Old Koreelah

That Taiwanese engine seems to have an alternator under the flywheel (thus concentrating all the innertia storage in one area) avoiding Jabiru’s “mistake” of having them at opposite ends of the crank.

I hadn’t seen that aircraft before. I’ve always liked Rutan designs, but most were very impractical for our type of flying. This one looks to have lots of potential, except for those pesky low wings getting wacked by bushes, sheep and roadside guideposts.

Looks good; if I was building, it would be on my shortlist.

I carried a camera for most of my life, ready for Yowies, UFOs, etc, but saw narry a one.

That proves nothing; I’m still open to evidence, but skeptical- especially about the timing of this supposed US openness.

Could this be just another distraction from what American authorities are really up to?

Good thread and good advice. Ground smoothness is damned hard to judge from altitude, even when it’s chewed down during a drought. Even a smooth-looking pasture can be ruff as guts; tussocks are big bumps. Turb’s line about driving across a paddock at speed is good advice.

I know farmers who fly; the prefer to land on roads.

Glen you might be able to advise me; I’m at the airport getting my plane ready to fly  for the first time in a year. Instead of just tossing my SE2 into the pouch under the window, I’m about to mount it properly. After removing the suction cup, there’s a neat plastic bayonet base, ready to screw or rivet in place.

I have only two viable locations, neither near my compass, which swings 10 degrees when the SE2 is near (I guess that’s the metal mounting bolt).

The first above my right forearm just under the window, where it can “see” half the sky, but forward view is through my plywood instrument panel.

The second site is under my canopy, with a wide view of the sky; trouble is, view forward and up is covered by a 30 mm wide aluminium strip. Is it likely that the internal aerial can see either side of this metal barrier?

I’m taller than that and fit in even the smallest Jabirus. Skyfox is too damned small.

Good morning Balázs. 

Your installation looks neat, but those big leaks need to be plugged.

I’d use Vinyl Ester resin if available, because it is more tolerant of heat than epoxy. To plug small gaps temporarily I just scrumple up some aluminium foil and jam in. Silicon rubber sealant might be useful around your ignition cables.
 

Those two big holes cut in your ram air ducts by the Jabiru factory are meant to provide cooling air to the crankcase and the rest of the engine, but they sure reduce the air pressure where it’s needed most: through the heads.
I closed mine off long ago. Likewise for the small ducts that direct cooling air towards the ignition coils. I plugged them. Now my coils are cooled by a pair of 25mm scat hoses that run directly from the front of the cowl. That cooling air probably helps cool the rest of the engine.

You could make a small fitting out of sheet aluminium to plug the air gap between the two tappet covers. It could be held in place by the two nearest cap screws.

From your pictures, it’s not clear if air passing through your oil cooler exits separately, under the cowl. It’s prefered to do this, so there’s lower air pressure under the engine, which help suck more cooling air down through the fins.

2 hours ago, facthunter said:

There was certainly NO SHORTAGE of weird designs but many were dangerous. It's understandable to want to produce something revolutionary and become famous and live the good life.

Some of these innovations were more acts of desperation by nations beng defeated- both German and Japanese.

2 hours ago, facthunter said:

Over time there have been many designs that were death traps and some just a bit harder to manage and with good training went on to be very successful. It doesn't usually happen by accident though . Nev

Nev I realise what you meant by that, but it could be argued that some progress was made by accident: some wartime deathtraps killed more test pilots than enemies. Perhaps each accident fed improvements in design and procedure. 

2 hours ago, Marty_d said:

Has anyone had luck sourcing fuel on/off valves? Inline that is, just for a safety "off" in the cabin in case of fire etc.

I found some inexpensive ball valves at a motorcycle shop. 
Two mounted next to my right knee.

38 minutes ago, facthunter said:

 A slight downhill and you'll float forever. Not good for GUSTS either. Needs spoilers.. I've encountered Jab owners who switch the engine off on short strips .Nev

Those spoilers that pop out vertically on sailplanes sure do the job and shouldn’t be too hard to retrofit on some designs.

