check engine FORD FESTIVA 1991 Service Manual

SERVICE & ADJUSTMENT SPECIFICATIONS
If you want a specification quickly, this is the place to look. Instead of hunting through a long article, we've separated out the important
specifications and arranged them into easy-to-use tables in a centralized location. You can find valuable information like spark plug wire
resistance, valve clearance, timing, firing orders, etc.
ADJUSTMENT
ON-VEHICLE ADJUSTMENTS
The ON-VEHICLE ADJUSTMENTS article contains the type of information that was previously thought of as TUNE-UP information.
Procedures for checking and adjusting valves, base ignition timing and idle speed are found in this section. Use this section in conjunction with
SERVICE & ADJUSTMENT SPECIFICATIONS for performing routine maintenance. Also, if you have a driveability problem, ensure all on-
vehicle adjustments are within specification before attempting further diagnosis.
THEORY & OPERATION
This article covers basic THEORY & OPERATION of engine performance-related systems and components. Before diagnosing vehicles or new
systems with which you are not completely familiar, read this article.
TESTING & DIAGNOSTICS
BASIC DIAGNOSTIC PROCEDURES/BASIC TESTING
The procedures listed in this article can help you avoid skipping a simple step early, like checking base timing, which could be costly in both
time and money later. This is also a potential starting point for diagnosis of a "no-start" condition. If all systems check out okay here, proceed
to SELF-DIAGNOSTICS/TESTS W/CODES or TROUBLE SHOOTING - NO CODES/TESTS W/O CODES article.
SELF-DIAGNOSTICS/TESTS W/CODES
Use this information to retrieve and interpret Diagnostic Trouble Codes (DTCs) accessed from the vehicle's self-diagnostic system. Once
information is retrieved, manufacturer diagnostic procedures are given to help pinpoint and repair computer system/component faults. Also
included are steps for clearing trouble codes once these faults are repaired. If there is a driveability symptom with no trouble codes set,
proceed to TROUBLE SHOOTING - NO CODES/TESTS W/O CODES article.
TROUBLE SHOOTING - NO CODES/TESTS W/O CODES
This is where to go when you have a problem that does not set a trouble code. It can help determine cause of problem using driveability
symptoms and intermittent testing procedures. Procedures in this information should lead you to a specific component or system test.
SYSTEM & COMPONENT TESTING
Here you will find various tests for engine performance systems and their components, such as air induction (turbochargers and superchargers),
fuel control, ignition control and emission systems.
PIN VOLTAGE CHARTS
These are supplied (when available from manufacturer) to quicken the diagnostic process. By checking pin voltages at the Powertrain Control
Module (PCM), you can determine if the PCM is receiving and/or transmitting proper voltage signals. Pin charts may also be referred to as PID
charts by some manufacturers.
SENSOR RANGE CHARTS
SENSOR OPERATING RANGE CHARTS
These are supplied (when available from manufacturer) to determine if a sensor is out of calibration. An out-of-calibration sensor may not set a
trouble code, but it may cause driveability problems.
VACUUM DIAGRAMS
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
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GENERAL INFORMATION
Parasitic Load Explanation & T est Procedures
* PLEASE READ THIS FIRST *
GENERAL INFORMATION
The term Parasitic Load refers to electrical devices that continue to use or draw current after the ignition switch is turned to OFF position. This
small amount of continuous battery draw is expressed in milliamps (mA). On Chrysler vehicles, a typical Parasitic Load should be no more
than 30 milliamps (0.030 amps). On Ford Motor Co. and General Motors vehicles produced after 1980, a typical Parasitic Load should be no
more than 50 milliamps (0.050 amps).
Vehicles produced since 1980 have memory devices that draw current with ignition off for as long as 20 minutes before shutting down the
Parasitic Drain. When Parasitic Load exceeds normal specifications, the vehicle may exhibit dead battery and no-start condition.
Follow test procedure for checking Parasitic Loads to completion. A brief overview of a suggested test procedure is included along with some
typical Parasitic Load specifications. Refer to GENERAL MOTORS PARASITIC LOAD TABLE chart.
TESTING FOR PARASITIC LOAD
The battery circuit must be opened to connect test switch (shunt) and ammeter into the circuit. When a battery cable is removed, timer circuits
within the vehicle computer are interrupted and immediately begin to discharge. If in doubt about the condition of the ammeter fuse, test it
with an ohmmeter prior to beginning test. An open fuse will show the same reading (00.00) as no parasitic drain. Begin test sequence with the
meter installed and on the 10-amp scale. Select lower scale to read parasitic draw.
CHRYSLER IGNITION OFF DRAW (IOD) TEST
To test for excessive IOD, verify that all electrical accessories are OFF. Turn off all lights, remove ignition key, and close all doors and decklid.
