Maintain the coolant level at
3
/
4
to 1
1
/
2
inches bellow the filler neck
seat of the radiator when the coolant is cold. When ever coolant
level checks are made inspect the condition of the radiator cap
rubber seal. Make sure it is clean and free of any dirt particles which
would keep it from seating on the filler neck seat. Rinse off with
clean water if necessary. Also make sure that the filler neck seat
is free of any dirt particles.
WARNING
Never remove the radiator cap under any conditions
while the engine is operating. Failure to follow these
instruction could result in damage to the cooling system,
engine, or cause personal injury. To avoid having scalding
hot coolant or steam blow out of the radiator, use extreme
caution when removing the radiator cap from a hot
radiator. I f possible, wait until the engine has cooled,
then wrap a thick cloth around the radiator cap and turn
slowly to the first stop. Step back while the pressure has
been released, press down on the cap and remove it
slowly.
DO NOT add coolant to any engine that has become
overheated until the engine cools. Adding coolant to an
extremely hot engine can result in a cracked block or
cylinder head.
Use only a permanent-type coolant when refilling or flushing the
coolant system. Recommended ethylene glycol mix 52/48 is normal
up to a maximum of 60% glycol, 40% water. Refer to the mixture
chart on the container for additional antifreeze protection
information. DO NOT use alcohol or methanol antifreeze, or mix
them with the specified coolant.
Plain water may be used in an emergency (except in freezing
temperatures), but replace it with the specified coolant as quickly
as possible to avoid damage to the system.
Radiator
Inspect the exterior of the radiator for obstructions. Remove all
bugs, dirt or foreign material with a soft brush or cloth. Use care
to avoid damaging the core fins. If available, use low pressure
compressed air or a stream of water in the opposite direction of
the normal air flow. Check all hoses and connections for leaks. If
any of the hoses are cracked, frayed, or feel spongy, they must be
replaced.
Fan Belts
The water pump is usually belt driven. The same belt may also drive
the fan/or the alternator. The drive belts should be properly adjusted
at all times. A loose belt can cause improper alternator, fan and
water pump operation, in addition to overheating.
Serpentine Belt
Some GM
Powertrain
engines utilize serpentine belts on the front
of the engine. This type of belt system incorporates a belt tensioning
device which keeps the belt at the proper tension. This belt should
be checked routinely for cracks or checking on the groove side
of the belt. If cracks or checking are apparent the belt must be
changed.
V-Type Belt
V-Type belts are generally tensioned by adjusting the alternator, or
through a mechanical belt tensioner. The belt is generally correctly
tensioned when three is an
1
/
2
inch of depression on the belt
between the water pump and the crankshaft pulley.
.7 Ignition Systems
Types of Ignition Systems
Three types of ignition systems are used on PSI GM
Powaetrain
engines. Solid state electronic distributor with ECU (Electronic
Control Unit) and distributor-less electronic ignition with ECU. Please
refer to the General Specification chart to determine the ignition
system used on your particular engine.
IgnitionTiming
Proper adjustment of the ignition timing must be obtanied to
provide the optimum engine power output and economy.
To properly adjust timing refer to the timing procedure section of
this manual.
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