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G2066 doesn't look too graceful in this pose...

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  • I came accross this ad in another forum which might be of interest. It seems this guy has a whole pile of new and used parts for the 1.8 litre soobs. Not sure where he is tho.[]http://www.homebuiltairplanes.com/forums/showthread.php?s=&threadid=2055Flying the wrong side up in Canada

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    • Well,Some good news at last.I went and saw [chainsaw] Bob Jumeau who flies at the same club as I last week end. He took one look at the blades and said they should be repairable.. subject to an inspection by Jack Allen who manufactured them. I spoke with Jack and he said that the blades can take a hell of a beating before they are marginalised. It would appear that the skins being crinkled may be the thing that is holding the blades out of shape at present. The magnitude of the bend on the worst blade is: bowed back 1/2" and down 3/4". It would appear this is within the range of bowing that can be encountered on the spars fresh out of the extruder, and it seems that they have to be straightened before the skins are mounted on them and bonded into position.. sounds hopeful and I'll be checking it out with Jack this week end.Mr Horan, you said you have a selection of push rods... would you have one of 231 mm length?The nose wheel should be easy to fix, it needs a bracket made up - this time in steel.Looking a little brighter..Nicholas TomlinAlarmist - www.alarmist.com.au - we scare for you

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      • Well,Some good news at last.I went and saw [chainsaw] Bob Jumeau who flies at the same club as I last week end. He took one look at the blades and said they should be repairable.. subject to an inspection by Jack Allen who manufactured them. I spoke with Jack and he said that the blades can take a hell of a beating before they are marginalised. It would appear that the skins being crinkled may be the thing that is holding the blades out of shape at present. The magnitude of the bend on the worst blade is: bowed back 1/2" and down 3/4". It would appear this is within the range of bowing that can be encountered on the spars fresh out of the extruder, and it seems that they have to be straightened before the skins are mounted on them and bonded into position.. sounds hopeful and I'll be checking it out with Jack this week end.Mr Horan, you said you have a selection of push rods... would you have one of 231 mm length?The nose wheel should be easy to fix, it needs a bracket made up - this time in steel.Looking a little brighter..Nicholas TomlinAlarmist - www.alarmist.com.au - we scare for you

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        • Well,Some good news at last.I went and saw [chainsaw] Bob Jumeau who flies at the same club as I last week end. He took one look at the blades and said they should be repairable.. subject to an inspection by Jack Allen who manufactured them. I spoke with Jack and he said that the blades can take a hell of a beating before they are marginalised. It would appear that the skins being crinkled may be the thing that is holding the blades out of shape at present. The magnitude of the bend on the worst blade is: bowed back 1/2" and down 3/4". It would appear this is within the range of bowing that can be encountered on the spars fresh out of the extruder, and it seems that they have to be straightened before the skins are mounted on them and bonded into position.. sounds hopeful and I'll be checking it out with Jack this week end.Mr Horan, you said you have a selection of push rods... would you have one of 231 mm length?The nose wheel should be easy to fix, it needs a bracket made up - this time in steel.Looking a little brighter..Nicholas TomlinAlarmist - www.alarmist.com.au - we scare for you

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          • All good news Nick. Hope it works out for you without costing too much. We got to keep our dreams alive mate.Graeme.

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            • All good news Nick. Hope it works out for you without costing too much. We got to keep our dreams alive mate.Graeme.

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              • All good news Nick. Hope it works out for you without costing too much. We got to keep our dreams alive mate.Graeme.

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                • Just a refresher on this one fellas...I was talking to a bloke who dabbles in car engines and drives a nice renovation of a HQ Ute.I explained to him the demise of my engine and he made the observation that valve push rod failure "sometimes" through to "usually" is the result of the engine over revving, and he asked if it had ever over revved?Yes, is the reply - it did at one point for a short period of time.This was after I had fitted the new redrive and was running experiments on the belt tension to see what would be comfortable for the redrive, at one point [as I may have noted before] the engine was doing about 6200 revs when the belt was slipping due to my having adjusted it to be too loose. I can only assume this was the cause or a part of the cause for the push rod to fail.I notice now after getting the engine going again that it has a vibration which was there when I lost power, one of those annoying vibrations that feels like you"re sitting on an orbital sander. I"ve stripped it down so it is just running the flywheel, so I can discount the prop and driven pulley in the redrive as being the cause of the vibration as it is there without them. I don"t recall it being there after I installed the redrive so I can only assume that the over-revving has done other damage to the engine, and it is not something I"m going to screw with knowing what vibrations of this kind do to aluminium structures.So, I think for simplicity I"m just going to reblock it with another EA 81 engine, rebuilds are not worth the trouble so I"ll probably go to Cardiff Automotive and grab another donk, hopefully a smoother version of the one I"ve got.So, I"m suggesting an AD for all Subaru EA-81 powered gyro"s:Where the engine revs for this particular engine exceed manaufacturers rated revs [I"m suggesting 5600 RPM in the absence of any other knowledge] the engine should be assessed for damage to all internal componentry. Any pilot who experiences an increase in the vibration of these engines [Either sudden or otherwise] should have the engine assessed for damage which may lead to an in flight loss of power through the failure of the valve push rods particularly and/or any other componentry which may be stressed by such an event [Con rods, gudgeon pins, crank shafts, cam shaft, etc].Over-revving may occur as a product of any number of events but the most likely of them are:Badly adjusted belt tension on a belt redrive.Gearbox Failure.Crank Shaft Failure.Underpitched Propeller.Propeller strike resulting in a sudden loss of engine load - blades being shedded.:End of AD.So, the costs are adding up for me, even more and more, the joys of flying...Has anyone got an EA-81 in good order for sale? [I"m using a gyro-bits redrive which may not fit any other engine so I"m stuck with an EA-81]Cheers,Nick.