They could be deployed while parked in windy conditions- better than tying a plank of timber along the wing!

I habitually warm up my Jabiru engine with a couple of fast runs along the strip (it’s usually pretty quiet).

At 2000rpm it will lift off and fly in ground effect. The plurry thing won’t land unless the idle is around 650.

I’ve heard that Jab engines wth EFI will idle happily at 350.

2 minutes ago, RFguy said:

How do people stay current on this stuff and only fly once a month in perfect condix ?

Most of us probably don’t. Few have the luxury of a quiet strip which they can use when the wind is just right. Then there’s the landing fees, which seem to have reduced circuit training.

I know one bloke who does hundreds of circuits, just to perfect his skills. Must be expensive.

1 hour ago, facthunter said:

I presume you mean run out of adjustment? You have to bleed the oil out of it to check that.

I guess that’s what they meant. 

1 hour ago, facthunter said:

My choice would be roller followers with manual adjustment.  Nev

My preference also, but I have to soldier on with what I have. Converting it to manual adjusters is not simple and I doubt the parts are still available.

9 minutes ago, facthunter said:

I don't know what rotated means in your context. Do you mean swapped or made to rotate (which can be done with special washers" Hydraulic lifters often use stronger valve springs also increasing loads.  Nev

Sorry Nev, not swapping. I mean turning each valve stem to make sure the lifter isn’t jammed solid.

36 minutes ago, facthunter said:

The advantage of manually adjusted valve clearances is you get an indication of this happening. With hydraulic lifters it's masked.  Nev

Nev this was discussed on the Jab/CAMit engine forum, where it was recommended that the valves on hydraulic heads be regularly rotated to ensure there’s clearance. A fiddly job, but well worth it for peace of mind.

Good morning Balázs, it’s 3am here and I cannot sleep.

A few more comments: according to Table 1 (below) your engine is a much later model than your friend’s. Yours would have the latest Flywheel bolt improvements, his does not, unless it has been upgraded. I presume he is aware that his flywheel attachement bolts need to be checked regularly.

As mentioned before, your propeller bolts don’t inspire confidence! Fixing that problem would be my first priority. 

I see you have a wooden/composite prop. It’s probably more efficient than the original wooden Jabiru prop that I have. I don’t know the recommended mounting for your type, but for my old wooden prop, each bolt requires four pairs of belleville washers as shown below. I believe these allow a small, natural amount of expansion and contraction of the wood, without crushing the fibres.

Note the even bolt lengths and excess threads clear of the nylock nuts.

(When installing longer bolts, I wouldn’t fit a used nylock nut for a critical job like holding on the propeller- I’d fit new ones.)

You’ll notice I have to remove the spinner to inspect prop bolt tension. Your setup, with nuts visible behind the drive plate, might be better in that regard than the standard Jabiru props installation, as seen below:

Below is evidence of how hot my cylinder heads have been; I wouldn’t like it any darker:

One way to keep them cooler is to ensure all air that enters your ram air ducts has to go through the cooling fins. I see you have what appears to be a large leak here:

17 hours ago, onetrack said:

The jet is a USAF, Convair F-102 Delta Dagger…

I thought I’d seen one before; according to my 1960s Time/Life book Flight, it was the first jet redesigned to the Area Rule, which reduced drag significantly.

Convair F-102 Delta Dagger - Wikipedia

EN.WIKIPEDIA.ORG

27 minutes ago, Balázs Dianovics said:

Here, of course, I still have a question: if I can only do this at max speed, do I still not produce more heat than what the excess speed means in cooling?

Don’t quite understand your question, but remember that increasing your airspeed has a considerable impact on cooling. ((I believe that if you double velocity, the pressure is squared.)

Summary: fix any small air leaks, get more air thru the oil cooler, go faster when climbing. 

Landing with about ten knots tailwind, on what is probably a short strip.
Maybe terrain precludes an approach from the other end.

9 hours ago, Balázs Dianovics said:

…since the coller is about 3-4 mm from the wall of the oil pan, I will try to adjust it with a small modification, to see if it helps with the development of air flow.

