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   This story is an emotional preface to a more serious technical article. Many months passed, and yet I still recall the following chapter of my hydraulic life almost every day...

   I was "remodeling" hydraulics of  Marine Travelift 70 BFM - a ninety ton (rather small by marine standards) self propelled boat hoisting machine, which for seven years of everyday "boat delivery" had been punished by the Azorean sea and unpredictable weather, with the preventive maintenance boiled down to topping up the hydraulic oil and diesel when needed, along with hydraulic hose replacement program based on the "not burst - still good" principle. In the end of the seven years the machine "got tired" (as the fishermen would say) and the hoist operations began to take much more time than usual, jeopardizing normal work of the local fishermen community. The matter demander urgent attention, because the whole village literally depended on fishing for survival.

    The machine was 100% hydraulics driven. Countless oil lines ran along the twelve meter high frame, with dozens of oil hoses in every corner, all completely rusted and deteriorated by the salt water. The circuit itself wasn't that complicated, but boy was it extensive! As you can imagine, most of the hydraulic components were damaged beyond repair, especially the manual ten section distributor valve, which was leaking oil from everywhere as the spools were completely consumed by corrosion.

   We did manage to get a price for the exact replacement, but the terms of delivery were unacceptable, and therefore our only chance was to "make it work" with "what we had". The fastest solution was replacing the manual distributor with four PVG-32 Sauer Danfoss valves with electric controls, and the obsolete and extensively rusted manual levers with a nicely looking panel carrying modern joysticks and buttons. I still do prefer using good old hydraulic pilots for harsh environments, but the lack of time was a serious issue, and electric installation was the fastest solution, plus electrically controlled valves would allow for future "luxury" add-ons, like remote wireless control option, for example, which is a nice "extra" to have on a machine like that.

   The machine also got a new five section pump, a new and bigger oil tank, new winch motors, new hoses, new power steering, new and better filtration, new oil cooler - everything. The mechanical part - the sheaves, wire ropes, the diesel engine  - was also overhauled and repaired. Due to the extreme urgency factor of the intervention, the aesthetical side might have suffered a little, meaning that a "faster but  functional" solution was always chosen over the "more aesthetic" one. 

   The crew had to work in unbelievably difficult conditions, and the fact that the machine was situated in a relatively remote region made the work even harder. The deadline was coming close and sixteen and eighteen hour work days became our routine, but through an enormous effort the hydraulic part was mounted with only a minor delay, and the build entered the next phase - hydraulic system testing and adjustment.

    Like I mentioned above - the whole village depended on the machine for survival (and believe me, I am not exaggerating here) - so about every hour a fisherman would come around to ask when the Travelift would be ready. The reason for that was very simple - there was no other alternative way of getting the small fishing boats in and and out of the water, and the  harbor couldn't protect the small boats from bad seas, so all the boats had to come ashore in bad weather, and go back into the water when the weather improved. Then, of course, there were about a hundred of other reasons (I could never possibly understand) for the boats to be constantly hoisted in and out of the water. The intervention period was carefully chosen during the good weather stretch and all the village had been notified in advance, but still every day there was a boat owner who wondered if we could, well, just for that once and as a personal favor to him, close our eyes and let him use the rig "for a couple of minutes"...

   No words can describe the "audience" that gathered around the machine as the first "real boat" test was about to begin.... Literally hundreds of fishermen were curiously watching every step of "him hydraulic fellow" (yours truly) working his magic . The word in the village was - a "foreign engineer from far abroad" was summoned to repair the Travelift. Believe me, being that kind of a center of attention is all but comfortable.

   As the machine had been run the night before (I recon that night we went to sleep at around three a.m.), I was pretty confident that the real boat test was just the matter of  checking the pressures... The first small boat was lowered into the water smooth and fast - the crowd was roaring in approval because the folks had gotten used to the very low hoisting speeds and naturally were amazed by the agility of the reborn piece of machinery. The machine made another trip to pick up a recently built boat that hadn't yet been in the  water. As the vessel was being winched down, I was unpleasantly surprised by the massive five section hydraulic gear pump, that  suddenly started to "spit out" jets of oil from between the sections, along with extruded  o'ring remains. The boat was half way down and already too low to move the machine, the attempt to lift it back up was unsuccessful - the poor pump would stream the oil out and the pressure wouldn't rise enough to lift the heavy boat. A decision was made to lower the boat, winch up the cables, take the machine to the repair spot, and see what can be done. However, to my great horror, as soon as the boat was lowered (remember that it was a new boat that'd never been in the water), it started TAKING IN WATER!!!  At that moment the thought "I am so f'cked!" was one of the most decent thoughts that ran through my head...

    The next ten minutes I spent in hell, explaining to the fishermen that the machine was physically incapable of hoisting the boat back up due to the malfunctioning pump, and that the pump was the ONLY pump of that kind on the island... Thank God the men managed to repair the water leak, and I was able to sigh in relief. The crippled and bleeding machine slowly crept to the "ground zero" next to our portable workshop, leaving a sad looking oil trail behind...

   The aftermath - a person from Lisbon caught the first flight to the island and brought over a repair kit. The pump was repaired that very night and the machine was put back in service good as new. I can't remember exactly, but I think we slept for about five hours during these two days...

    This (I am not afraid of this word) heroic story, besides the "almost sunk boat" coincidental predicament, brought up a couple of interesting hydraulic phenomenae behind the split multi-section gear pump malfunction, which are discussed here.

    In any case, this story is another good proof that hydraulic technicians live a truly filled life...