CurlyDave
Elite Member
To me, the reason to never connect implement lines together is that if the temperature increases at all, thermal expansion will cause the hydraulic oil in the implement to try to increase in volume. Since the hydraulic cylinders are essentially constant volume, the only way the oil can expand is to ever so slightly swell the hydraulic hoses. There is a huge increase in pressure and it can become very difficult to unhook the two couplers from each other, requiring much more strength than I can muster.
Similarly, if the lines are not coupled together, the couplers all have a no-leak design, and the hydraulic pressure in the implement increases to the point where no connection to the tractor fittings can be made.
For me, the typical scenario is that I go out in the morning to do some job. I usually have the 4-n-1 bucket on the FEL, and I drop it off to connect something else, like a grapple. Understanding thermal expansion, I leave the 4-n-1 in the shade, or in a spot which will be in the shade when I am done with the grapple. Now, if I have estimated the time of grapple use, or the sun's position incorrectly, when I come back, not only had the day warmed up, but the bucket is in full sunlight and there is too much pressure in the lines to reconnect them. This happens whether the hoses are connected together, or not connected. Now moving the bucket into the shade frequently helps, and I have done this many times.
However, a spare pair of connectors, deliberately set up to not hold hydraulic pressure, placed on the lines when I take the 4-n-1 off, eliminates the need to move the bucket, and means that I can hook it up and start working again with no delay.
Of course, if you have the very expensive connect under pressure type of connectors this is not a problem. Right now, I have 3 FEL implements (4-n-1, grapple, hydraulic auger) and it would be much more costly to retrofit with the hose ends than to use spare connectors I can buy on-line at very reasonable prices.