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                  • G"day Nick,I thought your drive had a toothed belt. If that"s the case, how did you get it to slip without ripping the teeth off it? If it"s not the case, question answered.Cheers

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                    • Nick,get some one who knows ea81"s to look at it ... I"d be interested to know what the problem is or was. No one there in the ACT that can diagnose your problem eh? Stupid question but have you completely stripped the motor since you had the problem?rotor

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                      • Fred,My guess is that if the belt is loose enough it can climb over tooth by tooth from the slack side, the facts of it were that with the belt properly engaged the revs would max at about 5400, but most certainly not 6000+ as with it adjusted loose. The problem of this is that you may adjust it and ground test it but still not be subjecting it to full torque as you will in flight, then you go for a test fly and discover that it isn"t quite right.Rotor,Thanks, not a stupid question at all. I had replaced the push rod to see if it would go again without this knowledge on tap, so you tend [ Rather "I" ] tend to fix the most obvious problem, then you get down into the in depth diagnosis of the "real" problem.. after you find that the early and "most obvious" fix didn"t really fix the problem at all.The bottom line of this lesson for me is that any engine failure, just like pilot failure, is as I saw in an aviator"s magazine an issue of the "cheese holes all lining up at once" - here"s all my cheese holes --> 1st cheese hole - having a gyro, 2nd - installing a redrive, 3rd - fiddling, 4th - flight testing & damage event [ ignorance point and critical risk event ], 5th - flying after damage event in ignorance of same [Failure to note change of vibration and attribute it to a major risk issue], 6th - flying in unfamiliar surrounds [ Manilla, not Denman ], 7th - Having to fly a long downwind due to other inbound aircraft, 8th - outlanding after engine failure [All nice and controlled up to this point, it would have only cost an inspection to now], 9th - flop over in paddock [Stupid! Major cost event incurred here.]. So, the bottom line is "Pilot Failure", nothing to do with the engine at all.If you"ve had an engine failure of a dramatic kind, as this one was, a strip down and check of tolerances may be a really good idea, especially if you don"t want an unexpected repeat of same over any territory, never mind tiger territory.The clue, in retrospect, was the vibration while the engine was at flight torque and power. So if your engine is not smooth, please check it out.Cheers,Nick.

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                        • Gents,A progress report after some years of neglect.. G2066 is currently sitting at my hired office site - about 1/2 an hour away from home. At the moment I"ve got the manifold off it as the gasket to the water jacket section is leaking - On attempting to start it one day after it had been running for a while I noticed water coming out of the exhaust. After some diagnosis I found that the gasket between the water jacket and the inlet manifold on cylinders 1 and 3 was leaking and passing water into the cylinders.I will do this rehabilitation some justice soon.. when someone sends me a "round-to-it"

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                          • More progress - and a warning to those who fabricate their own inlet manifolds...A couple of weeks ago I was tuning the engine up and stopped it due to the entry of another person to the area of operations - he was attracted by the noise and came to enquire.I explained to him what this "helicopter" was and gave him the appropriate web sites to look at. After he left I resumed my activities only to discover water being discharged from the right bank exhaust. The gasket had failed - due to the manifold warping with heat from welding, additionally it was pinholed with corrosion. Not happy :-(I"ve elected to do it differently now. I will be acquiring 2 weber 34ICH carbs and putting one on each head with a flexible balance tube joining the heads under the carbs.Any suggestions?Nic

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                            • nic, just found this post and started reading from the beginning[ good place to start] did you find the origanial problem, loss of rpm back 3600,?

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                              • Gents,Thanks for your suggestions:-)It hasn"t Been neglected for five years as suggested but browny"s suggestion is a good one. I should replace the push rods as well. I have been maintaining it by running it periodically, it was just that the manifold was a cooked up thing that was due for replacement due to corrosion and some degree of warping in the base plates as a product of temperature differentials across the metal it was made from.What caused all this grief was my stupidity in failing to stop after the out landing - make sure you do stop and tie down, no matter what... don"t even bother to taxi. Just tie down and take a break, or, you will break something - at $1000/sec it is worth it!What caused the push rod to break was over revving the motor - which I was ignorant of. If your motor goes over 5000 - 5500 rpm I would suspect it would fail in the near future, check everything!!!

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