If the vehicle is equipped with electronic accessories (illuminated entry, automatic load leveler, body computer, or high line radio), allow the
system to automatically shut off (time out), up to 3 minutes.
1. Raise the hood and disconnect both battery cables, negative first.
2. Reconnect the negative cable and connect a typical 12-volt test light (low wattage bulb) between the positive cable clamp and the
positive battery post. Remove the engine compartment lamp bulb. If the test light does not light, proceed to step 3
. If the test light does
light, proceed to step, 4
. The test light will indicate IOD greater than 3 amps. After higher amperage IOD has been corrected, proceed to
step 3
.
3. ith 12-volt test light still connected (not lit), connect an ammeter (milliampere scale) between the positive cable clamp and the positive
battery post, disconnect test light, refer to instructions provided with ammeter being used. A reading of 30 milliamperes or less indicates
normal electrical draw. If ammeter reads more than 30 milliamperes, excessive IOD must be corrected.
4. Locate the fuse panel and remove fuses or circuit breakers one at a time, and observe ammeter after each fuse or circuit breaker is
removed. If test light goes out and the reading drops below 30 milliamperes when a certain fuse or circuit breaker is removed, that circuit
may have a defect.
5. If IOD is detected after all fuses and circuit breakers have been removed, disconnect the 60-way connector at the Single Module Engine
Control (SMEC), located outboard of the battery.
6. If excessive IOD is detected after all fused circuits and SMEC have been verified, disconnect the B+ terminal from the alternat o r. If
reading drops below 30 milliamperes, reinstall all fuses and circuit breakers, reconnect B+ terminal at alternator, reconnect battery, and
perform alternator diagnostics.
7. Install engine compartment lamp bulb.
TEST PROCEDURE USING TEST SWITCH
1. Turn ignition off. Remove negative battery terminal cable. Install Disconnect Tool (J-38758) test switch male end to negative battery
cable. Turn test switch knob to OFF position (current through meter). Install negative battery cable to the female end of test switch. NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. For m odel-specific inform ation see appropriate articles where
available.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. For m odel-specific inform ation see appropriate articles where
available.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. For m odel-specific inform ation see appropriate articles where
available.
CAUT ION: Always turn ignition off when connecting or disconnecting battery cables, battery chargers or jum per
cables. DO NOT turn test switch to OFF position (which causes current to run through am m eter or
vehicle electrical system ).
NOTE:Mem ory functions of various accessories m ust be reset after the battery is reconnected.
CAUT ION: IOD greater than 3 am ps m ay dam age m illam pm eter.
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Since DVOMs update their display roughly two to five times a second, all measurements in between are averaged. Because a potential voltage
drop is visible for such a small amount of time, it ge t s "a ve r a ge d o u t ", c a u sin g yo u t o miss it .
Only a DVOM that has a "min-max" function that checks EVERY MILLISECOND will catch this fault consistently (if used in that mode). The
Fluke 87 among others has this capability.
A "min-max" DVOM with a lower frequency of checking (100 millisecond) can miss the fault because it will probably check when the injector
is not on. This is especially true with current controlled driver circuits. The Fluke 88, among others fall into this category.
Outside of using a Fluke 87 (or equivalent) in the 1 mS "min-max" mode, the only way to catch a voltage drop fault is with a lab scope. You
will be able to see a voltage drop as it happens.
One final note. It is important to be aware that an injector circuit with a solenoid resistor will always show a voltage drop when the circuit is
energized. This is somewhat obvious and normal; it is a designed-in voltage drop. What can be unexpected is what we already covered--a
voltage drop disappears when the circuit is unloaded. The unloaded injector circuit will show normal battery voltage at the injector.
Remember this and do not get confused.
Checking Injector On-Time With Built-In Function
Several DVOMs have a feature that allows them to measure injector on-time (mS pulse width). While they are accurate and fast to hookup,
they have three limitations you should be aware of:
They only work on voltage controlled injector drivers (e.g "Saturated Switch"), NOT on current controlled injector drivers (e.g. "Peak &
Hold").
A few unusual conditions can cause inaccurate readings.
Varying engine speeds can result in inaccurate readings.
Regarding the first limitation, DVOMs need a well-defined injector pulse in order to determine when the injector turns ON and OFF. Voltage
controlled drivers provide this because of their simple switch-like operation. They completely close the circuit for the entire duration of the
pulse. This is easy for the DVOM to interpret.
The other type of driver, the current controlled type, start off well by completely closing the circuit (until the injector pintle opens), but then
they throttle back the voltage/current for the duration of the pulse. The DVOM understands the beginning of the pulse but it cannot figure out
the throttling action. In other words, it cannot distinguish the throttling from an open circuit (de-energized) condition.
Yet current controlled injectors will still yield a millisecond on-time reading on these DVOMs. You will find it is also always the same,
regardless of the operating conditions. This is because it is only measuring the initial completely-closed circuit on-time, which always takes the
same amount of time (to lift the injector pintle off its seat). So even though you get a reading, it is useless.
