PROP GUARD will stop water erosion of the propeller and has been used on seaplane applications. However, it has very limited life on high speed propellers that are subject to a lot of water spray. Water spray will reduce the life of PROP GUARD as the constant impact of the water droplets will eventually fatigue the material causing it to become more brittle with progressively less ability to absorb energy. This constant water hammering will eventually cause it to shred, starting at the prop tip area. This is a harmless situation that causes no concern in flight, but it will require repairing the PROP GUARD installation. Some seaplane operators use PROP GUARD knowing that they will have to frequently replace PROP GUARD at the prop tip area. By sacrificing itself, the PROP GUARD has stopped considerable prop erosion. PROP GUARD will hold up relatively well on lower horsepower applications where the propeller has good water clearance.

Yes. The fuel screen is removed by removing the standpipe. The rubber tipped plunger must be unseated before the standpipe is loosened. Failure to lift the plunger off of its standpipe seat can damage the plunger. Pull the strainer drain knob as if you were draining the fuel bowl. Block or clamp the knob in this position. Insert a smooth round tool such as a screw driver or punch in the standpipe cross-hole and un-screw the standpipe.

Here are some eligibility search tips:

• If you do not know your serial number, you can just select your aircraft make and model.
• The model you select must be specific: a 172 is not the same as a 172B.
• Serial numbers must be complete: for example, 15073660 cannot be entered as 73660.
• Hyphens in serial numbers are optional: for example, 28-7325001 and 287325001 are considered equivalent.
• For web browsers with JavaScript enabled, you do not need to click the Submit button when you select a make or model. After typing a serial number, you do need to click the submit button.
• Due to the limitations of our product database, some parts that are eligible for your aircraft may not appear on the returned list of products when your aircraft make, model, or serial number is selected. If you can't find what your looking for, please call or email us.
• Due to the possibility of error in eligibility data and the possibility of non-standard aircraft configurations, McFarlane Aviation, Inc. cannot be responsible for application of our products. The user of the products must verify correct eligibility and function of our products.

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

We make the following cleaning and sanitizing recommendations to be completed between flights:

Recommended Cleaning Process

1. Put on clean disposable gloves prior to cleaning and disinfection.

2. Pull controls back to the fully retracted position to expose the full length of the control shafts.

3. Apply isopropyl alcohol to a clean microfiber towel. Do not spray any solution directly on the controls or any other surfaces or components in the aircraft.

    !!! WARNING: DO NOT USE BLEACH WIPES ON ANY MCFARLANE CONTROL !!!

4. Gently and thoroughly wipe down every control knob surface and control shaft.

5. Let cleaning solution dry on these surfaces (contact time).

6. Use a clean and dry microfiber cloth to wipe away any solution residue left on knob and control shaft surface.

7. Remove all gloves, towels, and cleaning supplies from the work area in the aircraft.

Please contact McFarlane Sales directly at 866-920-2741 or 785-594-2741 or sales@mcfarlaneaviation.com if you have any additional questions regarding the disinfection of our controls.

The new fully automatic chargers on the market today need to be hooked up to a battery before they will output any voltage. This is primarily a safety feature that prevents spark when hooked up, and protects the charger against reverse polarity hookup. Some chargers need to see as much as 9V volts before they recognize that they are attached to a battery. Once the charger is hooked up, it should output 13.9-14.6 volts. If your charger does not do this, you may want to contact the manufacturer for further troubleshooting tips.

The Cessna steering system is an engineering masterpiece that is simple in function while allowing good directional control throughout the transition from flight to ground or ground to flight, even in crosswind conditions. A key part of this system is the steering rods. The steering rods are a spring loaded device that applies spring pressure to pull on one side of the nose gear when it is activated and yet have a specified amount of free play in the opposite direction until a solid push is required for positive steering.

The following are some common symptoms of worn out or failed steering rods:

1. Weak steering (You can push on the rudder but not much happens and you have to use a lot of brake to steer. Often the weakness is one direction only.) The early Cessna steering rod springs were designed such that if the rudder pedal was pushed hard in one direction while the nose gear was pointed all the way the other direction and had some resistance to moving such as soft ground or snow, the spring could be compressed to an extent that it would be permanently shortened leaving it weak. McFarlane has redesigned the spring so this cannot happen.
2. More or less than 1.2 inches of free play movement or inconsistent free play of the steering rod shaft is present. The spring is retained by a washer that was stop swaged into the steering rod housing. During an overload, such as extra hard pedal force applied with the nose wheel pointed all the way in the opposite direction and restricted or undetected damage from a previous hard landing, the spring retaining washer can be deformed and forced past the swaged stop. This will result in inconsistent free play and erratic function of the steering rod shaft as the washer passes past its designed swaged stop in both directions. The rudder rigging in flight might also be inconsistent. This is a dangerous situation that results in inconsistent steering and the steering rod must be replaced. McFarlane has redesigned the washer and shaft machining to prevent the washer stop failure.
3. Rust and corrosion can make the steering rods unreliable. The steering rods get water and contaminates from the runway that the nose tire throws at them. The fit of the shaft into the bushing that is swaged into the housing is not a precision fit. This can allow internal contamination, moisture, and salt that will rust the springs and steel housing interior, leaving the components weak and subject to failure. Red rust streaking on the shaft exit area or bubbling of the exterior paint indicate corrosion failure. The McFarlane steering rods are made from 304 stainless steel and have a special corrosion preventative and lubricating coating on the springs to fight against corrosion and wear.
4. Wear of the shaft and bushing is caused by steering movement and aerodynamic pulse vibrations created by the rotating propeller. This wear can be detected as looseness of the shaft in the end bushing. Some wear is acceptable.

