Why are my wheel pant mounting plates cracked?
Wheel pant mounting plates commonly crack around the axle. If any cracks are present, they should be replaced. The cracks are caused by wheel pant vibration. Assure that the wheel pant axle bolts are tight. Proper wheel balance will lessen wheel pant vibration. McFarlane's wheel balancers can help solve this problem.
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Is there any special inspection process needed?
No. Preflight and annual inspections are no different than with a metal prop.
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Why is PROP GUARD clear?
Being clear allows you to see through PROP GUARD to inspect the propeller.
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Why should every mechanic have an Alternator Drive Coupling Tool?
The coupling provides a shear point, protecting the engine from damage should the alternator fail. However, it is imperative that the coupling be installed properly and inspected every 500 hours or any time that the alternator is removed from the aircraft. This critical component has been the subject of several Service Bulletins (SBs) and Special Airworthiness Information Bulletins (SAIBs) because an out-of-tolerance or improperly installed coupling can lead to catastrophic engine failure. The lack of specialized tools to perform these tasks has made compliance difficult for many shops, increasing the risk that these critical inspections are not being performed in the field. In addition, alternator coupling slippage is a frequent cause of low alternator output. Without the tools to properly inspect the coupling, these failures are often misdiagnosed as a failure of the alternator, resulting in wasted time and money for both shops and owners.
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Does an oil change just include draining the hot oil, changing and inspecting the filter, and refill?
No. The pilot or mechanic should always review the manual for proper procedures. For example, on most engines an inspection of the oil pan's suction screen is recommended at each oil change. Although one may rarely find anything during a maintenance check, it's not worth taking the risk.
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What is the difference between light and medium? How do you choose which one?
The light weight is a flexible compound for use as a joint sealing compound, caulking compound, corrosive preventative, lubricant, threaded joint dressing, insulating material, or filler with packing.
The medium weight seals with a gasket or as a gasket. Seals pumps, tanks, pressed plates, covers, pans, etc. for pipe threads and imperfect or uneven surfaces.
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How do I know if my universal joint needs to be replaced?
A universal joint attaches to each control yoke shaft behind the instrument panel. Universal joints are very precision. Replacement of the universal joint is required if any free motion or rust around the joint pivots is detected or if the joint fails inspection required by the Piper AD 2010-15-10.
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How do I repair a damaged cowl before installing Cowl Saver?
There are several ways of repairing worn cowl surfaces. Epoxy fill is sometimes used for minor wear, or flush or double flush riveted aluminum doubler plates can be formed and installed over the damage. McFarlane has a high temperature (400deg F) sandable two part epoxy with an aluminum filler that works well for filling minor cowl skin defects; please see P/N 20 GLUE KIT. Consult with your A&P mechanic for the best repair solution for your aircraft.
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How do I get all the parts lined up and the bolt in place at the aft roller locations while working in the small flap hole?
We sell tool P/N 970 to facilitate the installation of the aft rollers and make the installation easier and simplified for this hard to reach location.
The handle of the tool makes access to the bolt hole in the small inspection opening easy. The pointed tool allows you to align the parts and easily insert the tool in the bolt hole. The next step is to push the tool back out of the hole with the bolt.
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Why is there discoloration on my brake bleeder valve?
The fittings are covered with a special cadmium plating with a phosphate coating. The coating provides the best possible corrosion protection for use with magnesium brake castings in a wet environment. The white deposits are phosphate crystals that form from a phosphate sealing process which helps prevent corrosion when installed in magnesium alloy. The white deposits are not corrosion and will not harm the installation. If needed to reduce tightness during installation, the crystals can be softened using plain hot water and a tooth brush. Use the required thread sealants as specified by the appropriate aircraft service manuals.
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What is in the McFarlane flap roller kits?
Flap Roller Kits contain all of the rollers needed to complete one aircraft. Flap Roller Upgrade Kits include all of the components, forward wear washers (P/N MCS1450-3S10-032), aft service kit (P/N MCSK100), and hardware needed to replace the flap rollers and hardware associated with the rollers, along with Cessna SEB95-3 Rev. 1 for instructions to inspect flap support arms for wear.
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What else can cause poor steering response besides the steering rods?
We have seen torn brackets on the rudder bar torque tube cause lose of rudder motion and steering movement. The earlier Cessna airplanes had less reinforcing of the rudder bar torque tubes where the steering rod attachment brackets are welded on than the later model airplanes. An overload of rudder pedal pressure or prior nose gear damage can cause failure of the bracket attachment. Inspect all of the rudder and steering system when poor steering authority is detected.
