Dear subscribers,

Hydraulic 4P:

When I move my flaps down at about 70% of the travel my pump comes on for approx 0.5 to 1 sec. The flaps then retract without the pump coming on. When I move them down again at 70 % travel the pump comes on again. (the pump is continuously on when it starts up – it does not come on and off in very short intervals)

When I pull the circuit breaker I get almost 3 complete flap cycles out of the accumulator.

I tried to bleed out the air from the system at the fittings of the flap cylinder, the accumulator and the bulk head where it goes under the rear seat. I do not get any air – just oil.

When I filled my hydraulic system the first time I did not have this problem – I got approx 1.5 flap cycles before the pump kicked in.

I changed two things in the mean time:

1. I increased the flap cylinder stroke by approx 5 mm (1/4 “) by adjusting the hard stop.

2. I removed and put back in all hydraulic lines that run from the front to the rear of the cabin on the floor (I found a significant cabin pressure leak in the tunnel for the hydraulic lines under the front seats that needed to the fixed)

The function of flaps and gear works fine. Is the described situation acceptable or do I have to worry about air in my system that needs to come out (and how to get it out if so)

Thanks for your help

Ralf