Maintenance Schedule
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Every Twenty-Five Hours

1.  Engine check.  See operators hand-book.

2.  Clean gasoline strainer.

3.  Make it a practice to keep the entire airplane clean inside and outside which will greatly facilitate inspection.

4.  Inspect airplane carefully and at the same time use light oil and lubricate moving parts on control system such as aileron end flipper hinges, aileron strut connections, etc.

5.  Keep 8.50 x 10 tires inflated to 25# pressure.

6.  Keep 10" tail wheel tire inflated to 40# pressure.

Every Fifty Hours

1.  Give the airplane a regular twenty-five hour check as outlined on the preceding page.

2.  Check the brake adjustment and correct if needed.

3.  Lubricate the landing and tail wheels.  If the ship has been operated from a dry dusty airport it is advisable to take the wheels off and clean the axles and bearings thoroughly with gasoline to remove all grit and then repack with fresh grease.  Care should be taken to avoid getting too much grease which will collect dirt and get in the brake lining.

4.  Check the oil in oleo shock struts as described elsewhere in this manual.

5.  Remove metal pan at the bottom of the fuselage just behind the motor cowling and check control cables and parts.  If the ship has been flown from a dry, dusty airport, and these controls are covered with grit, clean them thoroughly with kerosene or gasoline removing all grit and then lubricate with fresh grease.  Lubricate all control cables, pulleys, etc., with graphite grease.  Where cables go around the pulleys check to make sure they have not frayed.  This can easily be detected by moving the hand carefully over the control cables.  If they are frayed there will be sharp ends of wire sticking out at the frayed points.

6.  Lubricate tail wheel fork support and tail wheel shock strut both of which are supplied with a zerk fitting, the fitting on the shock strut being just inside the fuselage.  This fitting can be reached through the inspection opening at the rear of the fuselage immediately in front of the rudder post.

7.  If the stabilizer works hard, with tail cowl removed, clean threads on long adjustment thoroughly, and then lubricate with heavy oil or cup grease.  If stabilizer cable is slipping there is an adjustment at the rear baggage compartment to take up play in the stabilizer cable.  Tighten until slipping is prevented.

8.  Inspect the fire extinguisher and refill if necessary.  See instructions on page 7.

9.  Carefully inspect the entire ship removing inspection plates where necessary.

Every Two Hundred Hours

1.  Give airplane a regular fifty hour check as outlined above.

2.  Check engine carefully.  A major overhaul is recommended each 400 hours.

3.  Raise tail of airplane and support with a horse or something of that nature at the tail post, make sure that cover is protected with a pad.  Remove top tail cowl and cowling which is screwed to the bottom of fuselage to keep dirt out.  Now inspect carefully the tail wheel mechanism for wear and play.  It is suggested that the entire mechanism be removed and cleaned thoroughly and lubricated again with fresh grease.  Bushings for the tail wheel support and additional rubber discs for the tail wheel shock strut can be obtained from the factory if needed.

4.  Remove weight from one side of the landing gear at a time so that the wheels can be tested for play in the splined section of the oleo struts.  The allowable play is movement of 1/2 inch from extreme toe in position to extreme toe out position on each wheel at outer circumference of tire.  When play exceeds this install new bronze splined bushings.

5.  Examine propeller carefully and whether wood or metal prop it should occasionally be checked for balance, leading edge repaired and generally reconditioned.  There are numerous metal propeller repair stations fitted to do this work, or if a wood propeller is used, it is suggested that it be returned to the Hartzell Factory for reconditioning.

6.  Inspect the rear oval and top windows in the cabin as pyralin is used on these surfaces in place of shatter proof glass.  If the pyralin is beginning to check or turn yellow its replacement is advised, for when it gets in this condition, it not only cuts down visibility, but also gets stiff and is likely to crack and break with the least bump.

On request, printed Inspection forms covering above maintenance in detail can be obtained from the Waco Aircraft Company.

Assembly of the Brake Mechanism

After the front undercarriage has been properly bolted into place, the Bowden casings which house the brake cables and are protruding from the side of the fuselage should be threaded into the shock strut fairing and through the fairlead tubing at the bottom.  The break arms should then be set on the splined shaft approximately perpendicular to the line of pull of the cable.  Care should also be taken to prevent the cable fittings from moving high enough to touch the end of the cable casing.

Brake System Adjustment

The first item of adjustment of course, is properly locating the brake lever on the splined shaft.  Then place the cable around the pulley on the lever end back through the bolt provided on the cable fairlead.  The cable should be pulled just taut enough so that with one of the rudder pedals at full forward position, the wheel for that side can just be turned by hand.  Each wheel can be taken up individually by loosening and reclamping the cable in a new position, or tightening of the system to both wheels can be done by the turnbuckle link alongside the control column which is accessible through a door in the bottom of the fuselage.  As a further check on the equalization, pull the hand level back until brakes are locked and see if the rudder pedals stay in neutral and that by pushing on one pedal and then the other, the pedal pressures should "feel" equal.  The Autofan Brakes are produced with no adjustment whatever and changes in the cable tension will automatically take up wear in the lining.

Flap System

The flap system as used on the Waco Custom Cabins is of the vacuum cylinder type using the manifold depression.  As ships leave the factory, flaps are very carefully adjusted so that each side will open and close simultaneously.

Every twenty-five hours inspect the operating mechanism and if necessary grease the rail thoroughly and lubricate all moving parts with light oil.  The most likely source of trouble will probably be due to leaking in the lines or worn out leathers in the piston.  This normally, however, will not occur in the first 500 hours.

At the bottom of each cylinder front castings will be found a small hole for venting air ahead of the piston in retracting and this should be inspected occasionally for clogging up with dirt.  It is recommended that you do not attempt to synchronize the timing, if for any reason this should change, without first consulting the Waco Factory.

Care of the NACA Cowl

Whenever the engine ring cowl is removed the felts which bear against the cylinder rocker box and also the leathers in the support brackets should be inspected and when worn sufficiently to allow the cowl to be loose, they should be replaced by new felts and leathers of the same dimensions.  Needless to say, the cable around the ring cowl should be taut at all times.

Stabilizer Adjustment

Whenever the stabilizer adjustment crank on the control column can be turned without movement of the stabilizer, the control cable should be tightened.  Access for this adjustment is provided through the rear lining of the baggage compartment.  Adjustment should be made promptly to avoid wear due to slippage in the pulleys.