The second limitation is that a few erratic conditions can cause inaccurate readings. This is because of a DVOM's slow display rate; roughly
two to five times a second. As we covered earlier, measurements in between display updates get averaged. So conditions like skipped injector
pulses or intermittent long/short injector pulses tend to get "averaged out", which will cause you to miss important details.
The last limitation is that varying engine speeds can result in inaccurate readings. This is caused by the quickly shifting injector on-time as the
engine load varies, or the RPM moves from a state of acceleration to stabilization, or similar situations. It too is caused by the averaging of all
measurements in between DVOM display periods. You can avoid this by checking on-time when there are no RPM or load changes.
A lab scope allows you to overcome each one of these limitations.
Checking Injector On-Time With Dwell Or Duty
If no tool is available to directly measure injector millisecond on-time measurement, some techs use a simple DVOM dwell or duty cycle
functions as a replacement.
While this is an approach of last resort, it does provide benefits. We will discuss the strengths and weaknesses in a moment, but first we will
look at how a duty cycle meter and dwell meter work.
How A Duty Cycle Meter and Dwell Meter Work
All readings are obtained by comparing how long something has been OFF to how long it has been ON in a fixed time period. A dwell meter
and duty cycle meter actually come up with the same answers using different scales. You can convert freely between them. See
RELATIONSHIP BETWEEN DWELL & DUTY CYCLE READINGS TABLE
.
The DVOM display updates roughly one time a second, although some DVOMs can be a little faster or slower. All measurements during this
update period are tallied inside the DVOM as ON time or OFF time, and then the total ratio is displayed as either a percentage (duty cycle) or
degrees (dwell meter).
For example, let's say a DVOM had an update rate of exactly 1 second (1000 milliseconds). Let's also say that it has been measuring/tallying
an injector circuit that had been ON a total of 250 mS out of the 1000 mS. That is a ratio of one-quarter, which would be displayed as 25%
duty cycle or 15° dwell (six-cylinder scale). Note that most duty cycle meters can reverse the readings by selecting the positive o r n e ga t ive
slope to trigger on. If this reading were reversed, a duty cycle meter would display 75%.
Strengths of Dwell/Duty Meter
The obvious strength of a dwell/duty meter is that you can compare injector on-time against a known-good reading. This is the only practical
way to use a dwell/duty meter, but requires you to have known-good values to compare against.
Another strength is that you can roughly convert injector mS on-time into dwell reading with some computations.
A final strength is that because the meter averages everything together it does not miss anything (though this is also a severe weakness that we
will look at later). If an injector has a fault where it occasionally skips a pulse, the meter registers it and the reading changes accordingly.
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Fig. 7: Single Injector w/Excessive Current Flow
- Current Pattern
EXAMPLE #2 - VOLTAGE CONTROLLED DRIVER
This time we will look at a GM 3.1L V6 VIN [T]. Fig. Fig. 8
shows the 1, 3, 5 (odd) injector bank with the current waveform indicating about
a 2.6 amp draw at idle. This pattern, taken from a known good vehicle, correctly stays at or below the maximum 2.6 amps current range.
Ideally, the current for each bank should be very close in comparison.
Notice the small dimple on the current flow's rising edge. This is the actual injector opening or what engineers refer to as the "set p o in t . " Fo r
good idle quality, the set point should be uniform between the banks.
When discussing Ohm's Law as it pertains to this parallel circuit, consider that each injector has specified resistance of 12.2 ohms. Since all
three injectors are in parallel the total resistance of this parallel circuit drops to 4.1 ohms. Fourteen volts divided by four ohms would pull a
maximum of 3.4 amps on this bank of injectors. However, as we discussed in EXAMPLE #1
above, other factors knock this value down to
roughly the 2.6 amp neighborhood.
Now we are going to take a look at the even bank of injectors; injectors 2, 4, and 6. See Fig. 9. Notice this bank peaked at 1.7 amps at idle as
compared to the 2.6 amps peak of the odd bank (Fig. Fig. 8
). Current flow between even and odd injectors banks is not uniform, yet it is not
causing a driveability problem. That is because it is still under the maximum amperage we figured out earlier. But be aware this vehicle could
develop a problem if the amperage flow increases any more.
Checking the resistance of this even injector group with a DVOM yielded 6.2 ohms, while the odd injector group in the previous example read
4.1 ohms.

