Many of today’s low pressure inflatable kayaks use Boston Valves on their bladders. Boston valves are very easy to use. Inflation valves are the “connections” on the kayak that allow air to be pumped into the kayak. The valve adaptor is the fitting that couples the pump hose to the inflation valve.
Boston valves have three components – 1) A base retaining ring (valve collar) that screws onto the kayak bladder receptacle/opening, 2) the valve body and 3) the valve cap. The base retaining ring serves the purpose of also keeping the fabric outer shell opening in position – if you did not have this, the bladder would fall inside the cover, making it difficult to access.
Most kayaks arrive with the retaining ring already screwed onto the bladder receptable – double check that it is screwed on tightly before inflating. If it is not already in position, screw on the ring (collar) making sure that the kayak cover (blue material above) is not scrunched up around the threaded area – this can cause leaks.
Next, screw on the valve body onto the retaining ring – make sure it is not cross-threaded, and it is tightly in place.
Once the body is in place, the kayak can be inflated.
The Boston Valve adaptor is a slightly conical nozzle found on most standard pumps (on right in picture above).
The adaptor couples to the end of the pump hose, and “friction fits” into the Boston valve body. As you start pumping, air is pushed into the bladder.
A flap inside the valve opens when air is pumped into the kayak, and falls shut when not pumped so that air will not rush back out. Please note that if using a gauge, pressure gauges read off back pressure. Thus, the needle will go up as you make the stroke, and fall back to zero when you aren’t. Just keep track of how high the needle goes.
Occasionally, the valve adaptors may be too loose, and will pop out. This can be rectified in a few ways. 1) Put some masking tape or duct tape around the adaptor, to make it a little thicker. 2) Use a rock or sandpaper to slightly rough up the outer surface of the adaptor, or 3) as the Boston valve is “tapering”, slightly cut down the length – this in effect will make the adaptor a bit wider, to friction fit better.
Once finished pumping, screw the cap onto the Boston valve body. You’re done!
To deflate the chamber, unscrew the base connector and all the air will swoosh out. Once the air is totally out, screw the cap back on so the valve doesn’t get misplaced.
Troubleshooting your Boston Valves:
If you believe you have a leak at the valve location, run a soapy sponge around the valve to pinpoint the leak – bubbles will be visible.
First, remove the valve entirely and then carefully re-thread it onto the kayak. Sometimes, the valve can be cross-threaded, or occasionally kayak material can interfere with a tight seal. If that doesn’t work, try swapping the valves. If the opposite side then has a problem, you know it is the Boston valve. Many inflatables come with an extra Boston valve in the repair kit, so replace the culprit. If the same side has a problem, you probably have a leak in the bladder. It neither side goes down, then you probably had it cross-threaded.
Check out this nifty video put together by Tsunami Marketing, on using a Boston Valve.