Onan NHC User Manual

With oil in crankcase, start engine and check for leaks
around filter element. Retighten only as much as
necessary to eliminate leaks, but do not overtighten.
IGNITION
Spark Plugs
Check, and regap spark plugs every 100 hours of
operation (Figure 3). Replace spark plugs that show
signs of fouling or electrode erosion.
FIGURE 3. SPARK PLUG GAP
Cleaning Batteries
Keep the batteries clean by wiping them with a damp
cloth whenever dirt appears excessive.
If corrosion is present around the terminal connec¬
tions, remove battery cables and wash the terminals
with an ammonia solution or a solution consisting of
1/4 pound of baking soda added to 1 quart of water.
Be sure the vent plugs are tight to prevent cleaning
solution from entering the cells.
After cleaning, flush the outside of the battery, the
battery compartment, and surrounding areas with
clear water.
Keep the battery terminals clean and tight. After
making connections, coat the terminals with a light
application of petroleum jelly or non-conductive
grease to retard corrosion.
Checking Specific Gravity
Use a battery hydrometer to check the specific
gravity of the electrolyte in each battery cell.
Hold the hydrometer vertical and take the reading.
Correct the reading by adding four gravity points
(0.004) for every five degrees the electrolyte tempera-
ture is above 80° F (27° C) or subtracting four gravity
points for every five degrees below 80°F (27°C). A
fully charged battery will have a corrected specific
gravity of 1.260. Charge the battery if the reading is
below 1.215.
Breaker Points
Check breaker points every 100 hours. Replace
points and condenser every 200 operating hours.
Replace sooner if points are pitted or burned. See
ADJUSTMENTS section.
COOLING SYSTEM
Check and clean cooling fins and chaff screen at least
every 50 hours. Remove any dust, dirt or oil which
may have accumulated.
BATTERIES
Disconnect negative ground strap from the battery
before working on any part of the electrical system or
engine.
Disconnect positive terminals before charging batter¬
ies to avoid damaging alternator or regulator.
AWARNING
Ignition of explosive battery gases
can cause severe personal injury.
Do not smoke while servicing batteries.
Checking Electrolyte Level
Check the level of the electrolyte (acid and water
solution) in the batteries at least every 50 hours of
operation.
Fill the battery cells to the bottom of the filler neck. If
cells are low on water, add distilled water and
recharge. If one cell is low, check case for leaks. Keep
the battery case clean and dry. An accumulation of
moisture will lead to a more rapid discharge and
battery failure.
ACAUTION
Do not add water in freezing weather
unless the engine is to be run long
enough (two or three hours) to assure a thorough
mixing of water and electrolyte.
Storing Batteries
If the engine is to be stored for more than 30 days,
remove the batteries. With the electrolyte level at the
bottom of the split ring, charge the battery before
storing it. After every 30 days the battery is in storage,
bring it back up to full charge. To reduce self¬
discharge, store the battery in as cool a place as
possible so long as the electrolyte does not freeze.
7

Onan NHC Specifications

General

Brand	Onan
Model	NHC
Category	Engine
Language	English