Holiday imperial 2001, Owner'S Manual, Page: 280 / 301

Chassis Information
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
I M P E R I A L
1 0 • 2 8 0
The correct adjustment technique, with a full tank of fuel, is to start with the
full adjustment screw completely clockwise. This should cause the reading to
be above full. Adjust slowly counterclockwise until the full mark is reached.The
intent is to always adjust downscale rather than upscale.
Troubleshooting:
A. Electronic output. The sender has a transistorized output. This prevents
an ohmmeter from getting a correct reading of its output resistance.
B. Fuel Only: The sender will not work correctly in conducting fluids such
as water (it will read above full all the time in water). One possibility,
when you have a constant above-full reading, is that you have water at
the bottom of the fuel tank.
C. Contact Centroid: Probably 90% of the returns Centroid tests work okay
on the bench. If you have incorrect readings contact Centroid (tele-
phone: 800-423-3574, or preferable fax: 904-423-3709) with your
symptoms. You will be provided with a short “fill in the blanks” trou-
bleshooting test appropriate to your sender. It is easier to find the prob-
lem that way than after the sender has been removed from the system,
since the problem is not necessarily with the sender.
The motorhome uses a engine driven hydraulic pump to operate both the
power steering system and the engine hydraulic cooling fan system. The dual
stage hydraulic pump uses one half of the pump to supply pressurized hydraulic
fluid to the power steering gear assembly. The other half of the pump supplies
pressurized hydraulic fluid to the engine cooling fan motors. The hydraulic
system uses the same fluid for both systems sharing one common reservoir.
The hydraulic fluid used is an automatic transmission fluid (Dexron3) which
has a wide ambient temperature operating range.
CAUTION: If ambient temperatures approach 0º Fahrenheit,
Pennzoil Arctic Blue hydraulic fluid or equivalent hydraulic fluid
should be used. Using incorrect hydraulic system fluid weights in
cold or arctic temperatures will raise the hydraulic system operat-
ing pressure and may damage the hydraulic cooler.
The hydraulic pump creates pressure by meshing sets of gears together
inside a close tolerance housing. A filtered supply of hydraulic fluid from the
hydraulic reservoir enters the intake side of the pump. The meshing gear assem-
bly “squeezes” the oil through the pump to the output side delivering the pres-
surized fluid to the power steering gear and the switching valve of the engine
cooling system. Each half of the pump is equipped with an internal bypass pres-
sure relief spring. If the hydraulic pressure should exceed the specified pressure
limit, the internal by-pass relief valve will be forced open to keep the hydraulic
fluid at operating pressure. The hydraulic pressure generally is not rated in psi
but is rated in the term bar. One bar is equivalent to approximately 14.5 psi.
Hydraulic system pressures with a system at no load may be as low as eight bar
Hydraulic Pump
HYDRAULIC
SYSTEMS (ISC)