I guess “coller is meant to be “cooler”. It’s a good idea to make only one change at a time before testing, so you can be sure of the effect.

9 hours ago, Balázs Dianovics said:

Also, I lighten the aluminum body of the side coller so that if I gain a few millimeters for the outflow there, it might also mean 2-3 degrees Celsius. It has also been closed from the side on the oil tank. Also, I hope to be able to change the oil later without removing the cooler this way.

You should change the oil every three months, so mounting the oil cooler out of the way seems a good idea.

9 hours ago, Balázs Dianovics said:

Also, it seems that they significantly raised the collar from the engine so that the air can pass through and at a more perpendicular angle.

That sounds like a good idea, even if it means modifying that nice neat engine cowl.

9 hours ago, Balázs Dianovics said:

The weather in our country stays around 37-40 degrees Celsius even in summer, so I think it should still be able to handle that. What did you think of this?

That’s hot. Your Jab engine will need lots of airfow in those temperatures, so you need to climb out at a low angle, higher airspeed. 

9 hours ago, Balázs Dianovics said:

I didn't find anything on the manufacturer's instructions for running in, and I don't know how long it can take and how to do…

Try this site:

Engine Run In - Jabiru 2200 Instruction And Maintenance Manual [Page 74] | ManualsLib

WWW.MANUALSLIB.COM

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Jabiru 2200 Manual Online: Engine Run In. When built, the Jabiru engine is run in on a DYNOMOMETER and cooled with fan driven air. In the absence of a DYNO controlled run, engines can be run-in in the...

As mentioned by someone earlier, your propeller bolts look dodgy!

They should all be the same length and nylok nuts are required to have at least 1.5 threads exposed, to ensure it’s secure on the bolt.

10 hours ago, RFguy said:

There is probably still a bucket of thrust at 2200 RPM.

Good point, RF. It took me ages to get my Jab 2.2 idle set properly. Too low and it would stop on late final as airspeed dropped off. A couple of hundred extra rpm kept it running, but made the landing considerably longer.
Getting the idle screw right was the key.

On 17/7/2023 at 6:05 PM, skippydiesel said:

Its good piloting manors, to expedite your exit from the active runway, particularly on a RPT air field - Fly down  the  runway in ground effect, cut power just before exit.

Good point for those of us accustomed to having a quiet runway to ourselves.

I once landed at the start of Gunnedah’s long main strip, then realised I’d have to taxi a kilometer to the exit!
I’d made the normal calls, but noticed a big twin moving out onto the blacktop. Another call and the pilot finally noticed me, with a “gee you’re little!”.

30 minutes ago, Balázs Dianovics said:

Angle and insulation of the cooler: The device is noticeably turned downwards (toward the ground), and I am surprised if the air passes through it properly, although it is diverted from the inlet opening with a rubber band and the leakage at the bottom is solved with a sponge, in the end maybe the back pressure forces the air into the slats, but I am surprised that the front of the crankcase is almost behind the entire surface. 3 mm close. So as if I were to mount the refrigerator on the wall, I don't know how much draft it can create, but in principle it is a "factory" solution.

How much air can get through your oil cooler (is that what you’re calling the “refigerator”?) You might have to increase clearance from the engine sump and ensure no air leaks.

30 minutes ago, Balázs Dianovics said:

The speed of ascent was variable during the tests, but kept between 100-115 Km/h.

That might be your biggest problem; that’s only 54 to 62 knots- a bit slow. 
Can you test it at 120 km/h? That would be my minimum climbout speed to prevent overheating. (We hear lots about Europe’s heatwaves, so you might be operating in air even hotter than an Australian summer!)

30 minutes ago, Balázs Dianovics said:

Oil should cover the lowest, rippled section of the Jabiru dipstick.

Just make sure you have the recommended amount. (They say 2.2 litres but mine won’t even take two bottles of Shell 100+; the Canadian suppliers use those strange medieval measurements favoured in the USA. I think two bottles is about 1.9 litres).

Don’t forget that, if your ram air ducts leak any air, you’ll have problems.