PART II
MI35.1505
11JAN96
LOCATING THE JACKS
mounting bracket for the flanges of the frame rail, is important.
widest possibe pattern. Always bolt at the top and bottom of the
frame rail whether using mounting brackets, or bolting straight
acting jacks directly to the frame rail.
HWH Corporation does not suggest welding brackets or
straight acting jacks to the frame rails. Do NOT weld kick down
jacks to the mounting brackets or directly to the frame rail.
(See Section B-WELDING) If it is necessary to modify the tail-
will reduce stress in the vehicle and leveling system. When a
tag axle is used the jacks should be mounted between the drive
axle and the tag axle. Mounting the front jacks in front of the
ation or the coach manufacturer before mounting the front jacks
in front of the front axle.
up towards the rear of the vehicle when retracted. Mounting
gested. Mounting jacks that will fold toward the front as in FIG-
URE 3 is unacceptable.
3. JACK MOUNTING HEIGHT:
ing heights or locations refer to the Clearance and Mounting
Dimensions Charts. Combining these dimensions and in-
formation supplied on the "JACK BRACKET" sheets (See
"BRACKETS"-HWH Service Manual) will make it possible to
figure proper mounting heights and locations before starting
the installation. In most cases these mounting heights will
provide clearance on uneven terrain and permit the placement
of a pad under the jacks when operating on soft ground or
asphalt. (Pads are available from HWH Corporation)
shown on the Dimension Charts apply to vehicles with a full
load of fuel, water and equipment. When empty add 1" to
these dimensions. Also take into consideration that new ve-
hicles can settle down 3/4" or more during the first year or
initial 10,000 miles.
suggests using straight acting jacks on vehicles with full air
bag suspension. The vehicle should be at the proper ride
height when determining the proper mounting heights for
the jacks. If kick down style jacks are used, add 2 inches to
the suggested jack mounting heights.
CAUTION:
VEHICLE WILL RAPIDLY DROP SEV-
ERAL INCHES IF AIR BAGS DEFLATE.
DEFLATE AIR BAGS BEFORE WORK-
ING UNDER THE VEHICLE.
4. DEFLATING AIR BAGS:
the vehicle’s frame must be securely blocked. The air can
be released by disconnecting the air line between the height
control valve and the air bag. Usually the fitting at the height
control valve is easiest to get to. (See the SUSPENSION AIR
DUMP DIAGRAM)
IMPORTANT:
quickly. Make sure there is adequate clearance to work under
the coach.
SWING TO REAR
IDEAL
FIGURE 1
FIGURE 2
SWING TO REAR
NOT SUGGESTED
FIGURE 3
SWING FORWARD
UNACCEPTABLE
FIGURE 4
SWING SIDEWAYS
NOT SUGGESTED
2. MOUNTING ARRANGEMENT:
tion for the jacks is important for the proper functioning of the
When the air is released the bags will deflate
pipe, have the owner take the vehicle to a professional muffler
shop for proper procedure before starting installation.
Most brackets are designed with specific bolt hole arrangements.
Use of all holes, especially holes used for the fingers of the
possible behind the front and rear axles. (See FIGURE 1) This
axle is not suggested. (See FIGURE 2) Contact HWH Corpor-
Vehicles with spring suspension: The ground clearance
Vehicles with full air bag suspensions:
JACK INSTALLATION
1. MOUNTING BRACKETS: HWH Corporation has bolt-on
mounting brackets available for many different applications.
(See "BRACKETS"-HWH Service Manual) Most of the brack-
ets are designed to fit a specific chassis in a specific location.
Slight modification of these brackets is acceptable but HWH
Corporation should be contacted when modifying or changing
the mounting locations of these brackets. The kick down brack-
ets are designed for use with 6000# and 9000# jacks. Many
vehicles requiring 16000# jacks are equipped with mounting
brackets for these jacks. Contact HWH Corporation for mount-
The correct mounting loca-
When figuring proper mount-
Before deflating the air bags
When using brackets with multiple sets of bolt holes, use the
the jacks in other positions as shown in FIGURE 4 is not sug-
ing information when needed.
HWH Corporation
leveling system. The jacks should be mounted as close as
Kick down style jacks must be mounted so that they swing
