Owner`s manual

13 14
Installed Cummins Onan Generators Are
Exceptionally Quiet.
Noise Comparison Chart
(in decibels*)
Suburban
living room
Private
office
Normal
speech
Inside a car
at 50 m.p.h.
or inside a
busy office
Rotary mower
Heavy city traffic
Chain saw
Auto horn at 3 feet or
rock & roll bar
Jet plane at 50 feet
Siren at 100 feet
Threshold of pain
quiet
*readings at 10 ft (3 m) at half load
QG 2800/4000RM 70/71 dBa
QG 2800 70 dBa
QG 4000 68 dBa
QD 10000/12500 68 dBa
QD 3200/5000 68 dBa
QG 5500/7000 67 dBa
QD 6000/8000 66 dBa
QG 5500/7000EFI 64 dBa
Preventing Surging
The electrical supply (voltage and frequency) for any appliance must remain within
very close limits for it to operate properly. Changes in the electrical supply (called
surging) can damage the appliances in your RV. Proper care of your generator will
enable it to supply a stable power source and prevent surging.
RV generator engine speed is controlled with a governing system. Most generators
have a mechanical governor, although the latest Cummins Onan EFI generators
and Quiet Diesel generators use an electronic governor. Without a governor, engine
speed simply drops as appliances are turned on, until the generator fi nally stops
running. With a governor, the carburetor throttle opens or the EFI system adjusts to
compensate for the increased load and thus maintains a constant speed.
The governor works in careful balance with the generator engine, fuel system,
regulator and generator. If the balance is upset, surging may result.
A variety of things can cause surging, including an inadequate fuel supply, lack of
exercise and poor maintenance. (See the Troubleshooting Guide on page 29.)
Tips To Help Prevent Surging
Ensure adequate generator fuel supply. Fuel is drawn from a remote fuel tank,
which in many cases is usually the vehicle’s main fuel tank. Typically the generator’s
fuel pickup only extends 3/4 of the way to the bottom of the tank — to prevent you
from completely draining the tank and fi nding yourself stranded at your campsite! In
other words: fuel in the tank does not guarantee fuel to your generator, especially
if you have two fuel tanks in your vehicle. A cracked, leaking fuel line or a defective
fuel pump can also cause inadequate fuel supply to the generator. Contact your
local Cummins Onan Authorized RV Service and Parts Dealer to diagnose fuel
supply problems.
Follow the generator exercise recommendations or the out-of-service protection
recommendations outlined in your Operator’s Manual. Gum and varnish from stale
fuel can plug small carburetor passages causing a lean fuel mixture and surging.
Treat the fuel system with Green Label Parts Premium Fuel System Cleaner in the
clean-up mode ratios. Contact your local Cummins Onan RV Service and Parts
Dealer to have the carburetor cleaned and adjusted or replaced if the problem
persists.
Adjustment should be done on gasoline or LP model’s carburetor, choke, and
governor by your local Cummins Onan Authorized RV Service and Parts Dealer,
who has specialized instruments made specifi cally for this job.
Make sure ignition system components are in good condition.
On carbureted models with a manual pre-heater control lever, set the carburetor air
pre-heater in the proper position for the temperature and humidity at your location.
For temperatures below 55° F and/or high humidity, set the selector in the winter
position.
CAUTION:
When operating electronic appliances (TVs, computers, VCRs, etc.)
in your RV, it is important to use surge protectors to prevent power surges from
damaging your equipment. Cummins Onan is not responsible for damage to sensi-
tive electronic equipment.