
F CARLINE 
ITEM 10 
TransmissionRransaxle Service 
The manual  transmission  or transaxle fluid  does not 
require  changing. (Corvette  only.) Change  fluid in over- 
drive  unit every  30,000  miles (50 000  km). 
For  automatic  transmissions  or transaxles,  change 
both the  fluid and filter  every 15,000  miles (25 000  km)  if 
the  car  is  mainly  driven  under  one or more  of these 
conditions: 
@ In  heavy  city  traffic  where  the outside  temperature 
regularly  reaches 90°F (32°C)  or  higher. 
@ In hilly  or mountainous  terrain. 
@ Frequent  trailer  pulling. 
@ Uses such as  found  in taxi,  police  car or delivery 
service. 
If  you  do not  use your  car under any  of these condi- 
tions,  change  both the fluid and filter  every 100,000 miles 
(160  000  km).  See  you Owner's  Manual for further 
details. 
ITEM 11 
Spark  Plug Service* 
Replace  spark  plugs  with  type  listed  in your  Owner's 
Manual. 
ITEM 12 
Spark Plug Wire  Inspection* 
Clean wires  and inspect  for burns, cracks or  other dam- 
age.  Check the wire boot fit  at distributor  and at spark  plugs. 
Replace  wires  as  needed. 
ITEM 13 
Positive Crankcase  Ventilation (PCV) Valve 
Inspection* 
Inspect  valve  for proper function.  Replace  valve if 
necessary  as well  as  any  worn, plugged  or collapsed 
hoses. 
ITEM 14 
EGR  System  Service* 
Conduct  EGR System  Service  as referenced  in  the 
EGR  System  Chart shown  in the appropriate  6E Section. 
Also,  refer to  your GM maintenance  schedule booklet for 
specific  applications. 
ITEM 15 
Air Cleaner  and PCV Filter Replacement* 
On 1.6 and 2.0 liter  engines,  replace  every  50,000 
miles  (80 000  km).  On all other  engines,  replace every 
30,000  miles (50 000  km).  Replace  more  often  under 
dusty conditions.  Ask your dealer for  the proper replace- 
ment  interval  for your  driving  conditions. 
MAINTENANCE  AND LUBRICATION 08-3 
ITEM 16 
Engine  Timing  Check* 
Adjust  timing  to underhood  label specifications.  If 
no  specifications  are  shown, no adjustment  is  needed. 
ITEM 17 
Fuel Tank,  Cap and  Lines Inspection* 
Inspect  fuel  tank, cap and lines (including  fuel  rails 
and  injection  assembly, if so  equipped)  for  damage  or 
leaks.  Inspect  fuel cap gasket  for  an  even  filler neck 
imprint  or any  damage.  Replace  parts  as needed. 
ITEM 18 
Thermostatically  Controlled  Air Cleaner 
Inspection* 
If  your  car is equipped,  inspect all hoses  and ducts 
for  proper  hookup.  Make  sure  valve works  properly. 
OWNER  INSPECTIONS  AND SERVICES 
Listed  below are  inspections  and  services  which 
should  be made  by either  you or a qualified technician  at 
the  intervals  shown to help  ensure proper safety, emission 
performance  and  dependability  of your  car. Take  any 
problems  promptly  to your  dealer  or another  qualified 
technician  for service  advice. Whenever  repairs are neces- 
sary,  have  them  completed  at once.  For  your  safety and 
that  of  others,  any  safety-related  parts  that could  have 
been  damaged  in an  accident should  be inspected  and  all 
needed  repairs should be done  before  operating your  car. 
Be  sure  to use  the proper fluids and lubricants  as shown in 
Figure  OB-2. 
WHILE  OPERATING YOUR  VEHICLE 
Automatic transmissionltransaxle  shift indi- 
cator operation - Make sure the indicator points  to the 
gear  chosen. 
Horn operation - Blow  the horn  occasionally to 
make  sure it works.  Check  all  button locations. 
I 
Brake system  operation -- Be alert  to abnormal 
sounds,  increased  brake pedal travel  or repeated  pulling to 
one  side  when  braking.  Also, if a brake  warning  light 
comes  on or  flashes,  or the  anti-lock  warning light  (if 
equipped)  comes  on or remains  on, something  may be 
wrong with  part of the  brake  system.  Have it inspected and 
repaired  at  once. 
