[VAC] Re: water pump question

[jon fitz <fitzjo1@xxxxxxxxx>]

If I understand the question rightly, the concern is
that there is a noticeable pulsing of the 12VDC supply
while the pump is running.  Presumably this provides a
lighting effect that is well-suited to a disco, but
little else.  If I'm wrong, please ignore the rest of
this message.

The amount of current drawn by the pump motor will
increase as a result of higher resistance or lower
speed (generally related to resistance, as well).  I
have a rebuilt PAR in my 68.  It draws some juice, but
I haven't noticed much effect on other 12V devices. 
If your unit has an amp gage, you could use it to
quantify the variations.  If the variations are only
perceptible at the amp gage, don't worry.  The pump
cycle is not uniform, so the current draw will vary
during it.  I think the draw is somewhere around 5
amps (been awhile).

I would guess that there is a problem with the pump. 
You could have a pressure switch that is set too high,
is damaged or is blocked.  Or, there could be
mechanical trouble that is causing high friction. 
Both are relatively easy to check and repair.  Put a
pressure gage on the system.  Turn the pump by hand
(after turning the switch off!) to gage resistance. 
Put a little oil on the bearings if in doubt.

Repairs are generally not too expensive on this unit.

Jon in SC 
68 Overlander