Hello all,

 Does it matter if the bolts that attach the engine mount to the fuselage go from inside the fuselage out or  from the engine mount through the firewall into the plane?

 I have the Viking 130 mount on a 650. I attached the mount temporarily today to help move from the basement to the garage,  The Viking mount needs about a 2 1/2 inch bolt.

  With the 10 degree angle on the front of the fuselage mount brackets I don't see how I'd be able to get a long bolt to go from inside out.  The AN6-7A in the Zenith plans work ok that way but they aren't nearly long enough.

What do you think?

Thanks - Jim

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I'll have to check the FAA manual but I think I remember reading that over sized and elongated holes are a no-no.

For rivets I am quite sure you are right.  But if you think of hole being drilled at ten degree angle, I am pretty sure that is OK.  Especially for bolts as large as the engine mounts.  My flying 601 has over 700 hours and all is well.  I check torque every year.

Well, I got my bolts yesterday and I was surprised but happy I got them to go from inside the fuselage out to the firewall :-). I did temporarily remove one of the an3 bolts from each mount bracket and then just a teeny tiny ream with the drill bit and all is good.

  Thanks for the feedback - you all are the best!

- Jim


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