Anyone get air and no sap from tree spout? (Vacuum Leak)

[DoubleBrookMaple]

Today I struggled for a long time with a bad vacuum leak that was dropping my vacuum from 24.5 to 22.5...

I could hear it at the saddle, and walked the lateral and checked all the spouts visually, and listened, but no leaks apparent. I worked on the saddle again, and again. Finally I kinked the lateral to isolate it, and the noise stopped. OK... It is in the lateral line! I did a detailed visual, and finally found air bubbles in a drop tee fitting. It was air coming down the drop. I cut off the spout line and capped it. Leak (bubbles stopped). I changed the spout, not help. NO SAP from spout. I could hear nothing! I cut off the spout, capped the line and walked away.

I believe it was sucking a LOT of air from the tree... I could see no bubbles at spout, because no fluid, or so much air anyway.

What do Y'all think?

[Mini_Maple_Men]

Had the same problem on my 3/16 line! The only fix I found was the same as you, plug it and walk away. Tried net tap and drop but neither worked. Lee

[lpakiz]

Good bet it was a hollow tree, or you were in a crack or seam, either natural or frost or tapper induced.
If your really curious, drill another hole several inches away and see what you get then. If the tree is hollow, I can make it work by drilling in at a tangent, I mean, not perfectly straight in. Just so the inside end of the hole doesn't get too close to the hollow spot inside.

[Russell Lampron]

Hollow tree! I have found 4 of them this season. The tree is junk now anyway so drill another tap hole kind of sideways and not too deep and try again.

[WestfordSugarworks]

Kinking the lateral is what I do also. We've had quite a bit of trees like that. Sometimes we have success drilling a second hole, sometimes the tree doesn't have any good tapping wood left on it and we take the drop right off. I've found that especially small red maples are prone to leaking. Rarely do I have a problem with a 16 inch sugar maple. It sounds like you did the right thing, maybe keep an eye on that tree next year if you decide to tap it again. If it was leaking that bad this year, I bet you'll have a hard time finding good tapping wood in it next year but who knows. Was your saddle iced up at all? Today I found 3 or 4 saddles that either were leaking at the saddle or the lateral had a squirrel chew or there was a bad tap or something. The exterior of the saddles was covered in snow and ice and the mainline was frozen solid. Pretty cool to see that and a good feeling to fix the problem, raising the vacuum and allowing better production at all the taps higher up the mainline.

[Wanabe1972]

I had this happen last year on a tap hole and found the vacuum leak was coming from the previous years tap hole 4 inches away. Your tree may be hollow.