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What colors are available
Standard colors:
- White (RAL9016)
- Red (RAL3020)
- Gray (RAL7005)
- Flat or Shiny Black (RAL9005)
- Yellow (RAL1021)
- Blue (RAL5010)
Flat Black with white tips is the most popular because those colors do not clash with any other colors. They are also the most durable paint colors. Other custom colors may be ordered for an up-charge, but that could delay delivery for several weeks. MT prop blades and spinners may be painted with common materials by any prop shop.
The MT Spinner domes are Kevlar and will never crack. They are finished in white or flat black paint. An optional Chrome plating may be selected on limited types of models.
The Bonanza/C210/C206 props are Diamond Silver with B/WB tips.
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I have just installed my new Fuel Pump and my engine will not start. Why?
A common cause for this problem is fuel starvation due to improper installation of the fuel pump. Make sure that the fuel lines are not crossed; that is, the inlet line should be connected to the inlet side of the pump (marked “IN” on the top of the port) and the outlet line should be attached to the fuel pump outlet port. Fuel should be present at the inlet side of the fuel pump.
Improper installation of the fuel pump may result in a misalignment of the operating lever with the operating plunger in the accessory case. If so, there will be no movement of the lever and no pumping motion to provide fuel flow. If misalignment is found upon removal of the pump, the lever is probably damaged or broken. If misalignment of the operating lever has occurred, it will require inspection and repair by a qualified technician.
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How important are baffles and seals to cylinder temperature?
Baffles and seals are critical to keeping an engine cool, yet they’re often overlooked. When you’re flying, air enters the cowling and creates static pressure above the engine. This pressure then forces cool air down through your cylinders and oil cooler to the lower pressure areas below and behind the engine. From there, the air travels out through the flaps or other flaring openings.
What’s important to consider is that there is only a given amount of air coming in through the cowling at any given time. If your baffles are broken or misshaped, the amount of air going past a particular cylinder or area will increase. And if you increase airflow in one area, then airflow past other cylinders and the oil cooler will decrease, leading to higher temperatures in some parts of the engine than others.
Seals can create similar problems. If your seals aren’t in good condition or aren’t properly adjusted, they’ll allow air to bleed out. Which can reduce static pressure and cooling. So what can you do? Whenever you install a new engine, always have the baffles checked. Also, as part of your periodic inspections, check all the seals for fit and condition.
If the seals aren’t soft and pliable, replace them. Do this if your oil or cylinder temperatures seem abnormally high as well. Also check how the seals fit against the cowling. If there are noticeable gaps, adjust the seals to reduce air leakage. Be sure to inspect the holes at the rear of the cowling for excessive leakage. If your cylinder heads still run hot, it may be necessary for you or your mechanic to check the static air pressure above the engine during flight. The spec should be available from your airframe manufacturer.
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What does the Torque Link Stop Lug do?
The torque link stop lugs are more important than you would think. Overextension of the nose strut due to a worn out stop lug can lead to a cascade of problems. McFarlane A&P mechanics have seen struts over extend to the point where the metering pin comes out of the orifice. This results in loss of damping action and the pin hammering the orifice every landing and distorting and enlarging it. Over time, the excess nose strut travel and lack of damping can result in fatigue cracks in the torque link arms. McFarlane recommends thoroughly inspecting all nose strut components when replacing a severely worn stop lug.
The stop lug also acts as a centering device aligning the nose wheel and wheel pant straight with the airplane and slip stream after it has left the runway. Worn stop lugs can allow the nose wheel to lock in a turned position in flight that will require holding rudder for coordinated flight. Retractable gear aircraft depend on the stop lug to properly center the nose gear steering before it retracts into the wheel well.
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Is the proper nut and bolt torque important?
It is very important to maintain proper torque for the bolts that clamp the chrome bushing/spacer at the upper attachments to the steering collar and the lower attachment to the nose gear strut. It is commonly thought that the chrome bushing/spacer is kept in position by the bolt filling the center bore of the bushing/spacer. This is not correct as the inner bore of the chrome bushing/spacer and the bolt are a loose non-precision fit. The bushing/spacer is secured by the bolt end, clamping the spacer so that it is tight between the arms of the aluminum forgings. Any looseness of this end clamp will allow movement of the chrome bushing/spacer. This movement will erode the aluminum forgings and create more free motion of the torque link.
All shimming of the torque links must be done with proper torque on the bolts. Periodically and during nose gear inspections, check the torque on the upper and lower torque link bolts. If the chrome bushing/spacer is allowed to move, the resultant wear can require replacement of the expensive aluminum forgings. McFarlane is working on a repair for the worn aluminum forgings. Unlike our competitors, extra care is given to the machining of the McFarlane chrome bushing/spacers to give the largest possible bearing surface to the ends that bear against the aluminum forgings. Chamfers or bevels are kept very small.