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.

It is critical the owner or maintenance shop obtain a PN off the brake master cylinder assembly, not from the IPC manual. 

Use a straight edge as seen in Figure 1-3 to see if it's bent. 

All battery types lose power and capacity as they age. The rate of when this happens depends on the maintenance of the battery and how it has been used (or abused).

• If you notice your battery just doesn’t have the same “umph” as it used to, it might be time to replace it.  In the cold this issue is more prominent.
• If you notice the battery is “swollen.” As the battery ages, gases can build up inside the battery and make the battery look bulging or swollen. The gases are not dangerous or have any safety issue, but the pressure can puff the case.
• If the battery is left in a discharged state and then very quickly charged, the cells can puff causing the case to look bulging.
• The battery will not hold a voltage above 13.28V for the 12V vehicle applications or 26.56V for 24V vehicle applications.
• The fault light is solid or flashing on the battery models that have the LED alert and is consistently on for days.

The most common indication of external fuel valve leaks is the smell of avgas in the cabin. Most valves are located under the cabin floor. Fuel stain on the valve and drain plug or drain valve or on the belly of the aircraft can also indicate external leakage. External leaks are generally around the actuation valve stem. Internal leaks are detected when the fuel is turned off and fuel continues to drip during fuel system maintenance. Inner port leakage will allow fuel from one tank to leak into another fuel tank. This type leak is difficult to detect. Fuel transfer from one tank to another with the fuel valve selected to one tank only will indicate inner-port leakage. An extended period of time is needed to detect fuel transfer from one tank to another. Generally if internal leakage is detected when servicing the fuel system, it is likely there is also inner-port leakage. 

The screw kit depends on if the holes in the floor of your airplane have been carefully removed and are close to new size or if they have been enlarged by unskilled rivet removal or the rails have been changed before. It will make a difference if the previous rails installed were Cessna rails with predrilled holes in the rail. (They do not normally line up well and the floor has been mis-drilled some to force them to align). If the holes are good, use the SR6-SCREW-KT kit. If the holes are enlarged some, use the SR8-SCREW-KT kit.

To learn how to measure controls for custom manufacture see;

How to Measure Your Engine Control (Quadrant)

How to Measure Your Vernier Engine Control (Knob)

The McFarlane primer is available as a complete fuel primer assembly and knob assembly only, and replacement seals for the knob assembly are available. In many cases, where the old primer bore is still good, the McFarlane knob assembly can be used for a FAA-PMA approved quick fix for your existing primer.

The laser marking does not harm the hard durable anodize coating on the aluminum knob. The CO2 laser process only bleaches the color from the anodizing leaving a silver white color that contrasts with the surrounding dyed anodize. The durability of the laser marked area is not affected by the laser. Our tests have shown that the laser process actually improves the corrosion resistance of the anodize layer. The CO2 laser engraves aluminum knobs by vaporizing the surface leaving a deep durable groove. This groove is then filled with a special paint for contrast. The result is a durable long lasting mark.

Most of the time, it means you need to charge the battery as it is at a low charge level but it could mean several things. First thing you need to do it put a voltmeter on the battery, if the voltage is less than 13.28V, the LED light will flash to let you know to charge the battery. If the voltage is above 13.28V and flashing, then you could have a weak cell /a cell out of balance/or defective cell and you need to contact EarthX for a warranty coverage if it is less than 2 years old. The LED will also flash if the voltage is too high, above 14.6V. If the light is solid and remains on for more than 10 minutes, then it is an indication of a BMS electronics problem and contact EarthX.

The ETX-Series of batteries have over discharge protection and is designed to prevent a continuous active drain on the battery to the point of damaging the battery, such as leaving your key in the on position, master switch on your aircraft, or parasitic draw as examples.  If your battery is reading 0V, or near 0V, then this protection might be activated.

To determine the actual voltage of the battery, remove the negative battery cable and measure the voltage at the terminals with a voltmeter.  If less than 8V, it will not accept a charge.  Once a lithium battery is approximately 8V, it can be permanently damaged and the EarthX BMS is designed to not allow the recharging of the battery as this is no longer safe to do and can be dangerous and cause cell rupture.  Never force a charge into the battery. This is not a battery defect, nor a failed battery, but instead the protection working as it is designed.

The rate of discharge depends on how many amp hours the battery has (less Ah = faster discharge) and the ambient temperature (warmer = faster discharge).  When the EarthX battery is about 95% drained, the BMS over discharge protection will disconnect the battery from the active drain so that you do not continue to discharge the battery to the point of damaging it. You know this has happened when you put a voltmeter on the battery installed in the vehicle and it reads close to 0V. We allow this much discharge of the battery to provide you the most energy possible if the drain is intentional, ie: your alternator fails in flight, and you are powering your electronics with the battery. The battery will continue to drain, at a much slower rate, with time as this is impossible to stop batteries from self-discharging.  Even “brand new” batteries left in a box will drain and if not recharged and maintained, will be permanently damaged.

It is very important to recharge the battery immediately if it has been drained.  The longer the battery remains discharged will shorten the overall life span and increases the chance of permanent damage.

Depending on the amp hour of the battery and the environmental temperature will dictate how much time can pass before it is permanently damaged.  Example, the ETX12A is a 4Ah battery and should be recharged within a week whereas the ETX900 is a 15.6Ah battery and should be recharged within a month of finding it in this state.

You don't need to, but it's not a problem if someone doesn't know the bushings have been fitted and decides to put lubrication into the hinges. The bushings will function properly in oil or grease, but it is not necessary.