PONTIAC FIERO 1988 Service Repair Manual

6B-10 ENGINE COOLING
Fig. 10 Pressure Testing Radiator
containing clean water is strongly recommended
for servicing aluminum-plastic radiator.
I. Install test fittings or rubber test caps in the inlet
and outlet necks and seal the oil cooler fittings
with metal plugs to protect the cooler and keep
the fluid from running out (Fig.
11).
2. Attach pressure tester and gradually apply air
pressure until 20 psi (1
38 kPa) is attained. Do not
exceed 20 psi (138
kPa). Check pressure gage to
see if there is a pressure loss. To ensure that there
are no small leaks, run water over the repair area
and look for bubbles.
(A mild detergent is very
helpful).
If a large water tank is available, the radiator can
be submerged, and a check for air bubbles can be
made.
Fig. I I Aluminum Radiator and Oil Cooler Plugs
Repairable Leaks
There are two types of leaks that can be repaired
on the aluminum-plastic radiator: core leaks and
gasket leaks. Leaks in the plastic tanks cannot be
repaired.
L1_] INLET TANK GASKET
11_] CORE TUBES
OUTLET TANK GASKET
DRAIN COCK GASKET
OIL COOLER GASKETS
JOINT BETWEEN TUBE AND HEADER
Fig. 12 Possible Leak Areas
Repair Methods
There are several methods that can be used to
repair the radiator core, but the hot melt adhesive
method has been found to be the most simple and
effective.
The kit contains adhesive sticks, cotton swabs,
wire brush and primer. The adhesive stick is reusable,
has an indefinite shelf life, and is waste-free. The sticks
must be stored in a sealed container to keep them dry
(Fig. 13).
Fig. 13 Hot Melt Adhesive Repair Kit
Core leaks can occur in a tube, or in the joints special preparation between the tubes and headers. Gasket leaks can occur
in the joints between the plastic tanks and the headers,
cooling Fin Removal or in the joints between the oil cooler fittings and the
tank. Some leaks can be repaired while the radiator is For
damaged areas that are between the cooling
on the car; however, it is usually best to remove the fins,
it may be necessary to remove some of the fins. Do
radiator. not remove more fins
than necessary. Usually
6mm

(1/4") beyond the leak or damage area is enough to
make an effective repair. (Fig. 14).
d""U,"
Fig. 14 Fins Removed from Damaged Area
Tube Blocking
If a tube is severely damaged, it can be blocked
off. (Fig. 15).
NOTICE: DO NOT BLOCK OFF MORE
THAN TWO TUBES IN A RADIATOR.
BLOCKING OFF MORE THAN TWO TUBES
WILL REDUCE THE COOLING
CAPABILITY OF THE SYSTEM.
The tube should be cut off 6mm
(1/4") from the
header and pinched shut before it is cleaned and sealed.
(See General Core Sealing).
CUT
TUBE
Fig. 15 Tube Blocking
Header Repair
If the header or a tube near the header requires
a repair, the side tank does not have to be removed.
A
damp cloth can be placed against the side tank where
the repair has to be made (Fig. 16). The side tank can
also be submerged in a tank of water up to the header
(Fig. 17).
NOTICE: One of these procedures has to be used
when repairs are made on or near the header, to
prevent damage to the tank or gasket.
General Gore Repair
Preparation of the surface in the repair area
cannot be overemphasized. If the leak area surface is
ENGINE COOLING 6B-11
Fig. 16 Using Wet Cloth on Side Tank
not clean, none of the repair materials will stick to the
surface.
1. Position the core so the repair area is accessible.
2. Apply a wet cloth if you are working near the
plastic tanks or the joints between the core tubes
and header (Fig. 16); or submerge the tank in
water (Fig. 17).
SUBMERGE TANK -
Fig. 17 Submerging Side Tank
3. Heat the repair area slightly with a small torch or
heat gun to be sure it is dry.
Do not use a blow
torch.
4. Brush
the area to be repaired with the small steel
brush that is supplied in the kit and blow dust
away from repair area. (See Fig. 18).
5. Open
the tube of primer, using the spurred cap or
a pin, and apply primer to the repair area only.
Use of the primer produces a stronger repair.
Do
not heat the primer.
CAUTION: The primer contains
trichlorethane.
aa It could be harmful, or fatal, if
swallowed. If swaIIowed, gel
medical attention.