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How can I make sure my oil temperature is accurate and identify the correct oil temperature range?
Placing a permanent reference mark at 180°F on the green band of your oil gauge is a good way to get accurate readings. To do this, simply place your sending unit and an accurate, referenced thermometer in a steel container filled with oil, and slowly heat it to 180°F with a hot plate. You may not be able to hold 180°F constant, so first mark your gauge with a pencil as the oil temperature passes 180°F. Then let the oil cool back to 180°F. Repeat the process to ensure accuracy.
And be extra careful with the hot oil. In a naturally aspirated aircraft engine, a cruise oil temperature significantly below 170°-180°F will not ensure that the moisture in the oil is boiled off, especially during short flights. As oil goes through the engine, the highest instantaneous temperature will be about 50°F higher than the oil sump temperature.
So, if you have an oil temperature of only 150°-160°F, the oil will not get above the 212°F necessary to boil off the water that can accumulate from condensation. The result is increased moisture and acid buildup in the crankcase, which will probably lead to rust and corrosion.
Knowing this is especially critical if your aircraft is not flown regularly and sits in a humid climate for weeks at a time. If your oil runs well below the 180°F mark, have your mechanic check your oil cooler system and vernatherm. Also, ask about a winterization kit.
Conversely, the concern with the typical turbocharged piston engine is excessive heat. In many of these engines, instantaneous oil temperature can increase 70°F or more at its hottest point versus sump temperature. These high temperatures can cause deposit buildup and increased wear due to improperly cooled components or low oil viscosity. (All oils, especially single grade oils, thin out as the temperature
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I installed a new fuel quantity transmitter and the system is still not working. What is wrong?
There are several other components in the fuel indicating system which could be the issue or are causing the indication problems:
- Ensure that your aircraft fuel indicating system utilized Stewart Warner style transmitters.
- Even if your aircraft originally came with that style, there were many Cessna Service Bulletins to replace them with the Rochester style. Our transmitters will not work with those components if they have been changed. This was a very common SB when Cessna switched over to Rochester.
- Transmitter Identification shows the difference in the Rochester style and the original Stewert Warner transmitter.
- McFarlane transmitters and Cessna Stewart Warner transmitters have an electrical resistance range of about 32 ohms when in the full position and 250 ohms in the empty position. This can be measured with an ohm meter connected between the wire terminal and the metal body. Note that the gold dichromate corrosion treatment on the zinc plating is a poor conductor. The metal body must be scratched a little to get a good electrical connection. The Rochester transmitter has a much different resistance pattern than the Stewart Warner or McFarlane transmitter.
- Consult your log books and check the part numbers of the fuel gauges and transmitters. Do not rely on Illustrated Parts Catalog or eligibility.
- With the age of most of the general aviation fleet, the possibility of corrosion in the wires or grounding is very likely. The gauge (indicator) may not be working correctly or properly calibrated.
- Since the transmitter gauge system works with very low voltage and very low milliamp electrical flow it is very sensitive to proper grounding and high resistance in electrical connections. Most problems are related to electrical connections.
- Excess resistance in the transmitter circuit can be detected by measuring the transmitter resistance with the transmitter being installed but without the wire connected at the terminal, and then measuring the resistance at the transmitter wire at the back of the gauge with the transmitter wire connected to the transmitter terminal and the transmitter wire disconnected from the fuel gauge and the other ohm meter connection to a ground at the back of the gauge. The resistance readings should be very close to the first resistance reading. In other words, you are measuring the transmitter resistance first without the airplane circuit and then comparing the reading with the airplane electrical circuit.
- If the preceding wiring check shows good, the problem is likely in the gauge. The fuel gauge has a brass grounding strap that grounds the internal electrical coils to the gauge case. With years of service this grounding strap can develop a thin layer of corrosion that restricts electrical flow. When this happens the gauge will show more fuel than what is in the tank which is not good! Cleaning this ground strap should fix the problem. Refer to the Cessna service manuals for detailed trouble shooting and maintenance information.
Caution! Never short the battery power to the transmitter wire! It will take only seconds before the stainless steel resistance wire in the Cessna transmitter will glow red hot in the fuel tank. The hot wire could explode the tank! Never have power on when trouble shooting the fuel gauging system.
Electricity in the Fuel Tank. Is it Safe?
Always check the fuel gauge system for proper calibration per the Cessna maintenance instructions.
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