I have never worked with fuel tank fittings before so this may sound like a dumb question. I'm building an RV-8. The fuel pickup tube fitting is supposed to have an anti rotation bracket, but the plans do not indicate one for the vent line. I read somewhere that rotation is not as much of a concern when the fixed nut part of the fitting is outside of the tank (as it is on the vent line fitting) because you can hold it in place with a second wrench when tightening down the line. Even if that's true, would it be safer to have an anti rotation bracket on the vent line fitting just in case so the seal doesn't get broken at some point?
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Anti rotation bracket on vent line fitting
- Thread starter Ben Ellis
- Start date
I see the later RV14 & 10 kits use an anti-rotation plate on their vent fittings, part# T-1010.
The vent line on my RV6 is a 90* bulkhead elbow with the 90* elbow end being on the outside of the tank. That means the nut is on the inside. The fitting is installed with generous amounts of proseal both in the opening and completely covering the tightened nut on the inside. I think there is a large area washer on the outside to reinforce the opening and also gets plenty of proseal. It couldn’t turn if you wanted it to.
On the RVs that have a 90° fitting on the tank for attachment of the external vent line, when you are tightening the line you were not inducing a rotation on the fitting installed in the tank, so no anti-rotation component is needed
When the vent is connecting to a straight fitting on the tank, tightening, the external line is inducing a rotation on the fitting, and then an anti-rotation component is utilized
When the vent is connecting to a straight fitting on the tank, tightening, the external line is inducing a rotation on the fitting, and then an anti-rotation component is utilized
We are building a -10. It uses the straight bulkhead union AN832-4D with a T-1010 anti-rotation bracket.
Is there a reason to avoid installing (sealing) the bulkhead union at the same time as the T-1010 anti-rotation bracket is riveted? It seems they should be done together since the filet of sealant from the cutout in T-1010 could interfere with the AN832-3D. Scott (in post 3 above) recommends
Thoughts?
Cheers!
Mike
Is there a reason to avoid installing (sealing) the bulkhead union at the same time as the T-1010 anti-rotation bracket is riveted? It seems they should be done together since the filet of sealant from the cutout in T-1010 could interfere with the AN832-3D. Scott (in post 3 above) recommends
Thoughts?
Cheers!
Mike
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There’s no reason they can’t be done at the same time, but there’s no reason they couldn’t be done at different times either, as long as all sealant squeeze out was removed from the hex shaped area inside the bracket so that the fitting can nest properly when it is installed.
