Folks,
I finally tested gear retraction on my 1990 320 FB. Here's a symptom
that may or may not be normal.
- Gear Switch in down position. Master Switch off. Dump valve
open.
- Close the dump valve.
- Master switch on. Pump runs for a few seconds, pressuring the low
pressure side.
- Gear switch to up position. Pump runs intermittently, raising the
gear in fits and starts. Eventually gear is up and doors are
closed. Pump stops and remains off—so no evidence of pressure
loss.
- Master switch off. Leave gear switch in up position. Gear
stays up.
- Open dump valve and gear comes down smoothly and locks.
- Close dump valve.
- Master switch on, and gear comes up continuously and steadily.
- Gear switch to down, and gear comes down steadily.
I’m guessing the intermittent operation in 4 results from the pump
competing with back pressure from the low pressure side.
Is intermittent retraction normal without the benefit of the alternator
charging for this variant of pump? Do we know if it is LL, LB, LD, or some
other?
The battery is a fully charged Odyssey PC680. The voltage with the
pump operating smoothly (see 8 and 9 above) is 11.3 Volts at 41 Amps retracting
and 31 Amps lowering.
I have ordered pressure gauges for the high and low circuits. What
pressure should I look for on the low side while retracting? How much is
too much?
Thanks in advance for ideas.
Regards, Chris.