Another through Bolt gone

[Camel]

Just to put some light on things, I have a Rotax 912uls and a Jab 3300. The 912 has over a 1000 trouble free hours ( except exhaust problems ) and the Jab has 180 trouble free hours, the Jabiru was using Shell w100 oil then W100 Plus up till 150 hours and at that point Leak down pressure test was not looking good and compression felt poor on hand rotation. It is now been on a lighter multigrade oil and is a major improvement and is very noticeable, several other aircraft owners that I am in discussion with are also showing good signs using lighter muligrades. So I suggest it has a lot to do with oil as this is a major factor on hydraulic lifters, rings sticking, valves breaking, valve guide wear and oil pressure. I was using only avgas but fill mostly with 98 unleaded but if I fill anywhere else I put in Avgas, so there is always avgas and a 98 cocktail in the tank. The oil before went very dark after going to a lighter multigrade and now is clean. The engine is very easy to start because of better compression and was difficult before. I do not know whether this is the fix for all Jab problems but am feeling confident that this is a likely simple remedy.

 

I am a Motor Mechanic by trade and am knowledgeable on aircraft engines as well, I did my apprenticeship on British Leyland / Leyland Australia and we told the factory engineers how to fix problems on some greats like the Morris Nomad, Marina, Kimberly and P76. Leyland went broke because they lost communication with their dealers and made design problems dealer problem with their buyer protection plan.

 

I have also worked on early Honda and Datsun and if there was a problem it was fixed and look at their product now.

 

I agree that Jabiru are not actively fixing problems or listening to anyone. I have had words in the past and have no more to say to them as I'm sure they think everyone who buys their product is just stupid. I also think that the Jabiru airframe is a good product but prefer the lower stall speeds of the bigger wings say the J250 compared to the J230 and the J170 compared to the J160 but they don't want to produce the J250 anymore.

 

 

[Guest Maj Millard]

No problem there Timbo, all in the spirit of hopefully lively constructive critisism. Your voice and opinion on the subject is just as welcome I'm sure as anybodys.....................................Maj...

 

 

[turboplanner]

Ausadvance, if you had been involved in any one of the number of forced landings listed from Pilot Notes, so not just lurid assertions, and you or your loved ones had escaped death or serious injury by the skinniest of margins, or if you had paid out thousands of dollars for training only to see several of the aircraft you trusted involved in forced landings, you might have had some empathy for the feelings of those who have been involved and aren't just spending a lazy Saturday afternoon when they comment. If you want to see anger, just taunt them a little more.

 

 

[Guest Maj Millard]

Camel, now that's what I call a constructive suggestion !...you may well be onto something there with the lighter-grade oil . The fact that the new oil went dirty, and then clean, indicates that it's possibly reaching areas that wern't reached before ?....or is that the rings have just seated a lot better, and your not getting the same amount of carbon past the rings to foul the oil...............................................Maj...

 

 

[turboplanner]

One friggin engine major - you need that to happen on a hundred before getting excited....Oh and 180 trouble free hours?

 

 

[Guest Maj Millard]

Turbo, At least this bloke sounds like he knows what he is on about, unlike the many owners who simply listen to the BS that the factory constantly feeds them !....without fixing a damn thing I might add...........................................................Maj...

 

 

[ave8rr]

It is now been on a lighter multigrade oil and is a major improvement and is very noticeable, several other aircraft owners that I am in discussion with are also showing good signs using lighter muligrades. So I suggest it has a lot to do with oil as this is a major factor on hydraulic lifters, rings sticking, valves breaking, valve guide wear and oil pressure. I was using only avgas but fill mostly with 98 unleaded but if I fill anywhere else I put in Avgas, so there is always avgas and a 98 cocktail in the tank. The oil before went very dark after going to a lighter multigrade and now is clean. The engine is very easy to start because of better compression and was difficult before. I do not know whether this is the fix for all Jab problems but am feeling confident that this is a likely simple remedy.

Camel, Thanks for your input. I had a J160 few years back. Built from a kit when we lived in Bundaberg and flown from there until sold in 2008. My engine was a 2200 with solid lifters and the earlier heads (thicker fins)and we had to do a top overhaul at 150 hours due low compressions. We ran that engine on Shell W100 from new.

Can you advise what type and grade of oil you are now finding is better? I am surprised you have managed to get the compressions back up with out any other work.

