Rotax Aircraft Engine Maintenance Plan for Rotax 377, Rotax 447, Rotax 503, Rotax 532, Rotax 582, and Rotax 618 aircraft engines.
The maintenance plans included here are for information only, always carry out work, checks and inspections in accordance with the Operators Manual provided with your engine, and any subsequent service bulletins issued.

Daily Inspection (2-stroke engines)

  

Pre-flight Inspection (2-stroke engines)
1 Check ignition switched off. >>> 1 Check ignition switched off.
2 Drain water from fuel tank sump and/or water trap (if fitted). >>> 2 Check fuel content.
3 Check carburetter rubber socket or flange for cracks and secure attachment.   3  
4 Check carburetter float chamber for water and dirt.   4  
5 Check security and condition of intake silencer and air filter.   5  
6 Check security of radiator mounting. Check radiators for damage and leaks. >>> 6 Visual check of coolant leaks.
7 Check coolant overflow bottle and radiator header tank for level and security of cap.   7  
8 Check coolant hoses for security, leaks and chafing.   8  
9 Check engine for coolant leaks (cylinder head, cylinder base and water pump).   9  
10 Check oil content for rotary valve gear lubrication and security of oil cap.   10  
11 Check oil hoses for security, leaks and chafing (rotary valve gear lubrication system and oil injection system). >>> 11 Check oil tank content (oil injection engines).
12 Check ignition coils / electronic boxes for secure mounting. Check ignition leads and all electrical wiring for secure connections and chafing. >>> 12 Check spark plug caps for security.
13 Check electric starter for secure mounting, check cover for cracks.   13  
14 Check engine to airframe mounting for security and cracks.   14  
15 Check fuel pump mounting for security. Check all fuel hose connections, filters, primer bulbs and taps for security, leakage, chafing and kinks.   15  
16 Check fuel pump impulse hose for secure connections, chafing & kinks.   16  
17 Check wire locking of gearbox drain & level plugs. >>> 17 Visual check of engine and gearbox for oil leaks.
18 Check rubber coupling for damage and ageing (C & E type gearbox only). >>> 18 Visual check of engine and gearbox for loose or missing nuts, bolts and screws.
19 Rotate engine by hand and listen for unusual noises (double check ignition off first!).   19  
20 Check propeller shaft bearing for play by rocking propeller. >>> 20 Check propeller for splits and chips. If any damage, repair and/or rebalance before use.
21     21 Check security of propeller mounting.
22 Check throttle, choke and oil pump lever cables for damage. >>> 22 Check throttle, oil injection pump and choke actuation for free and full movement.
23     23 Check cooling fan turns when engine is rotated (air cooled engines).
24     24 Check exhaust for cracks, security of mounting, springs and hooks for breakage and wear, check wire locking of springs.
25     25 Start engine after ensuring area clear of bystanders.
26     26 Single ignition engines – check operation of ignition switch (flick ignition off and on again at idling).
27     27 Dual ignition engines – check operation of both ignition circuits.
28     28 Check operation of all engine instrumetns during warm up.
29     29 If possible visually check engine and exhaust for excessive vibration during warm up (indicates propeller out of balance).
30     30 Check engine reaches full power rpm during take off roll.
 
2-stroke Maintenance: The following maintenance is planned and necessary for Rotax 447 UL SCDI, 503 UL DCDI, 582 UL DCDI and 582 UL DCDI mod 99 (adapted from Maintenance Manual initial issue May 01/99).