Fig. 8: Injector Odd Bank w/Normal Current Flow
- Current Pattern

Fig. 9: Injector Even Bank w/Normal Current Flow
- Current Pattern
EXAMPLE #3 - VOLTAGE CONTROLLED DRIVER
Example #3 is of a Ford 5.0L V8 SEFI. Fig. Fig. 10
shows a waveform of an individual injector at idle with the Lab Scope set on 200
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1991 GENERAL SERVICING
A/C Com pressor Refrigerant Oil Checking
ISOLATING COMPRESSOR
1. Connect service gauge set to the compressor service valves and open compressor valves slightly (turn in clockwise). Start engine and
operate air conditioning. Slowly turn compressor suction valve clockwise toward closed (front-seated) position.
2. When suction pressure is reduced to zero or less, turn off engine and compressor and quickly turn suction valve stem in to full front-
seated position. Suction pressure should be slightly above zero. Turn discharge valve into front-seated position.
3. To check oil level, slowly open compressor crankcase plug to relieve any remaining pressure. After oil level is corrected, cap service
gauge ports on both valves. Back-seat suction service valve to allow refrigerant to enter compressor. Open discharge valve halfway.
4. Loosen discharge service valve cap, allowing refrigerant pressure to force air out of compressor. Back-seat service valve and tighten cap.
Compressor is now ready for operation.
REFRIGERANT OIL
Only new, pure, moisture-free refrigerant oil should be used in the air conditioning system. This oil is highly refined and dehydrated to a point
where moisture content is less than 10 parts per million. The oil container must be tightly closed at all times when not in use, or moisture will
be absorbed into the refrigerant oil from the air.
SERVICING PRECAUTIONS
DISCHARGING SYSTEM PRECAUTIONS
If compressor has stem-type service valves, it can be isolated and removed without discharging entire system. See ISOLATING
COMPRESSOR at the beginning of this article. Otherwise, discharge system completely before loosening any fittings.
DISCONNECTING LINES & FITTINGS TEST
After system is discharged, carefully clean area around all fittings to be opened. Always use 2 wrenches when tightening or loosening fittings
to avoid twisting or distorting lines. Cap or plug all openings as soon as lines are removed. DO NOT remove caps until immediately before
connections are made. This will keep entry of air and moisture to a minimum.
CONNECTING LINES AND FITTINGS
A new gasket or "O" ring should be used in all instances when connecting lines or fittings. Dip "O" ring in new refrigerant oil and ensure it is
not twisted during installation. Always use 2 wrenches to prevent damage to lines and fittings.
PLACING SYSTEM IN OPERATION
After component service or replacement has been completed and all connections have been made, evacuate system thoroughly with a vacuum
pump. Charge system with proper amount of refrigerant and perform a leak test. See REFRIGERANT OIL & R-12 SPECIFICATIONS chart in
this section for system capacities. Be sure to check all fittings that have been opened. After system has been leak tested, make a system
performance check.
ATSUGI ROTARY VANE DRAIN & REFILL
1. Before checking and adjusting oil level, operate compressor at engine idling speed, with controls set for maximum cooling and high
blower speed, for 20 to 30 minutes to return oil to compressor.
2. Stop engine, discharge refrigerant and remove compressor from vehicle. See SERVICING PRECAUTIONS at beginning of article. Drain
compressor oil from compressor discharge port and measure the amount. Oil is sometimes hard to drain when compressor is cool.
Remove oil while compressor is warm.
3. If the amount drained is less than 3 ounces, conduct leak tests at system connections, and if necessary, repair or replace faulty parts.
Check purity of oil and adjust oil level as follows.
4. If amount drained was above 3 ounces, oil level is right. Pour in same amount as was drained. If amount drained was below 3 ounces,
pour in 3 ounces of new refrigerant oil.
BOSCH 6-CYL DRAIN & REFILL
1. Before checking and adjusting oil level, operate compressor at engine idling speed, with controls set for maximum cooling and high
blower speed, for 20 to 30 minutes to return oil to compressor.
2. Stop engine and discharge refrigerant. Remove refrigerant oil level inspection plug on side of compressor. Oil should be at lower lip of
threaded hole. Add necessary new refrigerant oil (if low). Replace inspection plug and tighten to 10-12 ft. lbs. (14-16 N.m). NOTE:Only com pressors with stem -type service valves can be isolated.
NOTE:Recent findings by the EPA indicate that refrigerant is harm ful to the earth's protective Ozone layer.
When discharging refrigerant, DO NOT allow refrigerant to enter the atm osphere. If available, use
refrigerant recovery/recycle system s when discharging system . Always follow m anufacturer's
instructions.
NOTE:Air conditioning system s will not norm ally need addition of refrigerant oil unless definite oil loss has
occurred due to ruptured lines, leaking com pressor seals, com pressor overhaul or com ponent
replacem ent.
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CALSONIC V5 5-CYLINDER
1. Before checking and adjusting oil level, operate compressor at 1000-1500 engine RPM, and set controls at maximum cooling and
blowing speed for 20-30 minutes to return oil to compressor.
