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geoffreywh

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Everything posted by geoffreywh

  1. geoffreywh
    I wrote earlier that it looked " boxy" That was not serious critique. I think that the excellent, strong and easy to assemble box that you produced could be shaped as you wished, fleshed out with a fibreglass ( G forbid) turtledeck, canopy P51B style. and somebody elses "off the shelf " cowling. Don't get sidetracked by our comments, your idea was coming along very well.
  2. geoffreywh

    Resonance!

    geoffreywh replied to Bleve97's topic in Jabiru

    A 400hr engine that I wrote about was EXTREMELY stiff when hot. Probably would take a 10kg weight hung on a prop tip to move it. Since reporting that I did some investigation. Firstly Jabiru tell me that they no longer use loctite on thru' bolts (Hurrah!) Then I loosened the thru' bolts and retorqued to 30 ft lb, (some improvement in the prop feel. ) Then to 20 ft lb. Beautiful and end float now present. . Result? I propose Bulk engine strip and lessen main bearing shell "pinch" ...Note if you get hold of a prop tip and move it gently , i mean really gently, you should be able to feel (or hear) a very slight "loose " patch, That would be pistons rocking in the bore ( or a big end bearing gone!) If that very small movement is absent then the crank is being held tight.
  3. geoffreywh
    how odd. I have had two ANR headsets plugged straight into my Microair for years. Never a problem. Not with headset and intercom anyway...
  4. geoffreywh
    Not want to get too far ahead, but, the canopy always seems to be a stumbling block. Would it be possible to make the design fit an already available canopy|? ( does one exist? ) or better still a glass house canopy like WW2 American carrier planes. Or better still that that even , No canopy at all....
  5. geoffreywh
    It's looking very boxy. how about a turtle deck ( not to eat) and some fairings and stringers?
  6. geoffreywh

    Resonance!

    geoffreywh replied to Bleve97's topic in Jabiru

    the engine is 500 hrs from new. Absolutely certain the c/shaft is being pinched. pistons are not involved. Also zero end float on the crank. ( Crank pinched by thrust bearings... possible? ) How does c/case fretting happen with all those tight dowels? I have to remove heads for valve job. Or was it remove valves for head job? I'm now confused. As far as "Back to Bundaburg" goes. How will that help , it just came from there!................ My theory (for what it's worth) is that the new 7/16" bolts with 40 odd foot pounds of torque exert more crush on the crankcase (less stretch than the thinner bolts). When the case heats up and expands it is squeezing the crank. However, why that should not start happening during the warranty period is a mystery.
  7. geoffreywh
    I used to have a construction set remarkably similar to your concept. That was fun too. Well done, and thanks for the extra tail wheel work.
  8. geoffreywh

    Resonance!

