SDS No More Leak Induction Tube Solution For Lycomings

Discussion in 'Supplier / Manufacturer Announcements' started by rv6ejguy, Jun 2, 2018.

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  1. Jun 2, 2018 #1

    rv6ejguy

    rv6ejguy

    rv6ejguy

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    These use a COTS silicone O-ring to seal the tube flange against the head, eliminating the flat gaskets which have been known to leak and cause grief on occasion.

    Like our SDS valve covers, these billet flanges tighten down flat with even, metal to metal contact so there is no more flange distortion or "give" in the gasket over time.

    They will come as a kit which also includes the O-rings, silicone hoses and constant tension clamps to replace the factory parts. For carbed engines, we'll supply new standard rubber hoses. Will be available for both 1.5 and 1.75 OD induction tubes, in gold or red anodized finish.

    I'll try to get a photo of the complete kit this weekend.



    lycflange18.jpg
     
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  2. Jun 2, 2018 #2

    Toobuilder

    Toobuilder

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    After trying several different gaskets including paper, composition, silicone and even dead soft copper, I threw a rough O ring idea at Ross and sure enough, he took it and improved it. Some prototype parts showed up in my mailbox and I promptly installed them on the RV -8. Keep in mind the -8 is an angle valve, requiring the added step of cutting and re welding the tubes to replace the flange clamps. Easy, but not required on the parallel valve engines.

    Anyway, once the new clamps are on the tube, you simply install the O ring over the inner retainer and slip the assembly in place between the head and clamp. Snug up the bolts to spec and you are done. Unlike with the paper gaskets, it is impossible to bow the retainer or over compress the O ring. It's simply a install and forget thing.

    There have been many attempts to "fix" the induction leaks at the head over the decades since the Lycoming was designed - this is finally the one that works.

    [​IMG]
     
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  3. Jun 2, 2018 #3

    TFF

    TFF

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    Thats pretty cool.

    Solve exhaust leaking and the world is yours. Intake and valve covers, check.
     
  4. Jun 2, 2018 #4

    rv6ejguy

    rv6ejguy

    rv6ejguy

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    lycdlange22.jpg

    Here's what the whole kit looks like.
     
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  5. Jun 3, 2018 #5

    Dan Thomas

    Dan Thomas

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    Trying to see if that O-ring contacts the tube's flange face. That shiny ring: does it just fit into the O-ring to prevent its being sucked into the induction? Or is it sitting on the tube flange and supporting the O-ring?

    Those intake gaskets do frequently leak. Often see blue stains around them. And once in a while I have found chunks blown out of them, creating a really serious leak. If a pilot, while checking the mags during runup, goes to "Off" and then back on again, he will cause an explosion in the exhaust system as the raw air/fuel that filled it while the switch was Off ignites. Any cylinder that is at TDC on the exhaust stroke, where both valves are open, will suffer considerable concussion that can blow that intake gasket out. Lean backfire can do the same thing.
     
  6. Jun 3, 2018 #6

    rv6ejguy

    rv6ejguy

    rv6ejguy

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    The O-ring sits on the tube flange face. The silver ring captures the O-ring so it can't go anywhere and establishes the proper squish on the O-ring.
     
  7. Jun 3, 2018 #7

    Dan Thomas

    Dan Thomas

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    Excellent. Keep it up. There are plenty of places where O-rings would fix a lot of headaches. The magneto gasket is a classic hassle; anytime you loosen and rotate the mag to retime it, you risk tearing the gasket because it sticks. But coming up with an O-ring fix without machining the mag flange or accessory case is more difficult. Any adapter in there moves the mag back, partially disengaging the gear teeth.

    That dumb gasket setup on the oil disptick tube where it screws into the case is another case for an O-ring. And anything that uses the copper crush gasket, like the oil suction screen fitting.

    Silicone cylinder base O-rings would last longer. The current O-rings are probably Viton and after a few years they take a set and start seeping.
     
  8. Jun 3, 2018 #8

    BBerson

    BBerson

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    Gasoline melts silicone. (the stuff that comes in a tube) I found silicone goo in a gascolator where a mechanic had tried to make a silicone gasket.
    Is this a fuel resistant silicone?
     
  9. Jun 4, 2018 #9

    rv6ejguy

    rv6ejguy

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    The design is aimed at fuel injected engines first but for carbed engines, we supply Viton instead of silicone O-rings. These go with non-silicone induction hoses as well, as stated on our website.
     
    Last edited: Jun 4, 2018
  10. Jun 7, 2018 #10

    rv6ejguy

    rv6ejguy

    rv6ejguy

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    Response has been very good. We sold out the first batch in 2 days and I'm picking up another run from the machine shop today which is half sold already.
     

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