An aircraft and engine company from Australia and their aim is to develop and sell reasonably priced aircraft and engines. We do not know of many companies building both aircraft and engines, but Jabiru Pty is one of them. Development started when the need came to power their in house designed aircraft when their engine supplier ceased production.
They started with a 60 bhp 1600cc engine to power their aircraft and after many moons this resulted in the 80 bhp four cylinder Jabiru 2200, followed later by the 120 bhp six cylinder Jabiru 3300. At one time they were also working on an eight cylinder Jabiru 5100.
They also manufacture a successful line of experimental and certified aircraft ranging from two to four seaters, all developed around and powered by their own engines. We will concentrate on the powerplants here.
This part two is going to take a look at the internal engine part as valve gear, oil pump and cooling of the engine.
Lubrication is accomplished by an oil pump driven by the camshaft, as seen in so many aero engines. Oil change interval should be around 100 hours, but expect this to be lower when using leaded fuels (AVgas).
The valve gear includes push rods from the camshaft from the camshaft followers to valve rockers which are CNC machined from steel plate, induction hardened and polished on contact surfaces and mounted on a shaft through an aluminum bronze bush. GEN3 introduced hydraulic roller valve lifters and cam, those are now used in all new engines.
Valve guides are manufactured from aluminum/bronze, as is found in larger aero engines and high performance race engines. Replaceable valve seats are of nickel steel and are shrunk into the aluminum cylinder heads. The valve gear is lubricated from the oil gallery.
An internal gear pump, directly mounted on the camshaft and incorporating a small automotive spin-on filter, provides engine lubrication. An oil cooler adapter is provided. Most installations will require an oil cooler to meet oil temperature limits.
The recommended oil to be used in the engine is any standard aviation type multigrade oil.
The standard engines are supplied with two RAMAIR cooling ducts, which have been developed by Jabiru to facilitate the cooling and direct air from the propeller to the critical areas of the engine, particularly the cylinder heads and barrels.
The fact that these baffles and plenum chamber are not required also ensures a "cleaner" and much easier engine installation, which in turn facilitates easy maintenance and inspection of the engine and components. RAMAIR ducts are available for tractor or pusher configurations. Special ducts are available for certain installations.
The fuel induction system comprises one BING pressure compensating carburetor. Following carburation, the fuel/air mixture is transported to a small plenum chamber in the sump casting, in which the mixture is warmed prior to entering short induction tubes attached to the cylinder heads.
An effective stainless steel exhaust and muffler system is also fitted as standard equipment.
Geronimo Experimental Aircraft is developing a supercharger installation for the Jabiru 3300 engine. The installation weighs 22 lbs, but if you replace your lead-acid battery with one from EarthX you can offset some of that weight. Boost is regulated by a small controller and kept to around 34 inHG up to 10000 ft. More information on the website of https://geronimoeabc.com/kits/.
Text partially from Jabiru.Written by EAI.