    geoffreywh replied to Bleve97's topic in Jabiru

    sorry mate Lycomings and Continentals use "turned from solid" steel cylinders. NOT cast iron................. BTW I have seen recently a 2200 flat four that was free to turn when cold but extremely tight when hot. felt like it had siezed but with extra puff the prop could be moved. Fine again when cold....Thermal expansion and thru' bolts too strong? (7/16) what else would do that?
  9. geoffreywh
    I was going to add.............."and about as reliable" but I wont
  10. geoffreywh
    Didn't I see a Sopwith Something dropped from an airship?
  11. geoffreywh
    sorry mate , never seen a shattered rotor in 55 years of motorcycling outside accidents. "Shattering " steel rotors is absolute bull#### . Only cast iron discs will shatter . Steel will warp. "Stainless rotors in the wet " was a Jap syndrome , which was still far better than "Drum brakes in the wet" But then you drive within your capabilities? Same as sourcing bolts from Bunnings for any vehicular use. Madness. Anyone looking for AN stuff ans ending up at Bunnings is really silly. I have chinese disc rotors and they're great thanks
  12. geoffreywh
    Please do, if a carb floods it runs straight down onto the exhaust !
  13. geoffreywh
    The springs sold in Bunnies in individual white plastic packets are as good as any springs I have ever used. Made in USA. I have used them on many projects to great effect. Just get the right ones ! There is a HUGE selection of diameters/lengths and spring wire thicknesses. Just because something is cheap does not neccesarily mean that it's bad. i.e. Trelleborg tyres on Jabs'. Miccro air radios, I could (and often do) go on....
  14. geoffreywh
    please don't call me Shirley.
  15. geoffreywh
    If you read the manual it says that the bearing clearance is the MAIN goal. It is important that there is some bearing crush, the amount is of secondary importance........They describe how to "lap" the shell ends on wet and dry 600 to achieve tighter clearance at the expense of bearing crush. ...As I started with (journal #1 exactly 45mm ) 0.17 bearing crush and 0.10-11 big/end clearance. I deduce the big end eye is a bit big. Following the manual I now have correct b/e clearance and just over the minimum crush. All were similar. On dismantling the engine originally the b/e shells looked terrible. Waaay to much clearance. I'm ok with it now...............Just following orders...........BTW I don't use plastigage. I use mike and bore gauge..............Another interesting item came up today. Checking the ring gaps (new barrels and pistons) I came up with 0.43mm. on the first one. I Check the manual, it says " New piston rings usually measure 0.50 - 0.60mm !" with a maximum of 1.2mm. WTF does that mean? What are they supposed to be? My usual rule for a/c engines would be 4 thou per inch of bore. So my .45 is spot on.....I just worry about things like that........Especially as the manual also says . New cylinders MUST BE 107.5 mm long. My news ones are sweetly marked and measure 107mm. I can really do without this S***
  16. geoffreywh
    no. i reduced the crush to get smaller b/e clearance as b/e is more important according to the manual
  17. geoffreywh
    So, following the factory manual proves correct. you can reduce the "bearing crush" to reduce the bigend clearance. I set the big end clearance at 0.04-0.05mm and got a bearing "crush" of 0.05 -0.08mm which is exactly what I wanted. It did take an hour for each big-end. But that's ok. Concerning Jabiru engine assembly. It's not rocket science, it's not laboratory work, you don't have to normalise rod temps or anything extreme. Just Be Clean, Be Careful, Measure Carefully. Wear gloves ( graphite is a bastard to get off ) . Follow the manual and it will be fine.
  18. geoffreywh
    what ever the factory supplied! Did you check the clearance?
  19. geoffreywh
    Rebuilding a 2200 I find the big end clearances to high, Crank measures 45mm, big end eye 8-9 hundreths more. The b/e bearing crush is up around 17 hundreths. This is far too much. For both. The manual says ( as far as I can understand.) That removing material from the ends of the b/e shell will reduce the b/e shell crush (obviously) and as a side effect reduce b/e clearance. (not so obviously) . Does anybody KNOW if this is the way to reduce b/e clearance to the factory spec of 4-6 hundreths. Normally I would have given the rods to the machinist and he would resize the eyes for me. But Jabiru, being Jabiru, may be completely different. G
  20. geoffreywh
    I like Microair. I had a problem with mine. They checked and upgraded my radio, sent it straight back. The problem turned out to be the antenna, They went way past normal service and were extremely helpful, can't have better than that.
  21. geoffreywh
    are any aircraft ever weighed at a ramp check?
  22. geoffreywh
    you don't sleep do you?
  23. geoffreywh
    Bex...nose wheel or t/d? or both ( not at the same time please)
  24. geoffreywh
    I like Dick , He seems straight and a real bloke.......... He is a vocal member of the Stable Population group. Which , I believe is the ONLY way forward for Australia.....
  25. geoffreywh
    the guy in the video quotes a saying thus "as easy as riding a bike"....this is nonsense, the expression goes " as easy as falling off a bike" ...........get it right mate
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