Yesterday I stuck my hand through a mesh of wires and hoses deep under in Pesto’s bilge and – “Plop” – the generator’s exhaust pipe disconnected from a hose.
It came out too easily. The root cause is that the hose is a bit too short and pulls on the connection. But the enablers were the twin hose clamps which went lose.
Right there and then I got the message – the boat was “talking to me” – and I obliged, instituting the “Hose Clamp Day”.
Hose Clamps are ingenious devices. A screw pulls on a metal strap, which in turn tightens a hose to whatever it is being connected. Made of movable parts, they have the virtue of enabling untightening without sacrificing themselves or the point of application. And therein lies the caveat – like anything movable, they must be inspected periodically.
I don’t know whether hose clamps can untighten in perfectly static situations (I bet not), but as soon as things start to move, they do. Particularly vibrations of the cyclical type – similar to the ones generated by engines – can “stimulate” the screw on the clamp to move the “wrong” direction, starting a slow process of untightening. And, I believe, the less tight the clamp is, the more likely it can be stimulated by the vibration – a vicious cycle.
Most boats have hoses. Some of these hoses contain gases, others connect underwater through-hulls to equipment, and so on. Whatever the case, if a hose clamp loosens in a yacht, chances are something bad may happen.
And the Exhaust Pipe event of yesterday was a blunt reminder that this service was overdue on Pesto. So today I woke up with the firm intent to attack all hose clamps onboard and check for tightness. The “Hose Clamp Day”, which will now have to become part of our maintenance routine here … yey !!!
It took me more than half a day to access and check the ~150 clamps onboard. Here are some relevant facts from it:
- About ½ of them are “reasonably accessible”, the other half requiring contortionism, some 10 being ridiculously difficult to reach, and one being virtually impossible (I will have to pray for this one, and check it weekly – luckily it feels tight to the blind touch, and regular checking is something that can be done with no harm).
- Of the 150, less than 10 were “tight enough”, the rest requiring tightening. Some 20 were quite loose, with 2 being actually completely open, and one broken (ironically, the second hardest one to reach).
- The ones that were less tight were closer to sources of vibration and/or at the worst access places – namely the Engine Room. Not surprising.
- The socket wrench is by far the best tool for it. In a few cases, for lack of access, I needed to use a crescent wrench and just in two clamps was it necessary to use a long flat screwdriver.
I had to crawl into small holes, stick my hands and arms through mazes of hoses, wires and pipes. But all was done elegantly: no lost tools, no broken things, no hurt limbs, no swearing. Now our hoses are all securely connected and, as is the case with every new job I do on Pesto, I got to know our home a little better.
So … got a boat? Got hose clamps? Better check ‘em.
PS – the short exhaust hose that triggered this whole story will be replaced this week