HWH Jack problems

[Don Bradner]

During our recent cross-country trip we had problems with our jack motor or pump
that at this point is not precisely diagnosed, and I'm hoping someone has
experienced similar issues.

When the motor is first started, either in automatic mode, or by manually
extending a jack, it runs slow and appears to be laboring. It also osciallates
somewhat in speed. It is drawing 60-70 amps at that point.

Generally, after it has run awhile, it will "kick-in" to high speed, drawing
about 80 amps and will run fine to completion. Not uncommonly, but not always,
it will do that after it has stopped and restarted, either manually, or because
the low jack has completed and it is running the remainder down. Sometimes the
speed never increases, and in those cases the run-time will usually expire
before the jacks are all extended, and another run will be required.

Coincidentally, this behavior started the day after we passed through Moscow, IA


While over Randy's pit in Florida we ran the jacks several times while he
checked for loose ground or hot wire, and nothing was detected. He tried calling
HWH support, but did not get a callback.

Fluid levels are fine; I had checked, and Randy re-checked.

Towards the end of our trip the problem got worse. The new symptom was that the
relays would kick, but the motor would not start. Repeated clicking of a manual
lever would eventually result in the motor starting. It did this for three
consecutive uses, then for the last two including when we arrived home it did
operate on first switching. When the relays kicked and the motor failed to
start, power draw was under 20 amps, around what would be expected for solenoids
and valves - the motor was not apparently drawing any current.

What are your thoughts?

Don Bradner
90 PT40 "Blue Thunder"
Home in Eureka, CA
My location: http://www.bbirdmaps.com/user2.cfm?user=1