tighten the blade back up it may move on you. So after you have rotated the blade to get the bubble on the protractor in the center then snug the 10mm bolt above and below back up. It only needs to be snug not torqued yet. Do each blade the same way. Then put the protractor and level on each blade one more time to check your work. Now snug up the 6 13mm bolts/nuts. Only snug. Now take the torque wrench and torque the 6 main bolts up in two steps. First torque could be around 120 in/lbs. Then after that is done then torque to final torque of 175 in/lbs. Then use the 10mm socket and torque the 3 10mm head bolts to 120 in/lbs. Then put the protractor and level on one more time to make sure every thing is still where you set it. If you didn't loosen all the bolts up too much then when you re-torque here nothing should have moved. The 6 main bolts are the first to loosen and the first to tighten. Your done. Using this method you should have no problem getting within a .25 degree or less accuracy. Now when your mechanic does this and he isn't sure about the finer points you're ready. Link to comment Share on other sites More sharing options...
Mac Bowden Posted June 29, 2010 Report Share Posted June 29, 2010 The only advice I would add to yours Roger is to remember that us guys with the WarpDrive prop measure from the extreme tip of the blade. Also, I cut a stick to the height of the spinner tip and use that between the floor and the blade tip being adjusted so then each blade is at the same reletaive distance from the floor when measuring/setting the angle. Mac Link to comment Share on other sites More sharing options...
Mac Bowden Posted July 2, 2010 Report Share Posted July 2, 2010 The biggest problem I've had adjusting the prop pitch is loosening the hub bolts enough to be able to move the blade freely but not enough that if you move one the other two blades start jumping about. I made a lever from a couple of bits of 2"x1" with a scissors type hinge at one end and padded it with some black pipe wrap. Now I can leave the hub bolts fairly snug and get plenty of leverage to set the blade angle. It also allows for precision cos the blade doesn't just jump past the angle I want. Mac Link to comment Share on other sites More sharing options...
airhound Posted November 3, 2010 Report Share Posted November 3, 2010 I have a US POC for aftermarket Neuform Prop Decals. Link to comment Share on other sites More sharing options...
Runtoeat Posted February 27, 2011 Report Share Posted February 27, 2011 Hi Roger. Looks like I'm running a little too high rpm on level WOT cruise. The tach indicates 5750 rpm. I'm climbing out at takeoff with 0 flaps and 65 kts. at about 5150 rpm. Any guess how much I need to increase the prop pitch to get back to around 5550 rpm? Shoud I wait for warmer weather to do this since I'm making extra power now in the cold temps? Link to comment Share on other sites More sharing options...
Roger Lee Posted February 27, 2011 Author Report Share Posted February 27, 2011 Hi Dick, Actually you are making a little more power with the cold dense air, but your prop is doing more work in the cold dense air, too. You will need to add approximately 1.25 - 1.5 degrees more pitch to get back down to 5500-5550 rpm WOT. Right now you have a great climb prop setup, but loose out on cruise and fuel economy. We all gain and loose some rpm due to cold winter air verses hot summer air, but I usually don't mess with my prop. I seem to gain and loose approximately 75 rpm between seasons. Link to comment Share on other sites More sharing options...
Runtoeat Posted September 8, 2011 Report Share Posted September 8, 2011 Hi Roger. Just going over some postings during a rainy spell here in Michigan and see you recommend 120 lb-in torque for the four 6mm bolts and and 174 lb-in for the six 8mm bolts in the propellor hub. The standard torque chart in the FD maintenance manual shows 89 lb-in for 6mm and 222 lb-in for 8mm bolts. The torques you show don't agree with the FD chart. Your torque for the 6mm seems high and the 8mm seems low. Looking for where you may have gotten your torques, I cannot find any values for these propellor hub bolts. Are the torques you show published in the FD shop manual for these propellor hub bolts? Link to comment Share on other sites More sharing options...
chanik Posted September 8, 2011 Report Share Posted September 8, 2011 Hmmm, The Neuform manual, which FD typically defers to, shows 10n-m and 27n-m for the M8 and M6 screws which would be 89 and 239 in-lbs respectively. Link to comment Share on other sites More sharing options...