88-12 ENGINE COOLING
Fig. 18 Cleaning Area With Steel Brush
e Use with adequate ventilation.
In case of eye contact, flush with
plenty of water and get medical
attention.
In case of body
contact, wash
thoroughly with soap
and water.
Do not
mix the primer with water.
6. Scrub the repair area with a cotton swab until a
fresh swab stays clean. The clear, yellow-brown
coating does not have to be removed (Fig. 19).
Fig. 19 Scrubbing Area with Primer
7. Heat the repair area with the heat gun or by
moving the torch in a circular pattern (Fig. 20).
Use a soft, small blue flame (like a gas stove
flame).
8. Withdraw the torch and rub the adhesive stick on
the repair area (Fig. 21). The adhesive will flow
at a temperature of approximately 500°F (260°C).
If the stick doesn't start to melt, remove it and
reapply the heat.
Do not heat the stick
directly with
a flame. High heat will burn
and
char the adhesive.
9. Continue heating until the adhesive flows and
wets the entire repair area and fills the joint. If a
hole is in the center of a tube, heat the tube and
let the hot surface melt and pull in the adhesive.
The force of the flame or heat gun will also tend
to guide the adhesive toward the hole. For leaks
between a tube and header, flow the adhesive
completely around the tube and header joint with
the tank installed.
Fig. 20 Heating the Repair Area
I
Fig. 21 Applying Hot Melt Adhesive I
10. Heat the repair area until the adhesive is
bubble-free and smooth, with a light yellow color.
Curing is not required.
11. Test the radiator for leaks, when cool. If the
repair area still leaks, reheat it gently to dry it.
Heat and
reflow the adhesive, or apply more as
necessary, to repair the leak.
Tank Gasket beak Repair I 1
Tank gasket leaks can easily be mistaken for tank or
header leaks. If a plastic tank leaks from the header joint
gasket, tighten the clinch tabs with locking-type pliers
(Fig. 22). If this method doesn't seal the leak, remove the
tank for further inspection.
1. Pry open the clinch tabs, except those under inlet,
outlet, and filler necks, using
J33419-A or a screw-
driver (Fig.
23). Lift tabs only enough to allow
removal.
NOTICE: Care should be taken not to overbend
tabs. Overbending could result in breakage. If
there are more than
3 tabs broken on one side of
the header, or more than
2 adjacent tabs together,
the core must be replaced.
2. Lift the tank and slide it out from under the
remaining clinched tab. You may have to tap the

ENGINE COOLING 6B-13
Fig. 22 Tightening Clinch Tabs
Fig.
23 Opening Clinch Tabs
tank with your hand to dislodge the gasket. Lift
the remaining
tab(s) with pliers.
Remove and discard the gasket.
Clean the header and gasket groove of all dirt and
old rubber.
Clean the sealing edge of the plastic tank.
Examine the header gasket surface and tank
flange for evidence of leakage, and clean or repair
the surface to remove dirt, burrs, and bumps.
Remove the oil cooler, if equipped, and install it
in the new tank.
Dip or coat the new
tank gasket in engine coolant
and position it on the header surface. The coolant
helps hold the gasket in place.
Position the tank and gasket to the header, clamp
it in place and secure it by bending four clinch
tabs as shown
in Fig. 24.
Clamp remaining clinch tabs around the header
using the clinching tool or pliers (Fig.
25).
BEND FOUR CLINCH TABS
Fig. 24 Seating Tank to Core
Fig.
25 Clinching Sequence
NOTICE: Tighten the clinch tabs as you would
cylinder head bolts, starting at the center and
working out to the ends.
1 1. Replace the core if there are more than three tabs
broken on one side or two adjacent tabs broken.
12. Install the drain cock, if removed.
13. Test the radiator for leaks.
Oil Cooler Gasket Replacement
The outlet tank must be removed to replace the
oil cooler, but the oil cooler gaskets can be replaced
without removing the tank.
1. Remove the radiator and lay it on a flat surface.
2. Remove the bottom oil cooler nut and loosen the
top nut.
3. Press the oil cooler into the hole and remove the
gasket using a small hook (Fig. 26).
4. Blow-dry all surfaces on the tank and oil cooler.
5. Install a new gasket without lubrication. Be
sure it is seated properly inside the lip of the
fitting.
Reach into the inlet or outlet opening and push
the oil cooler into position against the tank.
Assemble the oil cooler nut loosely.
Replace the other gasket by following the same
procedure.
Install the oil cooler nuts and torque to
20 N.m
(15 lb. ft.). Do not overtighten, as damage to the
gasket could result.
Leak-test the radiator.

