Guest Ornis Posted December 2, 2014 Posted December 2, 2014 The heads of ARP bolts won't fit in the new crankshaft, 3/8" SHCSs only. Assemble and tighten capscrews comfortable firm without grease. Remove screws one at a time and apply a little grease to the end of thread. Torque to say 30 N-m. Back off and retighten each to say 40 N-m, diagonally; repeat to say 45, then to 50 N-m in a circular fashion. 50 N-m feels convincingly tight; it wouldn't be easy to tighten a capscrew more, unlike a bolt. 50 N-m (37 ft-lb) is well with the specified range, even 40 ft-lb (Sorry about the mixed scales, just convenient numbers I remember). I very much doubt there's any significant variation in the torque or the elongation with a quality wrench, even 10% more would still be safe. The benefit of using grease instead of Loctite 620 is you can check the joint again at any time. Years ago we replaced the vacuum drive with a steel spacer and placed a thick steel spreader under 5/16 ARP bolts, 50 N-m with grease. This joint lasted for maybe 600 hours. When the engine was disassembled following failure of an exhaust valve, there was little trace of "gunk" on the surface of the aluminium flywheel, unlike earlier (Jabiru assembly). I choose to go with the new crankshaft only to be sociable. The old joint without dowels was fine, the dowels followed a typical misdiagnosis of the problem: Insufficient friction. I was told I was buying an aeroengine that would go to 1000 hours and then need an inexpensive top-end overhaul, that some Jabiru engines were certified and this was "the same". I believed the man. Now I know better. The flywheel joint was designed with soft aluminium in the "sandwich" and poor clamp. Failure was inevitable and predictable. Now all the aluminium has gone - the aluminium flywheel has a steel centre - there is no rational reason not to torque to 50 N-m or more.
facthunter Posted December 2, 2014 Posted December 2, 2014 Holden in Australia developed a product to eliminate the inconsistency of human application of a "Loctite type product with the torqueing of various bolts in the front suspensions of their later cars. It was a "paint" that was applied to the threads of the bolts during manufacture. When the bolt is inserted into the threads small bubbles containing a locking compound are fractured and the compound is applied to the threads in the correct amount and evenly. Not all bubbles are fractured and consequently the bolt permits some retorqueing. Nev 1
geoffreywh Posted December 3, 2014 Posted December 3, 2014 Yup, That's been quite common for some time. Especially BMW and Triumph bikes with those Torq heads (which I have a healthy dislike for).... Not much happening on the Casa/Jab front is there?
gandalph Posted December 3, 2014 Posted December 3, 2014 ... Not much happening on the Casa/Jab front is there? I was in Canberra this afternoon and and as I walked past the CASA offices in Woden I thought I could hear the sound of furious back-pedalling, but then again it might have just been the storm front passing through..... 3 2 1
Guest john Posted December 3, 2014 Posted December 3, 2014 I can't see studs as offering any improvement. There is a limit to how many holes you can put in a small dia shaft and torque them up without distortion, or weakening of the shaft. (Like a telephone dial)Torque wrenches should be recalibrated regularly. I do it any time some thing is critical. There would be a big variation with lubricants. You should specify a new torque for using one. If you torque a lot of bolts you can FEEL when they have gone past the elastic limit indicating already stretched too much previously?? use NEW ones each time in critical applications. Nev.[/quote I was in Canberra this afternoon and and as I walked past the CASA offices in Woden I thought I could hear the sound of furious back-pedalling, but then again it might have just been the storm front passing through..... I was in Canberra this afternoon and and as I walked past the CASA offices in Woden I thought I could hear the sound of furious back-pedalling, but then again it might have just been the storm front passing through.....
Guest john Posted December 3, 2014 Posted December 3, 2014 What you may have experienced this afternoon Gandalph as you were walking past the CASA office is probably a lot of BULLSHXT coming from within the office & you were lucky that none of this SHXT hit you in the face.
motzartmerv Posted December 3, 2014 Posted December 3, 2014 I flew into Canberra on Saturday. Approach asked me if the aeroplane i was flying had a jab engine :) Just kidding. They wernt overly receptive, I senced major 'tude' from the controllers. Was unusually .... Noticeable...
