A recurring source of irritation for me is these Momentary On Cole Hersee push buttons, which go for $20 on the shelf at West Marine.
They are often the source of surprise engine-won't-start.
I installed new ones, glow plug and start, on my cockpit engine controls six months ago, and just replaced both again. They were frequently under salt water this summer, despite a spray shield over the cockpit panel.
On one button, the right-angle screw tab corroded right off. This was not caused by any mechanical pull, since the back of the instruments is protected by a heavy cover, and the wire is just a short jumper.
The design of these robust-looking buttons is really not so hot.
After smashing one with a hammer, for an "exploded view", the mechanism is apparent. The issue with a stuck button is within the case. Pushing the button presses down a horizontal bar, against two springs, thus making the momentary circuit.
However, there's not much room inside the case, and if the button sticks or won't move it;s because corrosion has gummed up that part of the works. Difficult to get lubricant in there, difficult to wash salt crystals out. Impossible, while the button is installed in the panel.
The buttons can be brought back to life by soaking in fresh water and continued operation of the unit against its springs. It took me about 10 full minutes to get all the glop out.
If the buttons stick, or won't push in, there is not much you can do except putting them through that treatment.
The fellow with the next slip to me sympathized and showed me the two spares he keeps on board.
Stuck buttons always occur as you arrive at the boat with five guests, he said. A point well taken, seems to me.
They are often the source of surprise engine-won't-start.
I installed new ones, glow plug and start, on my cockpit engine controls six months ago, and just replaced both again. They were frequently under salt water this summer, despite a spray shield over the cockpit panel.
On one button, the right-angle screw tab corroded right off. This was not caused by any mechanical pull, since the back of the instruments is protected by a heavy cover, and the wire is just a short jumper.
The design of these robust-looking buttons is really not so hot.
After smashing one with a hammer, for an "exploded view", the mechanism is apparent. The issue with a stuck button is within the case. Pushing the button presses down a horizontal bar, against two springs, thus making the momentary circuit.
However, there's not much room inside the case, and if the button sticks or won't move it;s because corrosion has gummed up that part of the works. Difficult to get lubricant in there, difficult to wash salt crystals out. Impossible, while the button is installed in the panel.
The buttons can be brought back to life by soaking in fresh water and continued operation of the unit against its springs. It took me about 10 full minutes to get all the glop out.
If the buttons stick, or won't push in, there is not much you can do except putting them through that treatment.
The fellow with the next slip to me sympathized and showed me the two spares he keeps on board.
Stuck buttons always occur as you arrive at the boat with five guests, he said. A point well taken, seems to me.
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