Checks and Work

Operating Hours
2 10 12˝ 25 50 75 100 125 150 175 200 225 250 275 300
1 Ground run       x                      
2 Level check of liquids x                            
3 Retorque cylinder head nuts (1) x                            
4 Retorque exhaust manifold screws (1) x x                          
5 Check rewind starter rope (10)     x                        
6 Check electric starter gear         x   x   x   x   x    
7 Inspect spark plugs (10)     x                        
8 Replace spark plugs       x x x x x x x x x x x  
9 Check ignition system       x                      
10 Check and clean inside spark plug caps (10)     x                        
11 Checking of V belt tension   x   x x x x x x x x x x x  
12 Lubricate ball joints       x x x x x x x x x x x  
13 Replace exhaust muffler springs           x     x     x      
14 Lubricate control cables (3)       x x x x x x x x x x x  
15 Check propeller balance & tracking (2,3)       x x x x x x x x x x x  
16 Inpect propeller mounting bolts (3)                              
17 Clean and oil air filter       x x x x x x x x x x x  
18 Check fuel filter       x x x   x x x   x x x  
19 Replace fuel filter             x                
20 Check carburetter(s) & readjust (idle speed, cable tension..) x     x   x   x   x   x   x  
21 Clean carburetter(s) & check for wear         x   x   x   x   x    
22 Replace jet needle & needle jet                 x            
23 Check fuel pump (measure fuel pressure)           x     x     x      
24 Check gearbox oil level       x x x   x x x   x x x  
25 Replace gearbox oil   x         x       x        
26 Check & adjust gearbox, preload of springs (type B gearbox)             x       x        
27 Replace rotary valve lubrication oil             x                
28 Inspect cylinder head & piston crown (4)         x   x   x   x   x    
29 Inspect piston rings for free movement (5)         x   x   x   x   x    
30 Check piston diameter (7)         X   X   x   X   x    
31 Piston ring: check gap (7,11)         X   X   x   X   x    
32 Piston ring: check axial clearance (rectang. ring) (8,12)         X   X   x   X   x    
33 Check cylinder diameter (7,11)         X   X   x   X   x    
34 Cylinder, check for roundness (7,11)         X   X   x   X   x    
35 Replace cylinder head, cylinder base & exhaust gasket (8)         X   X   x   X   x    
36 Inspect piston pin & bearing                 x            
37 Inspect crankshaft & replace outer seals if necessary                 x            
38 General overhaul of engine (9)                             x
Bold X – see note 6.
Notes:  
1) And after every replacement of gaskets 7) Wear limit see service information 5UL91
2) Also after any damage 8) If cylinder has been dismantled
3) According to instructions of manufacturer 9) To be carried out every five years or every 300 hours whichever comes first. Contact authorised distributor or Service Centre.
4) If carbon layer is more than 0.5mm thick, decarbonise
5) If piston ring sticks clean and replace if necessary 10) To be examined after every 12.5 hours of operation.
6) If used in very dusty atmosphere 11) Necessary only if piston rings are not freely moving.

Rotax 4-stroke Engine Maintenance Schedule
(adapted from 912 Maintenance Manual Rev 1, Jan 01/2002)

