Starter O-Ring

Discussion in 'Maintenance Bay' started by Rob58, Oct 1, 2020.

  1. Rob58

    Rob58 Pre-takeoff checklist

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    Trying to find a part number and source for the o-ring that fits around the working end of a Delco starter, providing an oil seal between the starter and the starter adapter on an IO-520D. Delco starter is P/N 1108249. All help is appreciated!

    Starter O-ring.jpg
     
  2. Tom-D

    Tom-D Taxi to Parking

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  3. Bell206

    Bell206 Final Approach

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  4. Rob58

    Rob58 Pre-takeoff checklist

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    Yes, the AS3578-038 was the part number I found in the Continental parts book. Here's the dilemma: the AS3578-038 spec says the OD is 2.750, however the diameter of the starter nose is 3.250. Is it conceivable that they want me to use an undersized o-ring and simply stretch it to fit?
     
  5. Dan Thomas

    Dan Thomas Final Approach

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    The older TCM parts book number was MS9021-038. Plenty of aircraft maintenance shops will carry that part.
     
  6. Bell206

    Bell206 Final Approach

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    FYI: a lot of the older mil-specs are being replaced by SAE and AMS specifications. The AS3578 (SAE Aerospace Specification - AS) supersedes the MS9021 series o-rings and are pretty common at the retail level.
     
  7. Dan Thomas

    Dan Thomas Final Approach

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    I know that. I mentioned the older designation because a lot of aircraft shops will still have it in stock as the old number.