Exhaust  system  operation - Be alert  to  any 
changes  in the  sound  of the system  or any smell  of fumes. 
These  are signs  the system may  be leaking  or overheating. 
. 
Have  it inspected  and repaired  at  once. Also see "Engine 
Exhaust  Gas Caution (Carbon Monoxide)" and  "Catalytic 
Converter"  in your  Owner's  Manual. 
*An Emission  Control Service   

ENGINE GENERAL  INFORMATION 6-1 
SECTION 6 
NE GENERAL NFORMAT 
Description ............................................................... 6 TBI ...................................... .. ...... 6E2 ................ Engine  Mechanical  Multi Port Fuel Injection  (MPFI)  6E3 - 
............................................... 2.8L V-6 ....................................................... 6A2 Exhaust  Systems  6F 
5.OL V-8 ......................................................... 6A3 ~~~~~~l ~~f~~~~ti~~ ..................................... 6-2 
............................ Engine  Cooling ...................................................... 6B Engine  Performance  Diagnosis  6-3 ............................. Engine  Fuel  6C Engine  Mechanical  Diagnosis 
6-3 ........................................................... ................................... Engine Knock Diagnosis  6-4 
Engine  Electrical ................................................... 6D Compression Test ...................................... ... 6-5 
................... Driveability and Emission Controls ...................... 6E Oil  Leak  Detection .. ..................... 6-5 
ALL  NEW  GENERAL  MOTORS VEHICLES  ARE CERTIFIED  BY THE  UNITED  STATES 
ENVIRONMENTAL  PROTECTION AGENCY AS CONFORMING  TO THE  REQUIREMENTS  OF 
THE REGULATIONS  FOR THE CONTROL  OF AIR  POLLUTION  FROM NEW MOTOR  VEHICLES. 
THlS CERTIFICATION  IS  CONTINGENT  ON CERTAIN  ADJUSTMENTS  BEING  SET TO 
FACTORY  STANDARDS.  IN MOST  CASES,  THESE  ADJUSTMENT POINTS EITHER HAVE 
BEEN  PERMANENTLY  SEALED AND/OR  MADE INACCESSIBLE  TO  PREVENT 
INDISCRIMINATE  OR ROUTINE  ADJUSTMENT  IN THE  FIELD.  FOR 
THlS REASON,  THE 
FACTORY  PROCEDURE  FOR TEMPORARILY  REMOVING PLUGS,  CAPS,  ETC., FOR 
PURPOSES  OF SERVICING  THE PRODUCT  MUST BE STRICTLY  FOLLOWED  AND, 
WHEREVER  PRACTICABLE,  RETURNED TO THE ORIGINAL INTENT  OF THE  DESIGN. 
DESCRIPTION OF: SECTION 6 
SECTION  6A - ENGINE MECHANICAL used for  each  carburetor.  TBI units  are described  in 
This  section general  contains information  on  the Section 6E. 
mechanical  parts of the  engine,  such  as  block, 
crankshaft,  pistons, valve train,  and camshaft,  that are 
common  to most  engines.  Overhaul  procedures, 
removal  and replacement  procedures,  and 
s~ecifications are also  covered.  Subsections  furnish 
detailed  information  on each  specific engine.  Service 
SECTION 6D - ENG l N E ELECTRICAL 
information  is  also  given that relates  to that  engine's 
use  in  each 
Carline. Specific  subsections  are:  Items 
covered  in this  section  are battery, 
generator,  starter, primary  and secondary  ignition, 
6A2 
- 2.8L V-6  Engine 
engine  wire  harness, spark plugs and wires,  and 
6A3 
- 5.OL V-8  Engine 
ignition  switch. 
SECTION 6B - ENGINE COOLING 
Engine  cooling  system  components such  as 
radiator,  water pump,  thermostat, and cooling fan,  are 
covered  in this  section.  Accessory  drive  belts  are also 
covered,  along with  cooling  system capacities. 
SECTION 6C - FUEL  SYSTEM 
This section  contains information  on all the  parts 
of  the  fuel  system 
except the carburetor,  or Throttle 
Body Injection  unit (TBI) itself. Items  covered  are fuel 
tank,  fuel pump,  and fuel lines.  Specific  subsections  are 
SECTION 6E - DRIVEABILITY AND EMISSIONS 
This section  covers  emission  control systems 
general information,  and diagnostic  procedures  which 
will  lead  to repairing  performance  and driveability 
related problems for gasoline engine equipped  vehicles. 