6B-I4 ENGINE COOLING
SMALL
586826
Fig. 26 Removing Oil Cooler Gasket
4. Remove old rubber gaskets, throw away, clean
and dry seal areas.
5. Place rubber gaskets on a new oil cooler and place
onto outlet tank fitting holes, being careful not to
loosen or misalign gaskets. Gaskets must be
installed dry and free of dirt and oil.
6. Install
and tighten nuts snugly onto fittings.
7. Torque nuts
to 20
N.m (15 lb. ft.). Overtorquing
could cut the rubber gaskets.
8. Replace
tank as previously described.
9. Test radiator.
Recore
If the radiator core is damaged beyond repair and
the other parts are serviceable, install the original inlet
and outlet tanks, oil cooler, radiator cap, and drain
valve, onto a new core and install new gaskets.
Drain Cock
Oil Cooler Replacement If the drain cock does not seal when tightened
snugly, remove the drain cock, clean drain and replace.
1. Remove
the outlet tank as previously outlined. If
the body of the draincock is broken, remove the body
from the tank by squeezing the sides together with
2. Remove nuts from the oil cooler fittings.
needle nose pliers (Fig. 9).
Remove oil cooler and gaskets from tank. Special Tools
Special tools are available through normal
channels for servicing the aluminum-plastic radiator.
The universal Cooling System and Cap Pressure
Tester, BT-7518 or J-24460-01, can also be used with
the aluminum-plastic radiator.
ON-VEHICLE SERVICE
THERMOSTAT
Remove or Disconnect
1. Battery negative cable at battery.
2. Air cleaner.
3. Drain cooling system.
4. Thermostat housing attaching bolts and remove
housing. Remove thermostat from manifold.
Clean
Clean housing and manifold sealing
surfaces.
Install or Connect
1. New gasket.
2. Thermostat in intake manifold.
3. Refer
to Section 6E3 for plenum and throttle
body installation.
4. Battery negative cable.
5. Fill cooling system.
6. Start engine and run, with radiator cap removed,
until radiator upper hose becomes hot
(thermostat open). 7.
With
engine idling, add coolant to radiator until
level reaches bottom of filler neck.
8. Cap making sure arrows line up with overflow
tube.
18-24 N,m (13-18 FT. LBS.)
Fig. 601 Thermostat - V.I.N. S

ENGINE COOLING 6B-15
1. 27 N-m (20 LBS. FT.)
2. 34 N.m (25 LBS. FT.)
Fig. 602 Thermostat - V.I.N. E, F and 8
ELECTRIC COOLING FAN
CAUTION: Keep hands, tools, and
clothing away from engine cooling fan
to help prevent personal injury. This
fan is electric and can come on
whether or not the engine is running.
The fan can start automatically in
response to a heat sensor with the
ignition in the "On" position.
Remove or Disconnect
1. Negative battery cable.
2. Harness from fan motor and fan frame.
3. Fan
frame to radiator support attaching bolts.
4. Fan and frame assembly.
Install or Connect
1. Fan and frame assembly.
2. Fan frame to radiator support attaching bolts and
torque to specification.
3. Harness
to fan frame and fan motor.
4. Negative battery cable.
Inspect
For proper completion of repairs.
For operation of fan motor.
WATER PUMP
Remove or Disconnect
1. Battery negative cable at battery.
2. Cooling system.
3. If equipped with M.F.I., remove air intake tube
and mass air flow sensor.
4. Fan and radiator upper support, as applicable.
5. Serpentine belt.
6. Generator upper and lower brackets, A/C brace
and bracket and, if equipped, power steering
pump lower bracket from water pump and swing
aside.
7. Radiator lower hose and heater hose from water
Pump.
8. Water pump to block attaching bolts and remove
water pump.
Install or Connect
s If installing a new water pump, transfer
heater hose fitting from old unit.
With clean sealing surfaces on both block and water
pump, install water pump to block with new gaskets
and retain with attaching bolts. Torque to specifica-
tions. (V6 small bolt
10N.m, 7 lb. ft., large bolt and
nut 20
N-m, 15 lb. ft.) (V8-40 Nsm, 30 lb. ft.)
Radiator lower hose and heater hose to water pump
and torque clamps to 2
N.m (20 lb. in.).
Generator upper and lower brackets and, if
equipped, the power steering pump lower bracket to
the water pump. Torque bolts to 41
N.m (30 lb. in.).
Serpentine belt.
If equipped with M.F.I., install air intake tube
and mass air flow sensor.
Fan and radiator upper support, as applicable.
Battery negative cable.
Fill cooling system with an ethylene glycol
antifreeze and water mixture of
50/50.
Start engine and run, with radiator cap removed,
until radiator upper hose becomes hot
(thermostat open).
With engine idling, add coolant to radiator until
level reaches bottom of filler neck.
Cap, making sure arrows line up with overflow
tube.
Fig. 603 Fan Mounting V.I.N. E, S (All) F, 8 (wlo A/C)

