
Originally Posted by
RC Maple
Sorry, like others on the site, I am having trouble posting a photo. Coming right off the strainer I have a 3-way valve. After that are 3 t's and then an elbow, each with a 5/16 hose barb. The recirculation line coming off the valve has a 3/16 line going into the tank. With the 3-way valve open and no restriction in the line I get 8" Hg. If I close off the valve, the vacuum drops to 6". By putting a c-clamp on the recirc line to restrict the flow, i get my best vacuum which is 10" Hg. I did an experiment today. Moving the vacuum gauge to where the recirc line is and shutting off the rest of the manifold, I still only get <10" vacuum. At what point should I assume the diaphragm?
Also, what should the sap look like in a drop that is below the lateral? Should the line look full of sap? Most of my drops are above the lateral but the one or two that are not look to have sap sitting in them. Would they look this way at 20" too? At some point, does this sap get drawn up into the line?
Sorry for the questions. My hope was that once tapped and the pump running, I would be seeing vacuum numbers like others post about (20" or better). The good news is there is sap going in the tank. As a first timer though, without having seen a working set-up of anyone else's, I am trying to understand the flaws and make it work the best I can.
Are you sure your gauge is accurate? Got another one to try?
I, and others, control recirculation with a needle valve. It doesn't take much so maybe there needs to be a bit more precision in your flow rate there. Hard to say without seeing it in action though.
42.82N
2015 - Small operation. 25 buckets. One excited 5 year old and one 35 year old that feels 5 again.
2016 - One year older. New Homemade 2x4 Arch, Smoky Lake Pan and looking at 52 maples, 17 box elders and 2 walnut trees.
2017 - Shurflo 4008 hooked to 42 stingy silver maples and a few Norways. A couple buckets on sugars and Norways. 10 box elders.
2018 - ...a few more taps.
2019 - ...more taps on 3/16 gravity. This spiral is heading downward in a hurry.
2020 - 4x400 RO - RB20 (uh-oh!)