All  emission  components  are covered,  as well  as all 
removal  and replacement  procedures.  Instructions on 
use  of special tools  are also  given. Specific  sections are: 
6E 
- Driveability  and Emissions 
6E2 
- Fuel  Injection  (TBI)   

6-2 ENGINE GENERAL  INFORMATION 
6E3 - Fuel  Injection  (Ported)  This  section  has  information 
on all  exhaust 
system  parts,  such  as  tailpipes,  mufflers, and the 
SECTION 6F - EXHAUST  SYSTEM catalytic  converter. 
GENERAL INFORMAflION 
CLEANLINESS  AND CARE 
An  automobile engine  is a combination  of many 
machined,  honed,  polished  and lapped  surfaces  with 
tolerances  that are measured  in the  ten-thousandths  of 
an  inch.  When  any  internal engine parts  are  serviced, 
care  and cleanliness  are important. A  liberal coating  of 
engine  oil  should  be  applied  to friction  areas  during 
assembly,  to protect  and  lubricate the surfaces  on 
initial operation.  Throughout this section, it should be 
understood  that proper  cleaning  and  protection  of 
machined  surfaces  and friction  areas is part  of the 
repair  procedure.  This is  considered  standard  shop 
practice,  even if not  specifically  stated.  PREVENTING 
DAMAGE AND IN 
CONTRIBUTING  TO RELIABLE  ENGINE 
PERFORMANCE. 
When  raising  or supporting  the engine  for  any 
reason,  do not  use a jack  under  the oil pan.  Due to the 
small clearance  between the oil pan  and the oil pump 
screen, jacking  against  the oil pan  may  cause  it to  be 
bent  against  the pump  screen  resulting  in a damaged 
oil  pick-up unit. 
When working  on the  engine,  remember  that the 
12-volt  electrical  system is  capable  of causing  short 
circuits.  When  performing  any  work  where electrical  terminals could  possibly be grounded,  the ground cable 
of  the  battery  should  be disconnected  at the battery. 
Any  time  the  carburetor  or air  cleaner  is 
train components are removed removed,  the intake  opening  should  be  covered.  This for service, they should be in order' will protect against entrance of foreign be installed  in  the same locations,  and with  the same material, which could follow the intake passage into mating  surfaces,  as when  removed 
the cylinder  and  cause  extensive damage when the - 
Battery  cables should  be disconnected  before any engin; is started. 
major  work is performed  on  the engine.  Failure  to  IN THE  MECHANICAL  PROCEDURES 
disconnect cables  may result  in damage  to wire harness  DESCRIBED IN THIS  SECTION,  GENERALLY 
or  other  electrical parts.  NO 
REFERENCES  WILL BE MADE  TO THE 
REMOVAL  OF OPTIONAL  EQUIPMENT  SUCH 
ENGINE SERVICE AS POWER  STEERING  PUMP, AIR 
CONDITIONING  COMPRESSOR, ETC. 
THE  FOLLOWING  INFORMATION  ON SHOULD IT BECOME  NECESSARY  TO 
ENGINE  SERVICE  SHOULD BE NOTED  REMOVE ANY  SUCH  ITEM TO 
PERFORM 
CAREFULLY,  AS IT IS IMPORTANT  IN OTHER  SERVICE, REFER TO THE 
APPROPRIATE  SECTION OF THIS  SERVICE 
MANUAL FOR SPECIFIC INFORMATION. 
ENGINE  PERFORMANCE DIAGNOSIS 
INTRODUCTION interchangeably for so long,  it was  necessary  to decide 
on  the  most  common  usage and then  define them. If the 
Engine Performance procedures are definition  is not understood,  and the exact Symptom  is 
guides  that will lead to the most  probable  causes of not used, the Diagnostic procedure will not work. engine  performance  complaints.  They  cover  the 
components  of the  fuel,  ignition,  and  mechanical  It 
is important  to keep  two facts  in mind: 
systems  that could  cause  a  particular 
complaint, and 1. The procedures are written  to diagnose problems 
then  outline  repairs  in a logical  sequence.  on cars 
that have 
"run  well at one  time" and 
that  time  and wear  have created  the condition. 
