water pump GMC SIERRA 1995 Owners Manual

The coolant level
should be a1 or above
the
COLD mark. If it
isn’t, you may have a
leak in the radiator
hoses. heater hoses,
radiator. water
pump
or somewhere else in
the cooling system.
A CAUTION:
Heater and radiator hoses, and other engine parts, can be very
hot. Don’t touch them.
If you do, you can be burned.
Don’t run the engine
if there is a leak. If you run the engine, it
could lose all coolant. That could cause an engine fire, and you
could be burned. Get any leak fixed before you drive the vehicle.
NOTICE:
Engine damage from running your engine without coolant isn’t
covered
by your warranty.
If there seem to be no leak. start the engine again. See if the fan speed
increases when idle speed is doubled
by pushing the accelerator pedal down.
If it doesn’t, your vehicle needs service. Turn off the engine.
How to Add Coolant to the Coolant Recovery Tank
If you haven’t found a problem yet, but the coolant level isn’t at or above
the COLD mark, add
a SO/SO mixture of c.lea12 water (preferably distilled)
and
a proper antifreeze at the coolant recovery tank. (See “Engine Coolant”
in the Index for more information about the proper coolant mix.)
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Cooling System - Diesel Engines
When you decide it‘s safe to lift the hood, here’s what you’ll see:
A. Coolant surge tank pressure cap
B. Engine fan(s)
C. Radiator
A CAUTION:
If your vehicle has air conditioning, the auxiliary electric fan
under the hood can start up even when the engine is not running
and can injure you. Keep hands, clothing and tools away from
any underhood electric fan.
If the coolant inside the coolant surge tank is boiling, don’t do anything else
until it cools down.
The coolant level
should be
at or above
the
COLD mark. If it
isn’t,
you may have a
leak in the radiator
hoses, heater hoses,
radiator, water pump
or somewhere else in
the cooling system.
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Canadian Fuels
Diesel-powered trucks are now equipped with emission control systems that
require the use of diesel fuel with low-sulfur
(.05% by weight) content.
Both low- and higher-sulfur fuels will be available
in Canada. Only
low-sulfur diesel fuels are available
in the United States. It is important that
diesel-powered trucks are refueled with low-sulfur fuel. Use of fuels with
higher-sulfur content will affect
the function of the emission components
and may cause reduced performance, excessive smoke and unpleasant odor.
Cold Weather Operation
Follow the instructions listed previously under the heading “What Fuel to
Use.”
If you’re driving
in very toold temperatures and can’t get a “winterized”
Number
2-D that has been adapted to cold weather or a Number 1-D, you
can
use one gallon of kerosene for every two gallons of diesel fuel. Once
you add the kerosene, run your engine for several minutes
so the fuels will
mix. Add kerosene only when the temperature falls below 0°F (-1 S”C),
because the fuel economy of kerosene isn’t as good as that of diesel fuel.
NOTICE:
Never use home heating oil or gasoline in your diesel engine. \
They can cause engine damage.
In cold weather, your fuel filter may become clogged (waxed). To unclog it,
warm the filter to between
32°F and 50°F (OOC to 10°C). You won’t need
to replace
it.
Water in Fuel
Sometimes, water can be pumped into your fuel tank along with your diesel
fuel. This can happen
if a service station doesn’t regularly inspect and clean
its fuel tanks, or
if it gets contaminated fuel from its suppliers.
If this happens, a WATER
IN FUEL light will come on. If it does, the excess
water must be drained. Your dealer can show
you how to do this.
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L
WATER
IN
FUEL
If the light comes on at any other time, use this chart. This light also should
come on briefly when
you start your engine,
as
a check. If it
doesn’t, have it fixed
so it will be there to
let you know if you
ever do get water in
your fuel.
If you drive when this warning light is on, you can damage your
fuel injection system and your engine.
If the light comes on right
after you refuel,
it means water was pumped into your fuel tank.
Turn
off your engine immediately. Then, have the water drained
at once.
“WATER IN FUEL” LIGHT CHART
Problem Recommended Action
Light comes on intermittently. Drain water from fuel filter.
Light stays on:
1. At temperatures above freezing.
2. At temperatures below freezing.
3. Immediately after refueling -
large amount of water possibly
pumped into
fuel tank. Drain fuel filter
immediately.
If no
water can be drained and light stays
on, see your dealer for assistance.
Drain fuel filter immediately.
If no
water can be drained-water may
be frozen. Open the air bleed valve
to check for fuel pressure.
If no fuel
pressure is present, replace the fuel
filter.
Fuel tank purging required. See
your dealer for assistance.
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Hesitation or “flat” performance at high speed or during \
hard acceleration
may be an indication of premature fuel filter plugging due to dirty or
contaminated fuel. The fidter element may need to be changed
if this
happens. See your dealer for assistance.
To drain water:
1. Stop and park the vehicle in a safe place. Turn off the engine and apply
2. Remove the fuel tank cap.
the parking brake.
3. Place a
fuel-resistant container under the filter drain hose.
5.
6.
7.
8.
4. With the engine
off, open the
water drain valve
2 to 3 turns.
When standing in
front of the
vehicle, the valve
is located on the
right side of the
thermostat
housing.
Start the engine and allow it to idle until clear fuel is ob\
served.
Stop the engine and close the water drain valve.
Remove the fuel-resistant container and properly dispose of the
contaminated fuel.
To find out how to properly dispose of contaminated
diesel fuel see “What to Do with Used Oil” in the “E\
ngine Oil (Diesel
Engines)” part, later in this section.
Install the fuel tank cap.
If the WATER IN FUEL light comes on again after driving a short distance
or the engine runs rough or stalls-a large amount of water has probably
been pumped into the
fuel tank. The fuel tank should be purged.
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