2. Stop engine. Discharge refrigerant and remove compressor from vehicle. See SERVICING PRECAUTIONS at the beginning of this
article. Drain compressor oil from compressor discharge port and measure oil amount. Oil may be hard to drain if compressor is cool.
Drain oil while compressor is warm.
3. If amount drained is less than 3.2 ounces, conduct leak tests at system connections. Repair or replace faulty parts as necessary. Check
purity of oil and oil level as follows.
4. If amount drained is more than 3.2 ounces, oil level is okay; fill with same amount drained using new oil. If amount drained is less than
3.2 ounces, pour in 3.2 ounces of new refrigerant oil.
DIESEL KIKI ROTARY VANE DRAIN & REFILL
1. Before checking and adjusting oil level, operate compressor at engine idling speed, with controls set for maximum cooling and high
blower speed, for 20 to 30 minutes to return oil to compressor.
2. Stop engine, discharge refrigerant and remove compressor from vehicle. See SERVICING PRECAUTIONS at the beginning of this
article. Drain compressor oil from compressor discharge port and measure the amount. Oil is sometimes hard to drain when compressor
is cool. Remove oil while compressor is warm.
3. If the amount is less than 2.4 ounces, conduct leak tests at system connections, and if necessary, repair or replace faulty parts. Check
purity of oil and adjust oil level as follows.
4. If amount drained was above 2.4 ounces, oil level is right. Pour in same amount as was drained. If amount drained was below 2.4
ounces, pour in 2.4 ounces of new refrigerant oil.
DIESEL KIKI 6-CYL DRAIN & REFILL
1. Before checking and adjusting oil level, operate compressor at engine idling speed, with controls set for maximum cooling and high
blower speed, for 20 to 30 minutes to return oil to compressor.
2. Stop engine, discharge refrigerant and remove compressor from vehicle. See SERVICING PRECAUTIONS at the beginning of this
article. Remove oil drain plug and drain oil. Measure amount of oil drained. Install drain plug with new "O" ring.
3. If amount drained was more than 2 ounces (4.4 ounces for Infinity), refill with same amount of new oil. If amount drained was less than
2 ounces (4.4 ounces for Infinity), refill with 2 ounces (4.4 ounces for Infinity). Install filler plug and recharge system.
FORD FX-15 6-CYLINDER DRAIN & REFILL
1. Slowly discharge system. Remove A/C compressor. Drain compressor oil from suction and discharge ports. Measure amount drained and
discard oil.
2. If amount drained from removed (old) compressor is between 3 and 5 ounces, add drained amount of new SUNINSO 5GS refrigerant oil
into the NEW compressor through suction port.
3. If amount drained is less than 3 ounces, add 3 ounces to the NEW compressor. If amount drained is more than 5 ounces, add 5 ounces.
Use new "O" rings on refrigerant lines. Install A/C compressor. Evacuate and recharge system. Perform leak test.
HARRISON 4-CYL DRAIN & REFILL
The Harrison 4-cyl compressor is charged (new) with 6 ounces of refrigerant oil. Because compressor does not have an oil sump, it should not
have to be removed for oil measurement (it retains very little oil). Note the following situations for checking and adding oil to this compressor.
NO OIL LEAK; REPLACING COMPONENTS
If only the compressor is to be replaced, remove, drain oil, measure and reinstall an equal amount of new oil. If evaporator is being replaced,
add 3 ounces of new oil. If condenser is being replaced, add one ounce.
LOSS OF REFRIGERANT OVER EXTENDED PERIOD
When a loss of refrigerant has occurred over an extended period of time and a component is being replaced to correct the leak, add an
appropriate amount of refrigerant oil to the component.
SIGNS OF EXCESSIVE OIL LEAKAGE
If system has lost excessive oil, remove accumulator. Drain and measure oil. If more than 3 ounces is measured, replace the same amount of
new oil as was drained. If less than 3 ounces is measured, add 3 ounces of new oil. Add and additional 2 ounces of new oil to compensate for
that lost by replacing the accumulator (held in desiccant).
HARRISON V5 5-CYLINDER DRAIN & REFILL
1. If system is operable, run for several minutes to stabilize system before performing repairs. Turn off engine. Discharge system and
remove compressor. See SERVICING PRECAUTIONS at the beginning of this article. Remove drain plug. Drain and measure oil. NOTE:Replacem ent FX-15 com pressors contain 7 ounces of refrigerant oil. Prior to installing com pressor,
drain refrigerant oil and determ ine proper am ount of refrigerant oil to be added.
NOTE:T he Harrison com pressor DOES NOT have an oil sum p. It's crucial that the com pressor rem ains well
oiled. It takes very little tim e to destroy this com pressor if it runs dry.
NOTE:If the exact oil charge is in doubt, drain and flush system . Add a new 6-ounce charge of refrigerant oil to
the system .