It  is important  to determine  if the 
"Service ~~~i~~ soon- light is "ON,~' or has come for 2. All  possible  causes cannot  be covered, 
a short  interval  while driving. If  the 
"Service  Engine particularly  with  regard  to emission  controls.  If 
Soon" light has come "ON," the Computer  doing the work  prescribed  does  not  correct  the 
Command  Control  System or DECS  should  be  complaint,  then either  the wrong  Symptom  was 
checked  for stored 
"Trouble  Codes" (See Diagnostic  used, or a more  detailed analysis  will have  to be 
Circuit  Check,  Section  6E,  for the  engine  you are  made. 
working  on) which  may  indicate  the cause  for  the  All of the  Symptoms can  be caused  by worn  out 
performance 
complaint.Each Symptom is  defined, and  or  defective parts such as Spark  Plugs,  Ignition 
it  is  important  that the correct  one  be selected,  based  Wiring, etc. If time  and/or  mileage  indicate  that 
on  the  complaints reported  or found.  The definition  of  parts should  be replaced, it is recommended  that 
each  symptom is included with  the symptom.  it 
be  done. 
The  words  used may not be what  you are used  to  Refer  to: 
in  all  cases,  but because  these terms  have been  used 
@ Section 6E - Driveability  and Emissions   

4. Remove bearing cap. The flattened  gaging plastic 
will  be  found adhering  to either  the bearing  shell 
or journal. 
5.  On the edge  of gaging plastic  envelope,  there is a 
graduated  scale  which  is correlated  in 
thousandths  of a millimetre.  Without removing 
the  gaging plastic,  measure its compressed  width 
(at  the  widest  point) with the graduations  on the 
gaging plastic  envelope.  Normally, main  bearing 
journals  wear evenly  and are not  out-of-round. 
However,  if 
a bearing  is being  fitted to an 
out-of-round (.025mm max.),  be sure  to fit  to the 
maximum  diameter of the  journal:  If  the bearing 
is  fitted  to the  minimum diameter  and the journal 
is  out-of-round 
.025mm, interference  between the 
bearing  and  journal  will result  in  rapid  bearing 
failure.  If  the flattened  gaging plastic  tapers 
toward  the middle  or ends,  there is a difference 
in  clearance indicating  taper,  low spot  or other 
irregularity  of the  bearing  or journal.  Be sure  to 
measure  the journal  with a  micrometer  if the 
flattened  gaging  plastic  indicates  more than 
,025mm difference. 
6.  If the  bearing  clearance  is within  specifications, 
the  bearing  insert  is satisfactory.  If the  clearance 
is  not  within  specifications,  replace  the insert. 
Always  replace  both  upper  and  lower  inserts as 
a  unit. 
7.  A standard, 
.016mm and .032mm undersize 
bearing may  produce the proper clearance.  If not, 
it  will  be  necessary  to regrind  the crankshaft 
journal  for use  with  the next  undersize  bearing. 
After  selecting  new bearing,  recheck  clearance. 
8. Proceed  to the  next  bearing.  After all  bearings 
have  been  checked  rotate the crankshaft  to see 
that  there  is no  excessive  drag. 
9.  Measure crankshaft  end  play (see specifications) 
by  forcing  the crankshaft  to  the extreme  front 
position.  Measure at the  front  end of the 
#3 main 
bearing  with  a feeler  gage (Figure  6A2-25). 
10.  Install  a  new rear main  bearing  oil seal  in the 
cylinder  block and main  bearing  cap. 
Figure 6A2-25 Measuring Crankshaft  End Play 
Replacement 
Main bearings  may  be replaced  with or without 
removing  the crankshaft. 
With  Crankshaft  Removal 
1. Remove and inspect  the crankshaft. 
2.  Remove  the main  bearings  from  the cylinder 
block  and main  bearing  caps. 
3.  Coat  bearing  surfaces  of new,  correct  size,  main 
bearings  with  oil and  install  in the  cylinder  block 
and  main  bearing  caps. 
4. Install  the crankshaft. 
Without  Crankshaft  Removal 
With oil pan,  oil pump  and spark  plugs removed, 
remove  cap on  main  bearing  requiring 
replacement  and remove  bearing  from  cap. 