 

Cheers

 

 

[XAIRVTW]

So an Australian company produces an aircraft for sale in Australia which must not be operated in temperatures above 38C ??.

I was at Bathurst last weekend at YBTH Saturday 39 degree heat Sunday 37. There were plenty of Jabiru aircraft doing circuits & flying around all day. Horses for courses some people like them some dont.

 

 

[M61A1]

Camel, Thanks for your input. I had a J160 few years back. Built from a kit when we lived in Bundaberg and flown from there until sold in 2008. My engine was a 2200 with solid lifters and the earlier heads (thicker fins)and we had to do a top overhaul at 150 hours due low compressions. We ran that engine on Shell W100 from new.Can you advise what type and grade of oil you are now finding is better? I am surprised you have managed to get the compressions back up with out any other work.

Cheers

I wouldn't rule out some of the improvement arising from using the 98 octane mogas. Quality mogas has additives that reduce deposits in the combustion chamber. After seeing the build up (from avgas) in my engine (not a Jab), I have been using 98 mogas, and have no significant deposits as yet.

[Gentreau]

I was at Bathurst last weekend at YBTH Saturday 39 degree heat Sunday 37. There were plenty of Jabiru aircraft doing circuits & flying around all day. Horses for courses some people like them some dont.

I'm sure there are lots of people operating them outside the manufacturers recommendations, I was simply pointing out the terms of that particular recommendation.

 

 

[nong]

Camel, Thanks for your input. I had a J160 few years back. Built from a kit when we lived in Bundaberg and flown from there until sold in 2008. My engine was a 2200 with solid lifters and the earlier heads (thicker fins)and we had to do a top overhaul at 150 hours due low compressions. We ran that engine on Shell W100 from new.Can you advise what type and grade of oil you are now finding is better? I am surprised you have managed to get the compressions back up with out any other work.

Cheers

G'day av8RR. W100 is not the stuff for run in. This could be where your trouble started. 100...without the W is the traditional aviation run-in oil and is recommended as such by both the Shell and Jabiru. W oil is ashless dispersant and is not recommended for run-in in Shell technical literature. I just fitted a brand new 2200 to our J160. After two hrs shake-down it went Wagga Ayres Rock return on Shell Aero 100. After that flight, in went the W100. Oil consumption is negligible and most of that is only spat into the catch-bottle.

Cheers

 

 

[Guest Error404]

Aeroshell 100 for run-in period

 

W100 plus for continued use.

 

as per the AFM !

 

If I understand correctly, W100+ replaces 15w50.

 

 

[ave8rr]

G'day av8RR. W100 is not the stuff for run in. This could be where your trouble started. 100...without the W is the traditional aviation run-in oil and is recommended as such by both the Shell and Jabiru. W oil is ashless dispersant and is not recommended for run-in in Shell technical literature. I just fitted a brand new 2200 to our J160. After two hrs shake-down it went Wagga Ayres Rock return on Shell Aero 100. After that flight, in went the W100. Oil consumption is negligible and most of that is only spat into the catch-bottle.Cheers

I think from memory (2004) that we did use aeroshell 100 for the run in period. Was what Jab said to use anyway then went onto the W100.

This engine was being operated as per Jabiru instructions as we were right there at Bundy under their supervision including the build.

 

Cheers

 

 

[Guest Error404]

I know of around 25 Jabiru powered aircraft in my local area and only one of those made TBO. That one went to the factory for a top end overhaul and came out with a full overhaul as the crank case had been fretting. Chances are if your through bolts done break something else might!

 

 

[Sapphire]

I think the immediate effect of the lighter oil would be on the hydraulic valve lifters. Sludge is the no one enemy. I've quietened down many car lifters with half hour hot high speed run, which is the same as thinning the oil and that oil moving the sludge along. Hydraulic valve lifters:thumb down:

 

 

[Phil Perry]

Do they still manufacture the 8?

I really Don't know what they are putting in the Mk26 kit nowadays Motz, I only saw an early version up close, when they weere first imported and an example hadn't been com[pleted and flown then. . . ..

 

 

[Gentreau]

They now install Isuzu V6's and Chevrolet (I think) V8's

 

.

 

 

[fly_tornado]

didn't they 5100 used to catch on fire?

 

 

 

 

 

 

 

 

[Phil Perry]

They now install Subara V6's and Chevrolet (I think) V8's.