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2. If more than one ounce is drained, add same amount. If less than one ounce is drained, add 2 ounces of new refrigerant oil to
compressor.
3. If A/C components are replaced, add refrigerant oil to system. Add one ounce if condenser is replaced. Add 3.5 ounces if accumu l at o r is
replaced.
4. When replacing a component which has caused a large refrigerant leak, add 3 ounces of new oil plus the required amount for the part
being replaced. Add oil directly to part being replaced if possible. If oil can not be easily added to part, add oil to accumulator.
HITACHI 5-CYL DRAIN & REFILL
1. Before checking and adjusting oil level, operate compressor at 1000-1500 engine RPM, and set controls at maximum cooling and high
blowing speed for about 10 minutes to return oil to compressor.
2. Stop engine. Discharge refrigerant and remove compressor from vehicle. See SERVICING PRECAUTIONS at the beginning of this
article. Drain oil from compressor through suction port. Measure amount of oil drained.
3. If amount drained is more than 2.4 ounces, fill with same amount using new oil. If amount drained is less than 2.4 ounces, fill with 2.4
ounces. Install compressor and recharge.
4. If A/C components are replaced. add refrigerant oil to system. Add 1.7 ounces if condenser is replaced. Add 2.4 ounces if evaporator is
replaced. oil does not need to be added if receiver-drier is replaced.
HITACHI 6-CYL DRAIN & REFILL
1. Before checking and adjusting oil level, operate compressor at engine idling speed, with controls set for maximum cooling and high
blower speed, for 10 minutes to return oil to compressor.
2. Stop engine, discharge refrigerant and remove compressor from vehicle. See SERVICING PRECAUTIONS at the beginning of this
article. Drain oil from compressor suction port. Measure amount of oil drained. If amount drained was more than 2.4 ounces, refill with
same amount of new oil. If amount drained was less than 2.4 ounces, refill with 2.4 ounces. Install compressor and recharge.
MATSUSHITA ROTARY VANE DRAIN & REFILL
Discharge system. Remove compressor from vehicle. Drain oil from compressor through inlet and outlet holes. Refill compressor with 3.4-4.7
ounces of oil through suction port. When replacing evaporator, add 2 ounces. When replacing other A/C components, add 1.4 ounces per
component replaced.
NIPPONDENSO ROTARY VANE DRAIN & REFILL
1. Before checking and adjusting oil level, operate compressor at engine idle speed, and set controls at maximum cooling and high blowing
speed for 20-30 minutes to return oil to compressor.
2. Stop engine. Discharge refrigerant and remove compressor from vehicle. See SERVICING PRECAUTIONS at the beginning of this
article. Drain compressor oil through compressor intake and discharge ports. Measure amount drained. Oil may be hard to drain if
compressor cool. Drain compressor while compressor is warm.
3. If amount drained is less than 2.4 ounces, conduct leak tests at system connections. If necessary, repair or replace faulty parts. Check
purity of oil level and adjust oil level as follows.
4. If amount drained is more than 2.4 ounces, oil level is okay; fill with same amount drained using new oil. If amount drained is less than
2.4 ounces, pour 2.4 ounces of new refrigerant oil.
5. When replacing condenser, add one ounce. when replacing other A/C components, add .33 ounce per container replaced.
NIPPONDENSO 6 & 10-CYL DRAIN & REFILL
When inspecting system for oil loss, look for signs of leaking (shiny, wet spots on components or underside of hood). If oil leak is noted or
component replacement is required, use the following procedure as indicated:
NO OIL LEAK
Discharge system and change components as necessary. See SERVICING PRECAUTIONS at the beginning of this article. Add refrigerant oil
to components as necessary.
OIL LEAK
1. Slowly discharge system. Repair or replace faulty components. If equipped with a drain plug, remove plug, drain and discard oil. If not
equipped with a drain plug, remove compressor from vehicle and pour oil out suction and discharge ports.
2. Replace drain plug (if equipped). Add 1.5 ounces of new refrigerant oil through suction port. Use new gaskets or "O" rings when
replacing suction and discharge lines.
COMPRESSOR FAILURE OR SYSTEM CONTAMINATED
If either situation exists, discharge system and remove compressor, receiver-drier and expansion valve. Clean expansion valve screen. Flush
entire system. Install new compressor and receiver-drier. New compressors contain correct amount of oil. If installing overhauled compressor,
add 1.5 ounces of new refrigerant oil through suction port.
PANASONIC ROTARY VANE DRAIN & REFILL
1. Before checking and adjusting oil level, operate compressor at 1000-1500 engine RPM, and set controls at maximum cooling and high
blowing speed for about 10 minutes to return oil to compressor.
2. Stop engine. Discharge refrigerant and remove compressor from vehicle. See SERVICING PRECAUTIONS at the beginning of this NOTE:If oil drained contains m etal chips or other debris, replace receiver-drier. Flush out system before
evacuating and recharging.
