General Safety & Scheduled Maintenance

General Maintenance Safety Principles

The following safety principles apply throughout all procedures in this manual. They must be observed regardless of which system is being serviced.

• 🥽 Personal Protective Equipment — Safety glasses, hearing protection, and appropriate gloves must be worn during inspection and servicing.
• 🔥 Fire Safety — Keep a fire extinguisher accessible when working near fuel systems. No open flame, smoking, or spark-producing tools near fuel handling or fuel-wetted components.
• ⚠️ Propeller / Engine Rotation Hazard — Treat any propeller as capable of firing the engine whenever the ignition system is connected, even with the engine "off." Confirm both magneto switches are OFF and verify the propeller is clear before any hand contact with the propeller or its arc.
• ⚡ Electrical Safety — Disconnect the aircraft battery (negative terminal first) before working on any electrical or accessory component, including the starter, alternator, and wiring harnesses.
• 🌡️ Hot Engine Components — Allow adequate cooling time before touching cylinders, exhaust components, or oil system parts after engine operation. Burns from exhaust components can be severe.
• 🔧 Foreign Object Damage (FOD) Prevention — Account for all tools, fasteners, rags, and hardware before closing any inspection panel or cowling. A tool or loose fastener left in the engine compartment is a serious airworthiness hazard.
• 📋 Maintenance Documentation — All maintenance performed must be properly logged in the aircraft and engine logbooks per applicable CAAP requirements.

What Is Scheduled Maintenance?

Scheduled maintenance is maintenance performed at predetermined intervals specified by the manufacturer's approved data, rather than in response to a specific problem. Intervals are expressed in flight hours and/or calendar time, whichever comes first.

Time Between Overhaul (TBO)

Per Continental Publication M-0, Table 6-1:

• O-200-A/B engines — serial number before 1006000 — Recommended TBO: 1,800 hours or 12 years, whichever comes first.
• O-200-A/B engines — serial number 1006000 and later — Recommended TBO: 2,000 hours or 12 years, whichever comes first.

Note on TBO for Part 91 operations: TBO is a manufacturer-recommended planning interval, not a hard regulatory limit for non-commercial Part 91 operations. However, noncompliance with manufacturer maintenance instructions may require earlier replacement of specific components and may affect airworthiness determination. NAAP's training fleet operations should confirm applicable regulatory requirements with CAAP.

Engine-mounted accessories and components require overhaul at the same hourly and calendar intervals as the engine unless a different interval is specifically stated for that component.

Airframe manufacturer's statement. D971-13 (Section 2, page 2-25) records that Continental recommends engine overhaul at 1,800 hours for the O-200-series engine, except as stipulated in Continental Aircraft Engine Service Bulletin M74-20 and supplements thereto. At the time of overhaul, engine accessories should be overhauled. This is consistent with the pre-serial-1006000 figure in Continental M-0 Table 6-1 above; where the two sources differ for a given serial number, the current Continental publication governs.

High-time inspection. A high-time inspection is a 100-hour inspection with the addition of an engine overhaul.

100-Hour and Annual Inspection Requirements

The 100-hour inspection covers all engine systems and must be performed by an appropriately licensed Aircraft Maintenance Engineer (AME) or equivalent. An annual inspection has the same scope as a 100-hour inspection but is required by regulation regardless of hours flown.

Per 14 CFR § 91.409: aircraft used for hire or flight instruction must receive a 100-hour inspection in addition to the annual inspection. This requirement applies to NAAP's training fleet.

Engine Inspection Checklist

Source: D971-13, Section 2, inspection charts (page 2-21) and Special Inspection Items (page 2-25).

Before using this chart, check for evidence of oil and fuel leaks, then clean the entire engine and compartment if needed. Items marked with a superscript number carry an additional special-inspection requirement, listed below the table.

Special Inspection Items

• 1 — Engine oil. First 25 hours: refill with straight mineral oil (non-detergent) and use until a total of 50 hours has accumulated or oil consumption has stabilised, then change to ashless dispersant oil. Change oil each 50 hours if the engine is not equipped with an external oil filter; if equipped with an external oil filter, change the filter element each 50 hours and the oil each 100 hours; or every 6 months.
• 2 — Induction air filter. Clean per paragraph 2-22. Replace as required.
• 3 — Hoses. Replace hoses at engine overhaul or after 5 years, whichever comes first.
• 4 — Intake and exhaust. General inspection every 50 hours. Refer to Section 11 for the 100-hour inspection.
• 5 — Vacuum relief valve filter. Each 1,000 hours, or to coincide with engine overhaul.
• 6 — Engine controls. Each 50 hours for general condition and freedom of movement. These controls are not repairable — replace as required at each engine overhaul.

Inspection Guidelines

Source: D971-13, Section 2, paragraph IV (Inspection Guide Lines).

These define what to look for on each class of component during any inspection.

• Movable parts — lubrication, servicing, security of attachment, binding, excessive wear, safetying, proper operation, proper adjustment, correct travel, cracked fittings, security of hinges, defective bearings, cleanliness, corrosion, deformation, sealing and tension.
• Fluid lines and hoses — leaks, cracks, dents, kinks, chafing, proper radius, security, corrosion, deterioration, obstruction and foreign matter.
• Metal parts — security of attachment, cracks, metal distortion, broken spotwelds, corrosion, condition of paint and any other apparent damage.
• Wiring — security, chafing, burning, defective insulation, loose or broken terminals, heat deterioration and corroded terminals.
• Bolts in critical areas — correct torque per the torque chart, when installed or when visual inspection indicates the need for a torque check.
• Filters, screens and fluids — cleanliness, contamination and/or replacement at specified intervals.

Airworthiness Directives (ADs)

Applicability of specific Airworthiness Directives depends on the individual engine serial number. Verify the current AD status against the engine's maintenance records before performing maintenance. Two ADs are known to apply to certain O-200 series engines:

• AD 93-10-02 — Teledyne Continental Motors reciprocating engines: cylinder assembly inspection.
• AD 94-4837 — Teledyne Continental Motors Models C75, C85, C90, C125, C145, O-200, O-300, and GO-300 series: rocker shaft boss inspection.