Thanks for that Clive.

 

 

[boingk]

I wouldn't rule out some of the improvement arising from using the 98 octane mogas. Quality mogas has additives that reduce deposits in the combustion chamber. After seeing the build up (from avgas) in my engine (not a Jab), I have been using 98 mogas, and have no significant deposits as yet.

Can second that - have switched from Avgas to Mogas in my A-65-8 powered Minicab and love it. Easier starting and seems to run very much smoother after 20 hours or flying time. Only downside is it leaves a slight soot deposit out of the exhaust, apparently this is common on Continental 65's run on Mogas though.

 

My point is that the last owner recommended it as it did not stick up the valves, nor leave as many deposits, nor cost as much. This was a fellow who had had the engine rebuilt from the crank out and wasn't afraid to take everything out and rework if needed, too; he knew what he was talking about.

 

Not a big fan of Avgas myself, especially in my little 65 which was rated for 75 octane and recommended to use 80 octane! Using 95 octane Mogas almost seems like overkill when you look at it like that.

 

- boingk

 

EDIT: Just for the record, I don't have a lot of faith in 'Aviation' branded oils. I'm heavily into motorcycle and automotive mechanics - maintain all my vehicles myself - and working with aviation oils is like taking a step back 50 years. Very conservative, very costly, very marginal. Yes, they work, but I believe there are better options out there. Personally I like the modern diesel oils such as Gulf Western 'Top Dog' 10W-40 or Dello 400 10W-40. Incidentally these oils can be bought for very reasonable sums when buying in bulk - I recently paid $90 for a 20L drum of GW 10W-40, for example.

 

 

[Guest SAJabiruflyer]

I wonder if anyone had tried, and had it make a difference, products like Slick 50 or the Nulon equivalent? Not recommended? I've whacked a bottle into every car I've owned. did they work in my car? I know a noisy lifter or similar in a Holden v6 never returned..

 

 

[Phil Perry]

Isuzu V6....

Thanks for that as well Arron . . . . .

 

 

[Gentreau]

Isuzu V6....

Oops, must learn to type what I've just read, thanks Arron :)

 

 

[Vev]

Guys,

 

You really need to be careful when comparing Aviation octanes to Mogas ... Mogas measured differently to aviation fuels. You also need to be aware that US Mogas is also reported differently to Aust mogas.

 

A very rough but simple conversion +\- a few octane :

 

US mogas to Aus mogas add 5 octane

 

Avgas to Aust Mogas add 10 octane

 

This is not exact but will give you a feel for the magnitude

 

As for using automotive engine lubes or additive packs ... There is so much complex chemistry behind designing an engine lube, you will be playing Russian roulette by departing from the manufactures spec. .. Just don't do it. If a major oil company recommends a product you can be assured its has been careful designed and tested to do the job and meet all the OEM performance specs.

 

Cheers

 

Vev

 

 

[M61A1]

Guys,You really need to be careful when comparing Aviation octanes to Mogas ... Mogas measured differently to aviation fuels. You also need to be aware that US Mogas is also reported differently to Aust mogas.

 

A very rough but simple conversion +\- a few octane :

 

US mogas to Aus mogas add 5 octane

 

Avgas to Aust Mogas add 10 octane

 

This is not exact but will give you a feel for the magnitude

 

As for using automotive engine lubes or additive packs ... There is so much complex chemistry behind designing an engine lube, you will be playing Russian roulette by departing from the manufactures spec. .. Just don't do it. If a major oil company recommends a product you can be assured its has been careful designed and tested to do the job and meet all the OEM performance specs.

 

Cheers

 

Vev

I have read a few articles on the evils of mogas, most of them speak of the poor quality control, but I think the main advantage of avgas is that it is designed not to cause vapour lock at altitude (something to do with vapour pressure). Since I tend to stay under 5000' amsl, I don't think too much of it. As for the oil, if it works in my aircooled bike, in traffic, with no cooling airflow, I am prepared to run it (I do tend to avoid diesel oils in petrol engines though).I agree with boink about most aviation products, there is much better out there, aviation just hasn't kept up. An example that comes to mind are the 2 greases used on the Bell 206, there are many better lubricants than them in general industry. I have also had a major oil company rep recommend(for a particular application) and sell grease that was totally inappropriate and caused a lot of bearing failures. If I wanted to find out the best oils, I'd talk to one of their chemists.