Checks and Work

Every…Hours
25 50 100 200 600
1 Engine cleaning x x x x x
2 General inspection of the engine for damage and abnormalities, including obstructions, cracks, wear and condition of cooling air ducts, baffling and cylinder cooling. Take notes of changes caused by temperature. x x x x x
3 Inspection of temperature & oil pressure sensors. Inspect for tight fit & condition. x x x x x
4 Inspection of all coolant hoses for damage, including leakage, hardening from heat, porosity, loose connections and secure attachments. Verify routing for kinks and restrictions like restricted elbows. x x x x x
5 Inspection of leakage bore at the base of the water pump for signs of leakage. x x x x x
6 Inspection of expansion tank for damage and abnormalities, including damage from heat, deformation. cracks. Verify coolant level, replenish as necessary. Inspect radiator cap. Inspect rubber plate on expansion tank base for secure fit. x x x x x
7 Inspect overflow bottle for damage and abnormalities, including: verify coolant level, replenish as necessary. Inspect line from expansion tank to overflow bottle for damage, leakage and clear passage. Inspect venting bore in cap of overflow bottle for clear passage. x x x x x
8 Inspect all oil lines for damage, leakage, hardening from heat, porosity, security of connections and attachments. Verify routing for kinks and restrictions including restricted elbows. x x x x x
9 Inspect all fuel lines for damage, leakage, hardening from heat, porosity, secure connections and attachments. Verify routing for kinks and restrictions including restricted elbows. x x x x x
10 Verify the complete electrical wiring system including tight fit of connectors, damage & wear. x x x x x
11 Inspect engine mounts and fasteners for secure fit, including damage from heat, deformation & cracks. x x x x x
12 Inspect attachement screws and nuts of all external parts for security & fit. Inspect safety wiring, replace as necessary. x x x x x
13 Verification of the friction torque. Actual friction torque _________Nm (in.lbs). x x x x x
14 Gearbox of engine configuration 3 (with slipper clutch) and using leaded fuel in excess of 30% of operation. Inspect overloaded clutch.         x
15 Before inspect oil level, turn propeller over several times in normal rotation to ensure that oil in the crankcase has been returned to the oil tank. This process is finished when air is returning back to the oil tank and can be noticed by a murmur from the open oil tank. Inspect oil level. x x x x x
16 Inspection of the magnetic plug.       x x
17 Remove oil drain screw from oil tank. Drain old oil and dispose as per environmental regulations. x X x x x
18 Remove oil filter from engine and install new oil filter. Lubricate mating sealing ring of new oil filter with engine oil. Screw on new filter by hand. After the engine test run, tighten again by hand. x X x x x
19 Cut oil filter housing without producing any metal chips and inspect filter mat. Findings_______________________________________________________ x X x x x
20 Replace gasket ring of drain screw on oil tank. x X x x x
21 Refill oil tank with approx. 3 litres of oil. For oil quality rever to OM and SI-18-1997. x X x x x
22 Flushing of the cooling system.       x x
23 Inspection of the air filter. x x x x x
24 Inspect the carburetter sockets for damage and abnormalities, including obstructions, cracks, wear and condition. Take note of temperature influence.       x x
25 Verification of the idle speed. x x x x x
26 Verification of the float chamber venting. Inspect venting lines for condition and damage including for condition, secure attachment, clear passage routing without kinks and restrictions. x x x x x
27 Inspect free movement of the carburetter activation (throttle lever & starting carb). Inspect that the Bowden cable allows the full travel of the throttle lever. x x x x x
28 Inspect the carburetters: remove, disassemble, clean, inspect all components including jetting, leakage test of float needle valve, reassemble and reinstall the carburettors.       x x
29 Inspect carburetter synchronosation. Mechanical and pneumatic synchronisation. x x x x x
30 On engines with an external alternator, inspect the attachment and the V-belt tension for damage and abnormalities, including obstructions, cracks, wear and condition. x x x x x
31 Remove all spark plugs, verify heat range, clean the spark plugs. Inspect electrode gap & adjust as necessary. Replace as required.     X x x
32 Renewal of spark plugs. Clean sparking plug thread and the sparking seat. Apply heat conduction compound on spark plug thread.     X x x
33 Verify security of spark plug connectors. Minimum pull-off force is 30 N (7lb). x     x x
34 Inspect compression by differential pressure method. Test pressure________hPa (psi). pressure drop cyl 1_______, cyl 2_______cyl 3_______cyl 4_______.       x x
35 Start the engine and run to operating temperature. Inspect of ignition circuits at 4000 rpm engine speed. Speed drop without ignition circuit: A__________rpm, B_________rpm. Inspect carburetter preheating. Fully activate preheating and record rpm drop____________.

Preheating off, bring engine to idle speed and record idle speed___________rpm. After engine test run, re-tighten the oil filter by hand.

 x x x x x
36 All Service Instructions and Bulletins are complied with. x x x x x
Bold X – for engine operation with AVGAS and/or severe coperating condition.

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