Page 3 of 4 MITCHELL 1 ARTICLE - 1991 GENERAL SERVICING A/C Compressor Refrigerant Oil Checking
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article. Drain oil from compressor through suction and discharge ports. Measure amount of oil drained. If amount drained is more than
2.4 ounces, fill with same amount using new oil. If amount drained is less than 2.4 ounces, fill with 2.4 ounces. Install compressor and
recharge.
3. If A/C components are replaced, add refrigerant oil to system. Add 1.4 ounces if condenser is replaced. Add 2 ounces if the evaporator
is replaced. Oil does not need to be added if receiver-drier is replaced.
SANDEN SCROLL DRAIN & REFILL
Discharge system. Remove compressor from vehicle. Drain oil from compressor through inlet and outlet holes. Refill compressor with 2.8
ounces of oil through suction port. When replacing condenser, add .5 ounce. When replacing evaporator, add 1.7 ounces. When replacing
other A/C components, add .5 ounce per component replaced.
SANDEN 5-CYL DRAIN & REFILL
1. Discharge system. Remove compressor belt and loosen mounting bolts. Rotate compressor in brackets until filler plug is at top. Clean
area around filler plug and remove plug slowly. Rotate front hub plate so notch in lobe is 110 degrees from the bottom. This rotates ball
end of top piston to align with oil fill port and allows clearance for dipstick. See Fig. 1
.
2. Insert compressor dipstick diagonally from right to left until stop on dipstick contacts filler plug surface. Remove dipstick and note oil
fill level. Each increment on dipstick represents one ounce of oil. Add oil if necessary to reach 3-4 ounce level.

Fig. 1: Sanden 5
-Cylinder Oil Level Checking
Courtesy of SANDEN INTERNATIONAL U.S.A, INC.
SANDEN 7-CYL DRAIN & REFILL
1. Before checking and adjusting oil level, operate compressor at engine idle speed, and set controls at maximum cooling and high blowing
speed for 20-30 minutes to return oil to compressor.
2. Stop engine. Discharge refrigerant and remove compressor from vehicle. See SERVICING PRECAUTIONS at the beginning of this
article. Remove oil drain plug and drain oil. Measure amount of oil drained. Install drain plug with new "O" ring.
3. If amount drained is more than 3 ounces, fill with same amount using new oil. If amount drained is less than 3 ounces, fill with 3
ounces. Install filler plug. Install compressor and recharge system.
Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00038952
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Fig. 1: Exploded View of Chrysler, Ford & Nippondenso 6-Cyl Compressors
Courtesy of FORD MOTOR CO.
Installation
1. Place dowel pins in compressor. Lubricate inlet reed valve with refrigerant oil. Install inlet reed valve on compressor. Install front valve
plate assembly on compressor.
2. Lubricate shaft seal seat with refrigerant oil. Position Seat Installer (T81P-19623-C) on new seat so installer is placed on raised side of
seat. Install shaft seal seat.
3. Install shaft seal assembly in front head so sealing surface is toward en of compressor shaft. Ensure flat areas on shaft seal assembly
engage with flat areas on compressor shaft.
4. Lubricate front head "O" ring with refrigerant oil. Install front head and "O" ring. Tighten retaining bolts in a crisscross pattern to 19 ft.
lbs. (26 N.m). DO NOT use air tools to tighten retaining bolts.
5. Install clutch assembly. Add same amount new refrigerant oil to compressor as was drained. Install compressor. Evacuate and recharge
system. Perform leak test.
FORD FX-15 10-CYL CLUTCH ASSEMBLY
Removal
1. Discharge system using approved refrigerant recovery/recycling equipment. Remove compressor. Using Spanner (T70P-4067-A), remove
clutch plate retaining bolt and discard. Using an 8-mm bolt threaded into clutch plate, remove clutch plate and shims. See Fig. 2
.
2. Remove snap ring and remove pulley assembly. Disconnect electrical wiring to clutch coil. Install Shaft Protector (T89P-19623-FH) on
nose opening of compressor.
3. Install 2-jaw puller on compressor. Ensure puller screw is engaged in center of shaft protector. Tighten puller to remove clutch coil from
compressor. DO NOT use air tools when removing clutch coil.
Installation
1. Ensure clutch coil mounting surface is clean. Install clutch coil. Ensure electrical connection is correctly positioned. Install Coil
Installer (T89P-19623-EH) over compressor nose and inner diameter of clutch coil.
2. Install 2-jaw puller on compressor and coil installer. Jaws on puller should engage with compressor front mounts and pressure screw
centered on coil installer.
3. Tighten pressure screw and install clutch coil. DO NOT use air tools when installing clutch coil.
4. Install pulley and snap ring. Install snap ring with beveled side away from compressor. Install shims and clutch plate. Install NEW
clutch plate retaining bolt and tighten to 96-120 INCH lbs. (11-14 N.m).