Install  a main  bearing  removing  and installing 
tool  in  oil  hole  in crankshaft  journal.  If such  a 
tool  is not  available,  a cotter  pin  may  be  bent  as 
required  to do  the  job. 
Rotate the  crankshaft clockwise as viewed  from 
the  front  of engine.  This will roll  upper  bearing 
out  of block. 
Oil  new  selected  size  upper bearing  and insert 
plain  (unnotched)  end  between  crankshaft and 
indented  or notched  side  of block.  Rotate  the 
bearing  into place  and remove  tool  from oil  hole 
in  crankshaft journal.  Inspect for  burrs at oil hole, 
remove  if required. 
Oil  new  lower bearing  and install  in bearing  cap. 
Install  main  bearing  cap with  arrows  pointing 
toward  front of engine. 
Torque  all main  bearing  caps,  EXCEPT THE 
#3 MAIN CAP, to 95 N.m (70  lb. ft.).  Torque 
# 3 main bearing  cap to 15 N m (1 1 lb.  ft.)  then 
tap  end  of crankshaft,  first rearward then forward 
with  a lead  hammer. This  will line up rear  main 
bearing  and crankshaft  thrust surfaces. 
Retorque 
all main  bearing  caps to 95 N.m (70  Ib. ft.). 
1 /DUST LIP 
Figure 6A2-26 Removing  Seal   

6A2-26 2.8 LITER V-6 
2. Remove  the spark  plugs. Installation 
3. Remove 
crankshaft  pulley and torsional  damper. 1. Install rear main bearing  oil seal  in cylinder  block 
4.  Remove  oil pan  and oil pump.  and 
rear  bearing  cap grooves. 
5. Remove  water  pump,  crankcase  front cover, 2. Lubricate  seal with  engine  oil.  Keep oil off 
camshaft  sprocket  and  timing chain.  parting 
line  surface. 
3.  Install  main  bearings  in cylinder  block  and main 
6.  Check  the connecting  rod  caps for cylinder 
bearing  caps then  lubricate  bearing surface with 
number  identification.  If  necessary  mark them. 
engine oil. 
7.  Remove  the connecting  rod  caps and 
push the 
4. 1n;tall crankshaft,  being  careful  not to damage 
pistons  to top  of bores. 
bearing  surfaces. 
8.  Remove  main bearing caps  and lift crankshaft out  5. Recheck  bearing  clearances  using  plastigage. 
of  cylinder  block.  6. 
Apply a thin coat  of anaerobic  sealant 
# 1052357 
9.  Remove  rear 
main  bearing  oil  seal  and main  or 
equivalent  to rear  of the  block  mating surface 
bearings  from cylinder  block  and  main bearing  or  corresponding 
surface or rear  main  cap only. 
caps.  Do 
not  allow  sealer  on  crankshaft  or seal. 
7.  Install  main  bearing  caps with  arrow  pointing 
Cleaning and  Inspection toward front of engine. 
8.  Torque  all  except 
#3 main  bearing  cap bolts  to 
1.  Wash  crankshaft  in  solvent  and dry with 
specifications.  Torque 
#3 main bearing cap bolts 
compressed  air.  to 14-16 
N-m (10-12  lbs.  ft.)  then tap end  of 
2.  Measure 
dimensions  of main bearing  journals and  crankshaft, first rearward  then  forward  with  a 
crankpins  with a  micrometer  for out-of-round,  lead 
hammer. This  will line up rear  main bearing 
taper  or undersize  (See Specifications).  and crankshaft 
thrust surfaces. 
Retorque all main 
3.  Check 
crankshaft  for run-out  by supporting  at bearing 
cap bolts  to specifications. 
the front and rear main bearings journals in "V" 9.  Measure  crankshaft 
end  play with  a feeler  gage. 
blocks  and check  at  the  front and rear  Force crankshaft forward and measure clearance 
intermediate journals  with a dial  indicator  (See  between the  front  of the 
#3 main  bearing  and 
Specifications).  crankshaft thrust surface. 
4. Replace  or recondition  the crankshaft  if out  of  10. 
Install  flywheel  and torque to  specifications. 
specifications. 
SPROCKET  OR GEAR  REPLACEMENT 
Remove  crankshaft  sprocket  using Tool J-5825, 
install  using  Tool J-5590. 
