What a fantastic day with a great bunch of people ….
Flew out from misty foggy Jersey yesterday to even mistier and foggier Gatwick and then long drive up to Holbeach to stay in a small pup overnight ahead of today’s starter course for those who want to know a bit more about the Jabiru 2200 engine.
Started with lubrication … a very good place to start …
Next … electrics … not everyone’s favourite …
Next … mechanical bits … valves and tappers and compressions ….
My engine .. serial 22A-2111 is a hydraulic lifter tappet type… so does not require the above adjustments
8.19 Hydraulic Valve Lifter Maintenance
The Hydraulic Valve Lifters used in the engine automatically adjust for any valve movement, so periodic adjustment of the valve clearances is not required, however the valve lifters are a serviceable item and some monitoring is required to ensure they are working properly.
EITHER – Remove each rocker cover and check that each lifter has not collapsed. This is done by turning the crankshaft so that the valve is fully in the closed position, then feeling the rocker by hand. There should be no free rotation of the rocker. Press down on the pushrod end of the rocker – the lifter should feel hard, with minimal movement possible under thumb pressure. Note that the correct method for finding this point is to turn the crank until the valve is fully open, then turning the crankshaft through one complete revolution to rotate the cam lobe away from the lifter.
OR – after the service, idle the engine, listen for loud tapping noises and feel for rough running. This must be carried out with the cowls removed. Note that due to the need to have a person at the controls of the aircraft, this is a two-person job.
We also got shown where d bolts are for tightening down to 24flbs but set to 23 to be on the safe side with us … also noted where the small grub screw is that reveals the 5th head bolt for tightening … this could be where I have a small smear .. to be checked
Don’t overtorque your head nuts Flywheel bolts need replacing at 100 hours
really neat heater box on an engine in for service
Other useful bits to write up from my little notebook.
- Oil breather pipe should rise initially before dropping away to catch bottle …
- Oil excess overflow should not have a drain pipe that could end up pressurising the crankcase
- Carb balance air pipe should come from filtered side of carb and into filtered side of air filter …should intrude by 20mm for good fit
- Check the carb is earthed to engine
- Flywheel bolts now have special new nordloc washers and new bolts ..old bolts need changing at 100 hours .. new ones won’t … the old ones could well be difficult to get out…remove spider … heat can be used to break the loctite .. but .. make sure you protect the magnets .. once heated .. let it cool right down first before trying to break the seal
- When setting tappets ALWAYS do it cold .. so good plan .. drain oil hot from a run .. leave overnight to fully drain … then take a plug out to reduce turn pressure on prop and get piston to TDC then adjust as above
- Good idea to make a mark on stator for where TDC is per cylinder
- Check the small bung grub screws inside the tapper cover head .. these can come loose and cause oil to spill down thetappet pushrod guide tubes .. think I may well have this on mine !
- Push rod tubes are rubber o ringed at bottom and circlipped at top
- When replacing the inlet manifold rubbers .. prob best to cut the old ones off .. remove jubilee clips … then a bit of grease and turn the outer manifold pipe through 45’ .. it’s only on a rubber o ring to turning it makes new pipe slip on really easy
- Note .. when checking torque on ALL cylinder head bolts .. start at 23 ft lbs and remove the bung acts which allows long drive access to 5th head bolt for torquing
- All electrical parts should be Bosch .. distributor cap, rotor arms etc
- Remember the ‘hidden’ filter in the pump
- Oil pump return valve spring and fitting … push check … to make sure it’s free moving
- Jabiru carb needle jet options … AUS vs U.K. … N2 for U.K. with fully tapered jet needle vs single bar straight sided needle for AUS market and weather conditions