5. Using a feeler gauge, check clearance between clutch plate and pulley assembly mating surfaces in 3 places. Clearance should be .018-
.033" (.46-.84 mm). If clearance is not correct, add or remove shims.
6. Install compressor. Evacuate and recharge system. Perform leak test.

Fig. 2: View of Ford FX
-15 10-Cyl Compressor Clutch Assembly
Courtesy of FORD MOTOR CO.
FORD FX-15 10-CYL SHAFT SEAL
Removal
CAUT ION: DO NOT dry front valve plate assem bly or inlet reed valve with com pressed air.
CAUT ION: DO NOT touch sealing surfaces of shaft seal or shaft seat assem bly.
NOTE:When new clutch assem bly is installed, cycle clutch assem bly 10 tim es with engine at idle to burnish
clutch and prevent slippage.
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NIPPONDENSO 10P13 CLUTCH ASSEMBLY
Removal
1. Discharge system using approved refrigerant recovery/recycling equipment and remove compressor. Using Clutch Holder (1014), hold
clutch plate and remove crankshaft nut. Using Clutch Plate Remover (T80L-19703-B), pull clutch plate from compressor. Remove
clutch plate shims.
2. Remove snap ring and pulley assembly. If pulley assembly cannot be removed by hand, use Shaft Protector (T80L-19703-G) and 3-jaw
puller to remove pulley. Remove snap ring. Disconnect electrical wiring and remove clutch coil.
Installation
1. Install clutch coil over locating pin. Install snap ring with beveled side away from compressor.
2. Install pulley assembly using Pulley Installer (T80L-19703-J) and hammer (if necessary). Install snap ring with beveled side away from
compressor.
3. Install clutch plate shims. Ensure clutch plate aligns with crankshaft key. Install clutch plate using Clutch Plate Installer (T80L-19703-
F).
4. Install crankshaft nut. Using spanner, tighten nut to 10-14 ft. lbs. (13-20 N.m). DO NOT tighten nut with air tools. Using feeler gauge,
check clearance between clutch plate and pulley.
5. Rotate compressor clutch and check clearance in more than one place. Proper clearance is .021-.036" (.53-.91 mm). If clearance is not
correct, add or remove shims.
6. Add same amount new refrigerant oil to compressor as was drained. Rotate compressor 10 revolutions to distribute oil. Install
compressor. Evacuate and recharge system. Perform leak test.
NIPPONDENSO 10P13 SHAFT SEAL
Removal
1. Discharge system using approved refrigerant recovery/recycling equipment and remove compressor. Drain oil from compressor and
record amount for reassembly. Using Clutch Holder (1014), hold clutch plate and remove crankshaft nut.
2. Pull clutch plate from compressor using Clutch Plate Remover (T80L-19703-B). Remove clutch plate shims. Clean compressor area
around seal. Remove felt packing and dust seal retainer from nose of front cover. See Fig. 3
.
3. Using Key Remover (T81P-19623-NH), remove key from compressor shaft. Remove seal seat retaining snap ring. Remove seal seat from
compressor using Seal Seat Remover/Installer (T87P-19623-B).
4. Place Seal Remover/Installer (T87P-19623-C) on compressor. Rotate seal remover/installer clockwise until tangs engage in seal. Pull
seal from compressor.
Installation
1. Lubricate shaft seal, seal seat and inside of compressor nose with refrigerant oil. Install Seal Protector (T71P-19703-H) over compressor
shaft. Using seal remover/installer, install shaft seal in compressor.
2. Rotate seal on compressor shaft to align flat areas on seal with those on compressor shaft.
3. Using seal seat remover/installer, install seal seat until it contacts seal. Install snap ring. Install key in crankshaft with rounded edge
inward.
4. Install clutch plate shims. Ensure clutch plate is aligned with crankshaft key. Using Clutch Plate Installer (T80L-19703-F), install clutch
plate.
5. Install crankshaft nut. Using spanner, tighten nut to 10-14 ft. lbs. (13-20 N.m). DO NOT tighten nut with air tools. Using feeler gauge,
check clearance between clutch plate and pulley.
6. Rotate compressor clutch and check clearance in more than one place. Proper clearance is .021-.036" (.53-.91 mm). If clearance is not
correct, add or remove shims.
7. Add same amount new refrigerant oil to compressor as was drained. Rotate compressor 10 revolutions to distribute oil in compressor.
Install compressor. Evacuate and recharge system. Perform leak test. NOTE:After installing new clutch, cycle clutch 10 tim es with engine at idle speed to prevent clutch slippage.
Page 4 of 7 MITCHELL 1 ARTICLE - GENERAL SERVICING 1991 Ford Compressor Overhaul
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