Long-EZ propeller mounting and care

Aircraft Propeller mounting and care

by Al Hodges

MOUNTING PROCEDURE: Apply a light coat of beeswax or paraffin wax to drive lugs and center spud extension. Care should be taken to keep propeller hub face parallel to the flange face while tightening the bolts. DRIVE LUGS ARE A MUST!

TORQUE: Torque to 250 inch pounds and check after the first flight is completed. Recheck every 10 hours until completion of 50 hours of flight time on your new prop. Then, check torque every 25 hours.

TRACKING: Carefully track your propeller. Get it perfect. Do not settle for 1/16" being close enough. Tighten all bolts to 250 inch pounds. Check track. Back off the three bolts on one blade and continue to tighten other three up to 350 inch pounds, each time tightening the other three to 250 inch pounds until it tracks perfectly. You will be happy with the smoothness you will gain. Place a stick on wing held in place with a bean (shot) bag. Align stick one inch from end of prop. BE SURE MAGS ARE OFF AND PROP TORQUED TO 250 INCH POUNDS. Rotate prop to determine if prop to stick gap is equal and track is equal. If not tracking exactly, a slight variation can be corrected with differential torque on lugs until in line. If track is too uneven, a piece of folder stock may be used as a shim between prop flange and prop face to even up track.

UNEVEN GAP: Check if crank flange is bent. Remove prop, rotate 180 degrees, then replace prop. If opposite end of prop is now farthest from stick, you have a bent crankshaft or bent flange. Both are expensive to correct. When finished, be sure proper torque (250 inch pounds) is maintained on all lugs.

MOISTURE: Always leave a wood prop in a horizontal position when you park your plane. It draws moisture to the bottom blade if vertical and will vibrate until weight is equalized. If you do not fly for a long period, rotate the prop 180 degrees occasionally.

PROPELLER CARE: Automotive paste waxes can be used to clean the finish. No other care is necessary. IT IS ESSENTIAL THE CENTER HOLE OF THE PROP BE COVERED. If you are not using a spinner, use an aluminum plate under your crush plate or moisture can soak in the center hole and damage the hub area. (MAH comment: Since 1992, I have used a wine bottle cork in the center hole with excellent results. It weighs less than a plate. If aircraft is parked on ramp, sun and weather will take their toll. Cover the prop to protect from sun damage while leaving room for ventilation.)

ROCK DAMAGE: Light impact damage can be repaired with two part epoxy filler available in tubes. Always carry JB Weld or a Duro epoxy kit. Fill small chip holes and small voids, clamp with a rubber band until cured, and sand the hardened epoxy to fit contour. Although the epoxy is very dense, the amount of imbalance resulting from small repairs is negligible.

PLASTIC LEADING EDGE: This type of leading edge is effective in preventing small rock damage, and if damaged, is easy to repair with JB Weld. However, rain and hail can cause serious wood damage. When entering rain, decrease the RPM as much as possible because rain can damage the wood behind the plastic. At idle, little damage, if any, will occur because the prop is not creating thrust or drag. In rain, hail, sleet or snow, throttle back and save your prop.

PAINTING OUTER TIPS: If you wish to paint the outer three or four inches of the tips, make sure an equal amount of paint is applied on each side to maintain the balance of your prop.

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