6B-16 ENGINE COOLING
Fig. 604 Fan Mounting - V.I.N. F and 8 (with A/C)
1. 41 N-m (30 LBS. FT.)
Fig. 605 Water Pump Mounting -- V.I.N. S Fig. 606 Water Pump Mounting - V.I.N. E, F and 8
COOLANT RECOVERY EDOUTLE
Remove or Disconnect
1. Hose from recovery bottle.
2. Attaching screws and remove bottle.
Clean Install
or Connect
1. Place bottle in vehicle and torque attaching
screws to
3 N-m (27 1b.in.).
2. Coolant hose to bottle.
3. Fill bottle to appropriate mark.
@ Recovery bottle with suitable solution.

ENGINE COOLING 68.17
RADIATOR
Remove or Disconnect
1. Negative battery cable.
2. Engine coolant.
3. Fan blade. On fan clutch equipped cars, store
clutch in upright position to prevent seal leakage.
4. Upper and lower radiator hoses.
5. On vehicles equipped with automatic
transmission, plug transmission cooler lines.
6. Fan shield assembly, if applicable.
7. Radiator and shroud assembly, lift straight up.
The radiator assembly is held at the bottom by
two cradles secured to the radiator support.
Install or Connect
1. If new radiator, transfer fittings from old radiator
to new radiator.
Radiator in car, locating bottom of radiator in
lower mounting pads.
Transmission/Engine oil cooler lines at radiator.
Coolant recovery bottle hose at radiator.
Coolant hoses at radiator.
6. Upper radiator support bracket.
7. Engine coolant.
8. Negative battery cable.
Inspect -
e For proper completion of repair.
e For fluid leaks.

88-18 ENGINE COOLING
THE INDICATOR MARK ON THE MOVEABLE PORTION OF
THE TENSIONER MUST BE WITHIN THE LIMITS OF THE
SLOTTED AREA ON THE STATIONARY PORTION OF THE
TENSIONER. ANY READING OUTSIDE THESE LIMITS INDI-
CATES EITHER A DEFECTIVE BELT OR TENSIONER.
Fig. 608 Belt Tensioner - V.I.N. S
1. USED BELT ACCEPTABLE WEAR RANGE
2. NEW BELT RANGE
5. FIXED BELT LENGTH INDICATOR
6. WITH NEW BELT INSTALLED, FIXED POINTER
MUST FALL WITHIN THIS RANGE
7. MINIMUM LENGTH - NEW BELT
8. NOMINAL LENGTH - NEW BELT
9. MAXIMUM LENGTH - NEW BELT
10. REPLACE BELT POSITION
Fig. 609 Belt Tensioner - V.I.N. E, F and 8

ENGINE COOLING 6B-19
1. TENSIONER ASSEMBLY
2. ROTATE TENSIONER IN DIRECTION
SHOWN TO INSTALL OR REMOVE BELT
3. GENERATOR ASSEMBLY
4. ACCESSORY DRIVE BELT
5. PIS PUMP
6. WATER PUMP
7. CRANKSHAFT
8. A.I.R. PUMP
Fig. 610 Belt Diagram - V.I.N. E, F and 8
1. GENERATOR 5. WATER PUMP
2. TENSIONER 6. CRANKSHAFT
3. BELT 7. A.I.R. PUMP
4. PIS PUMP 8. AIC COMPRESSOR J10009-68-F
Fig. 611 Belt Diagram -- V.I.N. S (Manual Transmission)