Axles And Bearings; Battery; Battery Amp Draw And Testing - Airstream (nest) 2019 Owner's Manual

Axles and Bearings

• Torsion Axle Alignment Specifications
Toe-In and Camber Specifications
Toe-In each side 1/16 in.
Camber each side 3/4°
NOTE
Never allow heat to be applied to the axle tube
because the rubber providing the spring torsion
action will be severely damaged.
• Wheel Bearing Maintenance
1. Jack trailer at marked jack location pad behind axle on
mainframe,
2. Remove hubcap or spindle cover, wheel and tire.
3. Remove dust cap.
4. Remove cotter pin.
5. Remove spindle nut and washer.
6. Remove bearings and hub.
7. Lay down hub with inside grease seal down. Knock
out inner bearing and grease seal using wood or
plastic dowel and hammer.
8. Clean all parts thoroughly with kerosene.
9. Check all bearings and races for chips or roughness of
any kind. Any damaged component must be replaced.
10. Pack bearing with a good grease (No. 2 Grade-265
ASTM penetration or equivalent).
11. Install inner bearing.
12. Install new grease seal in hub or rotor using wooden or
rawhide mallet.
13. Install hub and drum on spindle.
14. Install outer bearing.
15. Install washer and spindle nut.
16. While rotating the wheel, tighten the spindle nut with a
12" torque wrench until there is a slight tension. Then
back off one notch and install cotter pin. There should
now be from .001" to .010" end play in hub. If not,
back off one notch.
17. Check the lug nuts for tightness at 10, 25 and 50
miles of travel. See Specification Section in this
manual for wheel torque ratings.
NOTE
The wheel/hub assembly on a new axle will take
some time and miles to settle into its proper and
centered position within the wheel well. New
trailers are designed with this eventuality built-in,
so wheels will initially appear to be off-center.
Tolerance 1/8 in. + or —
Tolerance 3/4° + or —
(degrees) positive
Batteries
Your Nest trailer is factory equipped with
two 95 amp-hour Interstate® SRM-24
Deep Cycle lead-acid batteries.

Battery Amp Draw and Testing

All batteries will have an Amp Hour (AH) rating. The AH rating on
a battery is its "C/20" rate or 20 hour discharge rate. As long as
a battery is discharged over a 20 hour, or longer period, it will
deliver 100% of its rated capacity. If it is discharged in less time
at higher currents it will deliver less capacity.
To further help define "amp-hours," here's an example: a battery
with a 100 amp-hour capacity can deliver one amp for 100 hours
or it can deliver 100 amps for one hour. Batteries are able to
deliver current longer if they are discharged at a lower rate and
deliver less current at a higher discharge rate.
For proper load testing the battery needs to be fully charged and
the voltage should be greater than 12.8volts. A typical load test
should be 3 times the amp hour for 15 seconds. At the end of 15
seconds the voltage of the battery should stay above 9.6 volts.
If the battery cannot reach a fully charged voltage of 12.8 or
greater the batteries will need to be equalized.
NOTE
When checking the state of charge the battery
needs to have been disconnected from a charging
source and any loads for a minimum of four hours.
WARNING
Before removing the batteries verify that shore
power is not connected. Risk of electrical shock
may be present.
The following chart shows the approximate % of charge SOC
(State of charge) vs. OCV (Open circuit voltage) and specific
gravity for Interstate batteries.
SOC
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
OCV Specific Gravity
12.84 1.300
12.73 1.282
12.65 1.268
12.57 1.255
12.49 1.242
12.41 1.228
12.33 1.215
12.25 1.202
12.17 1.188
12.09 1.175
12.01 1.162
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