GENERAL DATA 
TYPE .................................................................................................................................... 60" V-6 
DISPLACEMENT 
............................................................................................................. 2.8  Liter 
RPO 
........................................................................................................................................... LB8 
BORE ......................................................................................................................................... 89 
STROKE 
................................... .... ............................................................................................... 76 
COMPRESSION  RATIO 
....................................................................................................... 8.9: 1 
FIRING  ORDER 
.......................................................................................................... 1-2-3-4-5-6 
Cylinder  Bore 
DIAMETER .............................................................................................................. 88.992-88.070 
OUT  OF ROUND 
............................................................................................................. .02 Max. 
TAPER-THRUST  SIDE 
................................................................................................. .02 Max. 
Piston 
CLEARANCE .................................................................................................................. .O 17-,043 
Piston  Ring   

BA3-22 V-8 ENGINE 
5. On the  edge  of gaging plastic  envelope  there is a 
graduated  scale  which  is correlated  in 
thousandths  of an  inch.  Without  removing the 
gaging  plastic, measure  its compressed width  (at 
the  widest  point)  with  the  graduations  on the 
gaging  plastic envelope  (fig.  6A3-40). 
Normally  main bearing journals  wear  evenly and 
are  not  out-of-round.  However,  if a bearing  is 
being  fitted to  an  out-of-round  journal 
(.00lU 
max.),  be sure to  fit to the  maximum diameter  of 
the  journal:  If the  bearing  is fitted  to the 
minimum  diameter and the journal  is 
out-of-round 
.001", interference  between the 
bearing  and journal  will result  in rapid  bearing 
failure.  If  the flattened  gaging plastic  tapers 
toward  the middle  or ends,  there is a difference 
in  clearance  indicating  taper, low spot  or other 
irregularity  of the  bearing  or journal.  Be sure  to 
measure  the journal  with  a  micrometer  if the 
flattened  gaging plastic indicates more  than 
.00lV 
difference. 
6. If the  bearing  clearance  is within  specifications, 
the  bearing  insert  is satisfactory.  If the  clearance' 
is  not  within  specifications,  replace  the insert. 
Always  replace  both  upper  and lower  inserts  as 
a  unit.  
If  a new  bearing  cap is being  installed  and 
clearance  is less  than 
.00 1 ", inspect  for burrs  or 
nicks;  if none  are found  then  install  shims as 
required. 
I MEASURE END PLAY 
Fig. 6A3-4 1 Measuring  Crankshaft  End Play - Typical 
7. A standard, .001" or .002" undersize bearing  may 
produce  the  proper  clearance.  If  not,  it  will be 
necessary  to regrind  the crankshaft  journal  for 
use  with  the next  undersize  bearing. 
After  selecting  new bearing,  recheck  clearance. 
8. Proceed  to the  next  bearing.  After all  bearings 
have  been  checked  rotate  the  crankshaft  to see 
that  there  is no  excessive  drag. 
When  checking 
&t 1  main  bearing,  loosen 
accessory  drive belts  so  as  to prevent  tapered 
reading  with  plastic  gage. 
9. Measure crankshaft  end  play (see specifications) 
by  forcing  the  crankshaft  to the  extreme  front 
position.  Measure  at  the  front end of the  rear 
main  bearing  with  a  feeler  gage  (fig. 
61\3-41), 
10. Install  a  new rear main  bearing  oil  seal in the 
cylinder  block and main  bearing  cap. 
Replacement 
Main bearings  may  be replaced  with  or without 
removing  the  crankshaft. 
NOTICE: Some production  engines may  come 
with  rear main bearings with  the distance  between 
thrust  faces 
,008" wider than  the  standard  size. 
The  crankshaft  will be identified  by 
,008" stamped 
on  the  rear  counterweight.  If the  rear  main 
bearings  are replaced,  they  must have the  proper 
distance  between  thrust faces to ensure  correct 
crankshaft end  play. 
With Crankshaft  Removal 
1. Remove  and inspect  the  crankshaft. 
2. Remove  the main  bearings  from the cylinder 
block  and main  bearing  caps. 
3. Coat  bearing  surfaces  of new,  correct  size, main 
bearings with oil  and install in  the cylinder block 
and  main  bearing  caps. 
4.  Install the  crankshaft. 
Without  Crankshaft  Removal 
1. With oil pan, oil  pump and spark  plugs removed, 
remove  cap on  main  bearing  requiring 
replacement  and remove bearing  from cap. 