Roger Lee Posted September 8, 2011 Author Report Share Posted September 8, 2011 Hi Dick, 6mm can have anywhere from 40-180 in/ lbs of torque and it depends on the type of metal (i.e. steel or grade 8.8, ect...). Most of the time they are 60-132 in/lbs. Very common is 10NM or 90 in/lbs. Prop bolts are different than a standard every day torque. Typically they are about 12nm or 106 in/lbs, but when you use a Nord Washer on anything the rule of thumb is to increase the bolt torque 10%. So 106 in/lbs + 10 in/lbs is 120 in/lbs (rounded off). So your 90 in/lbs verses 106 in/lbs is only 16 in/lbs different which is negligible. Link to comment Share on other sites More sharing options...
chanik Posted September 8, 2011 Report Share Posted September 8, 2011 But the big M8 bolts should be around 239in-lb, right? Link to comment Share on other sites More sharing options...
Roger Lee Posted September 8, 2011 Author Report Share Posted September 8, 2011 Depending on the prop Mfg the M8's can be 175-260 in/lbs. The 3 blade Sensenich is 240-260 in/lbs. Warp is 175 in/lbs. For the Neuform prop the M6's should be torqued to 10NM or 90 in/lbs + 10% = 100 in/lbs. The M8's are to be torqued to 27NM or 239 in/lbs (no nord washers) http://www.neuform-propellers.com/_downloads/pdf/propellermanual.pdf Link to comment Share on other sites More sharing options...
Runtoeat Posted September 8, 2011 Report Share Posted September 8, 2011 Hi Roger. Thanks for posting the Neuform propellor manual. Exactly what I was looking for. Link to comment Share on other sites More sharing options...
bitten192 Posted September 9, 2011 Report Share Posted September 9, 2011 Hi All, Many have ask "How do I adjust my prop?" This is a fairly easy and quick job. First a few simple tools: (Neuform) a 13mm open end wrench (ratchet style is best), 13 mm 3/8" drive socket and wrench, a 10mm socket, a tape measure, a prop protractor and another level (a 12" long digital torpedo level works well). If you have a Warp Drive you don't need the 10mm, but will need a 7/16" socket and box wrench. First decide how much pitch in degrees you want to add or remove. So let's pick 1 degree to remove for fun. Measure from the tip of the blade an equal distance on each blade and put a mark there i.e. 6". I would take one spark plug out of each cylinder to make rotating the prop easier. You can rotate it with the plugs in, but be gentle so you don't move an already adjusted blade. Loosen the 6 13mm hub bolts/nuts only enough so you can spin them with your fingers. Then facing the prop rotate the prop so you have a blade off to the right. Put the protractor over the tip and pull it back to align with the mark you put on the blade earlier 6" from the tip. The take the other level and set it on top of the blade right next to the protractor. Get the blade level in relation to the floor. Then look at the protractor and move the center until the protractor bubble is level. Now rotate the center the 1 degree with the hash marks on the protractor you want to remove. Make sure the bubble is set so when you turn the prop blade in the proper direction and it moves the 1 degree the bubble will then be in the middle again. To move the blade take the 10mm socket and loosen the 10mm nut/bolt about 1-1.5 turns. The blade should be fairly stiff to turn if you didn't loosen the bolt too much. Loosen the bolt above the blade and below. Do not loosen these too much or when you go to tighten the blade back up it may move on you. So after you have rotated the blade to get the bubble on the protractor in the center then snug the 10mm bolt above and below back up. It only needs to be snug not torqued yet. Do each blade the same way. Then put the protractor and level on each blade one more time to check your work. Now snug up the 6 13mm bolts/nuts. Only snug. Now take the torque wrench and torque the 6 main bolts up in two steps. First torque could be around 120 in/lbs. Then after that is done then torque to final torque of 175 in/lbs. Then use the 10mm socket and torque the 3 10mm head bolts to 120 in/lbs. Then put the protractor and level on one more time to make sure every thing is still where you set it. If you didn't loosen all the bolts up too much then when you re-torque here nothing should have moved. The 6 main bolts are the first to loosen and the first to tighten. Your done. Using this method you should have no problem getting within a .25 degree or less accuracy. Now when your mechanic does this and he isn't sure about the finer points you're ready. Check your work with a digital level ($20-$30 on Amazon)on the tips, fine tune and you can get within ) 0 .1 degree. eb Link to comment Share on other sites More sharing options...
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