gandalph Posted December 3, 2014 Posted December 3, 2014 I flew into Canberra on Saturday.Approach asked me if the aeroplane i was flying had a jab engine :) Just kidding. They wernt overly receptive, I senced major 'tude' from the controllers. Was unusually .... Noticeable... That's cause they all fly Jabs & they're bit cross with you... Just joking. It's been a while since I flew into Cbr. Most of the tower guys were always pretty good but there was one....... Well, there's always one in a group. But that was in my Cessna days and I always felt that he thought we were taking up his time when he could've been talking to important people in REAL planes. I know I got some VERY long "continue downwind" instructions from him. Could almost have qualified for my cross country on some of them. 1
kaz3g Posted December 3, 2014 Posted December 3, 2014 I flew into Canberra on Saturday.Approach asked me if the aeroplane i was flying had a jab engine :) Just kidding. They wernt overly receptive, I senced major 'tude' from the controllers. Was unusually .... Noticeable... What were you flying, Merv? It's one of the few places I haven't flown into. Nearly got there when the big meeting was called but ended up going road because the weather looked iffy. Kaz
bexrbetter Posted December 3, 2014 Posted December 3, 2014 I was in Canberra this afternoon and and as I walked past the CASA offices in Woden I thought I could hear the sound of furious back-pedalling, but then again it might have just been the storm front passing through..... A couple of recent complaints about the occasional off topic posts just pales to the life giving humour that springs out of know where and makes visiting the forum worthwhile. There's not many of us here who wouldn't have a good laugh together over a beer and a snag at the end of the day, kind of like Ralph E Wolf and Sam the Sheepdog clocking off after work after trying to kill each other all day long in the cartoons. 1 1 1
motzartmerv Posted December 3, 2014 Posted December 3, 2014 Was in a sportstar kaz. Rough as all get out as usual.
vk3awa Posted December 3, 2014 Posted December 3, 2014 Government response to aviation review http://www.warrentruss.com/portfolio.php?id=2556
facthunter Posted December 3, 2014 Posted December 3, 2014 Canberra was RAAF airport controllers, like Townsville and Darwin. there used to be a few subtle distinct differences between them and the civvy ones. Nev
facthunter Posted December 3, 2014 Posted December 3, 2014 Sounds like waffle about obvious motherhood statements as normal. Nev
turboplanner Posted December 3, 2014 Posted December 3, 2014 The key will be in the ones being worked on, and not accepted.
Camel Posted December 5, 2014 Posted December 5, 2014 Jabiru have released a Service Letter JSL 014-1 . I have no faith in Jabiru and look forward to Camit making advances as they are proactive at resolving faults and improving poor designs. 1
dmech Posted December 5, 2014 Posted December 5, 2014 Jabiru have released a Service Letter JSL 014-1 . I have no faith in Jabiru and look forward to Camit making advances as they are proactive at resolving faults and improving poor designs. Jabs letter , all true, fuel aint what it used to be . We should have mtow of 700 kg, so engines could be run on lpg mutch higher octane 1
facthunter Posted December 5, 2014 Posted December 5, 2014 You would get much less mixture variation. Nev
Camel Posted December 5, 2014 Posted December 5, 2014 Jabs letter , all true, fuel aint what it used to be . We should have mtow of 700 kg, so engines could be run on lpg mutch higher octane Well why are vehicles on the road no giving similar problems to Jabiru engines. I'm afraid cars have never been so reliable and effient as they are now even with current fuels. 1 1
turboplanner Posted December 5, 2014 Posted December 5, 2014 You obviously haven't had an experience yet. I haven't had any mechanical failures, but I'm fast finding petrol shandied with ethanol is an operational disaster unless you get excited about draining every tank on your property within two weeks of putting petrol in it. I'm finding a very stubborn gum-like substance in air orificies. 3
SDQDI Posted December 5, 2014 Posted December 5, 2014 Premium isn't exempt from that either, I noticed today some gummy residue in a clear filter that has only been two weeks since last used 1
turboplanner Posted December 5, 2014 Posted December 5, 2014 I suspect this is going to build into a national scandal. 1
Thruster87 Posted December 5, 2014 Posted December 5, 2014 Latest SB's http://www.jabiru.net.au/eula/eula.php?u=/Manuals/Engine/JSL007-5_Fuel_Guidance.pdf http://www.jabiru.net.au/eula/eula.php?u=/images/JSL014-1_Jabiru_Cylinder_Head_Inspection_4.pdf
kaz3g Posted December 5, 2014 Posted December 5, 2014 Was in a sportstar kaz. Rough as all get out as usual. I flew one at Parafield years ago. Seemed quite responsive and relatively easy to land. But I have since heard stories of weak nose gear which is not uncommon in RAA machines. I know RVAC had one and there were mixed reports. What are your thoughts? Kaz
motzartmerv Posted December 5, 2014 Posted December 5, 2014 Spotstars are nice little aeroplanes. They fly beautifully, no vices. I've never had an issue with the nose gear. We has used a few over the years and they have always stood up to the treatment. They can be a little squirmy on the ground so you need good feet, but nothing a tail wheel driver would find challenging. Very well built aeroplanes:)
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