A month or two before the sap starts flowing your mind should be cranking through your to-do list to ensure your operation is in tip-top condition. Mid-December is a great time to inspect lines and to make adjustments to your tubing system. The work you do before the season will probably determine how well your system will perform during the season. Here are some things to consider and watch for as you work on your tubing system prior to tapping.
How many times have you said to yourself, this system just does not perform as well as it did when we installed it? You have to realize the first year of maple tubing system’s life will be its best year, simply because it is brand new. The spout and drops are new and everything is tight and working properly. After the first year a system’s performance will depend on how well it is maintained. Leaks will develop and those leaks can expose flaws in the system. Finding and repairing leaks is the first step to achieving high vacuum. The problem with doing work on lines prior to tapping is that you do not have the benefit of finding leaks aided by a running vacuum pump. However, with careful inspection you can spot and repair many potential trouble spots that will cause problems later.
The first step is to walk the woods making sure that all of the lines are up and running tight and straight. Inspect all the tubing that is in contact with tree trunks. These areas are where you will find the vast majority of squirrel chews. If the critters have been chewing, this should be relatively easy to spot. Make sure you not only look for chew holes but also scrapes where the little vermin start to chew and back off for whatever reason. Next you need to look for old connections on tees that have been stretched and twisted, replacing old tees where they are needed. If your system has some age, you might consider replacing all drops and spouts. Research out of the Cornell University maple program found that production can skyrocket 50% just by installing new spouts and drops in an older system. A couple of interesting side notes are that you can come very close to this by keeping the old dropline and installing a new check valve adapter every year. Many producers are finding it more convenient to replace the spout every year and the drops every third year. A helpful tip is to use a different color tubing on new drops so that you can quickly identify the drops that need to be rotated out.
Three areas to check on main lines are the saddles, boosters, and line connectors. Check for old, worn, or stretched saddles. If the loop line going to the saddle has become disconnected and is pulling hard on the saddle itself replace the saddle immediately. Once the seal on the saddle is twisted you will more than likely not be able to properly re-seat the saddle without leakage. Saddle leaks are notoriously difficult to detect and can quickly become the site of major vacuum loss. Another trouble spot are the boosters on a Wet-Dry line. Most of these are made of PVC plastic. PVC plastic was developed for indoor plumbing in buildings. It is not designed to be left in direct sunlight for long periods of time, and the result is degradation of the plastic due to ultraviolet (UV) light from the sun’s rays. The UV Light and exposure to hot and cold will also breakdown the glue in the joints. All PVC fittings should be inspected and replaced on a regular basis. If you use a PVC line from your vacuum pump to your releaser, including your moisture trap, make sure you inspect this area for loose or cracked joints as well. These areas are not only exposed to UV light but experience major vibration that can cause damage to the line over time.
Another location where vacuum leaks can occur is where lines are joined together with Cam Lock couplings. Producers need to replace the rubber gaskets on the inside of these couplers on a regular basis. Also try not to exert a lot of outward force on these connections. The work best when they couple together with little force.
Most of the above locations can be inspected without having to run the vacuum. Of course, the final inspection will need to be made once the taps are in and the vacuum is running, but you will be ahead of the game if most of the obvious and routine checks are complete ahead of time. If you can flush lines with water prior to using them, many leaks will also appear during this process. However, this may not be possible due to weather conditions. Early inspections and maintenance can offset hours of costly repairs and down time once the season starts, and disruptions at that point affect the bottom line – production.
Author: Les Ober, Geauga County OSU Extension 