Jabiru GEN4 engine a closer look

[@foesfly3047]

Paul, I’m happy to see you looking this closely at the Gen-4. I’m about to finish installation of a 3300 that replaced a 2200 Gen-2. If you develop any improvements for the new G4, I’ll be interested. Disappointed to hear my Rotec External Alternator won’t fit the Gen-4. I have kept the one I ran on the 2200 Gen-2. Thank you for producing this video. Huge respect for your work ♠️

[@jpdurr]

still needs FADEC EFI if only as an option. It's 2023 for Christs Sake!

[@GlideYNRG]

Carburettor looks similar to the stock Mikuni 40mm carburettor off my old 93 Harley. With the right mods they're a good carburettor. They can go up to a 50mm CV type carb. Thankyou for the interesting run down.

[@Jeff034]

Brilliant engine. Needed to block half the air off the oil cooler on mine in less than 25 deg c ambient to get the oil temp off the stops. Pulls like a …

[@jaybee6143]

Talking to Rod before I purchased my Gen 4, he did say that the factory had rebuilt “several” earlier Gen engines with Gen 4 parts, but it was not economically viable for the factory to do it. That makes sense to me, as they were flat out producing engines, with long waiting lists, so rebuilds were not a priority for them at tha time. The new owners of Jabiru may change Rod’s policy of no fuel injection and solid state ignition, I suppose that time will tell..

[@raydreamer7566]

With these new improvements on this motor I wonder if they will bring back the 8 cylinder motor ? ? ?

[@rixward5475]

Thanks for the video, good to see new evolutions.What are the bore & stroke, also the max revs? surprised these aren't EFI

[@chippyjohn1]

Thanks for the walk around mate. They are simple looking, but I still prefer liquid cooled EFI any day. I would like to build a mid engined single or dual prop liquid cooled using the fuselage, especially leading edge as the heat exchange. People seem to be afraid to try something different in aerospace.

[@jayknight850]

Nice looking engine, FADEC would be a worthy addition.

[@bryanst.martin7134]

Thank you Mate! I wondered about them. As a mech for a half Century and working on everything from PW R2800 to DDA T56A-14, to Detroits, Cummins, Harleys, and many more, I am not impressed. I have an EJ22 planned for a small seaplane and I will stick with OEM cooling system and light boost with a PSR of sorts. Especially when I can port heat from the radiator to the cabin. Built VW engines too, didn't like the PR tubes. Another failure point. And does it use an evacuated Crankcase? Someone went to a lot of trouble to make that, but I stand opposed. But to each his own.

[@garymitchell6897]

Do the cylinder through bolts have a nut one one end only or is it a stud threaded at each end?. If it’s a stud type you would have to guess the amount the first nut is screwed on and then hope the other nut doesn’t turn stud and upset the other end.

[@drlescrawford897]

The question, have the gen 4 modifications resolved the overheating issues (of previous versions)?

[@chrismitchell4622]

Would be interesting if it could use future SAF?

[@louisvanrijn3964]

This type of carburettor is not that bad. The needle which steers the mixture over the load cycle can be tuned. It that case, full power, of 90% of power can have a rich mixture, preventing the engine from overheating. Rotax does the same with its FADEC, it runs at lamda is 0,86 above 85 % power.

[@FairladyS130]

The only questions I have is why are the inlet and exhaust pipes so close together and using a 'rubber' seal for the head inlet pipe is potentially problematical. Relatively high temp 'rubbers' are available but still.

[@genebaket]

The Gen 4 has been out 4 years, why the review now?

[@robinj.9329]

I don't know anything about these engines. Q. What is the displacement and the Horse power? And what is RPM at "Red Line" and extended cruise?

[@bigmuz_pilot]

Other than the piston availability issues do you think they have sorted every one of their weak points in the gen 3?

[@jcmate1692]

Keeping these engines cool has been the issue right from the start, bite the bullet talk to some smart casting companies and experts in the latest CNC machining techniques and water cool these engines along with EFI. The water cooled heads they done are a joke a bandade solution with more things to go wrong.

[@Paulman50]

Cool motor. Did you build the 3 cylinder rotary that's being tested in the 2023 Myers Max dune buggy, that's real sweet.

[@regdor8187]

Cylinder clamping with three long studs and 0ne short one will distort the cylinder with heat and time giving out of round cylinder bores.....IMHO....

[@karlkleimenhagen9918]

I don't know why he that short one in there, but as seen in other views, all the studs are the same (long) length.

[@jayknight850]

They are through bolts, not really studs by definition.

[@user-gk7dv5go1r]

Там редуктора понижающего для винта нет?

[@tonywright8342]

Jabiru don’t have reduction gear, they are direct drive.

[@henryware9440]

So, with your very good ignition system, why couldn't a guy pull one spark plug and replace it with an injector (as in fuel injection)? If you used exclusively Mogas and with your ignition system, why does a guy need two spark plugs?

[@semiprofessional8470]

Redundancy and cost I suppose. With this setup you could lose a lot before it started dropping cylinders. You'd have 1 injector and 1 plug. If either fails you loose that cylinder

[@ryoungatlmidotnet]

A number of aviation authorities require dual ignition.

[@eugeneoreilly9356]

Thought this would be a good engine until he mentioned Nikasil coated cylinders.Seems Jabiru never learned anything from BMW,s short lived disaster with this production method for their early 90,s engines.Scrapyard material by 60,000 miles.

[@tinolino58]

You need an update

[@tonylam9548]

When a company is so resistance to changes that another had to step in and make water cooled cylinder heads for upgrade, this is not a good sign. Some comments mentioned FADEC, it is a joke right , for this engine still use a carburator, which is only found on lawn mowers and chain saws nowadays. Even Rotax , never quick to introduce new products, is all injected. I also saw 2 distributors, does it use breaker points inside?? Is there a manual spark advance?? Like in the Ford Model A?

[@jcmate1692]

In this day and age with casting techniques and the advances in CNC machining why are these cylinders and heads not water cooled. Water cooling may add a few kg but on hot day of around 36 to 40 degree Celsius in the 4 cylinder motors your not going to be struggling to get the aircraft off the ground with 2 big guys in it with a combined weight of 200 to 220 kg. I may be wrong but to me these new water cooled heads look like some back yarders modification, more fittings more hoses, more hose clamps, just more places for things to fail.

[@fb2800]

@jcmate1692 I'm not sure what you mean. Firstly our LCH conversion for Jabiru engines is not compatible with this gen 4 engine as its has different cylinder assemblies. LCH has proven (15 years in production) to be an excellent solution in addressing the cooling issues on the earlier gen 1-3 engines. Neat and tidy too. We use 356A casting alloy heat treated to T6 temper.