2.  Install  a 
main  bearing  removing  and  installing 
tool  in oil  hole  in crankshaft  journal. If such  a 
tool  is not  available,  a  cotter pin may  be bent  as 
required  to do  the  job. 
3. Rotate  the  crankshaft  clockwise as viewed  from 
the  front  of engine.  This will roll  upper  bearing 
out  of block. 
4.  Oil new  selected  size upper  bearing  and insert 
plain  (unnotched)  end  between  crankshaft  and 
indented  or notched  side  of block. 
Rot$e the  bearing  into place  and remove tool from  oil 
hole  in crankshaft  journal. 
5. Oil new  lower  bearing  and install  in bearing cap. 
6. Install  main  bearing  cap with  arrows  pointing 
toward  front  of engine. 
7. Torque  all main  bearing  caps,  EXCEPT THE 
REAR  MAIN CAP, to specifications.  Torque 
rear  main bearing  cap to 10-  12 lb.  ft. (14- 
16N. m) 
then  tap end  of crankshaft,  first  rearward  then 
forward  with  a lead  hammer.  This  will line  up 
rear  main  bearing  and crankshaft  thrust surfaces. 
Retorque all main  bearing caps  to specifications. 
REAR MAIN SEAL 
Removal 
1. Remove transmission  as outlined  in  Section 7. 
2. Using notches  provided 
in retainer,  pry out seal 
with  a screwdriver  (Figure 6A4-43).   

6A3-28 V-8 ENGINE 
16. Install 
radiator  and fan shroud  and reconnect 
radiator and  heater hoses. 
17.  Fill  cooling system. 
18.  Fill 
crankcase  with  oil. See owner's  manual  for 
specifications. 
19.  Install  air  cleaner. 
20.  Install  hood. 
21.  Connect  battery cables. 
NOTICE: To avoid  possible  arcing of battery, 
connect  positive battery  cable first. 
22.  Start  engine, check for  leaks  and check  timing. 
CRANKSHAFT 
The  crankshaft can  be removed while  the engine 
is disassembled  for overhaul, as previously outlined,  or 
without  complete  disassembly. 
Removal 
With the  engine removed  from the vehicle and the 
transmission  and/or clutch housing  removed 
from  the engine,  mount engine  in  stand and 
clamp  securely. 
Remove  the oil dip  stick  and oil dip  stick  tube,  (if 
applicable).  
Remove  the starting  motor,  clutch  assembly (if 
equipped)  and flywheel. 
Remove  the spark  plugs. 
Remove  crankshaft  pulley and torsional damper. 
Remove  oil pan  and oil pump. 
Remove  crankcase  front cover,  and if so 
equipped,  remove  timing  chain  and camshaft 
sprocket. 
Check  the connecting  rod caps  for cylinder 
number  identification.  If  necessary,  mark them. 
Remove  the connecting  rod caps  and push  the 
pistons  to top  of bores. 
Remove main bearing caps  and lift crankshaft  out 
of  cylinder  block. 
Remove  rear main  bearing  oil  seal  and main 
bearings  from cylinder  block  and  main bearing 
caps. 
Cleaning  and Inspection 
1. Wash  crankshaft  in  solvent and dry with 
compressed  air. 
2.  Measure  dimensions  of main bearing  journals and 
crankpins  with a  micrometer  for out-of-round, 
taper  or undersize.  (See Specifications.)  3. 
Check  crankshaft  for  run-out  by supporting  at 
the front and rear  main  bearings journals in 
"V" 
blocks and check  at the  front  and  rear 
intermediate journals  with a dial  indicator.  (See 
Specifications.) 
4. Replace  or recondition  the  crankshaft if out  of 
specifications. 
SPROCKET  OR GEAR REPLACEMENT 
e Remove crankshaft  sprocket using Tool 
5-5825, install  using  Tool J-5590. 
Installation 
1. 
Install rear  main bearing oil seal  in cylinder block 
and  rear  main  bearing  cap grooves.  Install with 
lip  of seal  toward  front of engine. Where seal  has 
two  lips  install  lip  with  helix towards  front  of 
engine. 
2.  Lubricate  lips of seal with engine oil.  Keep oil off 
parting  line surface. 
3.  Install  main  bearings in cylinder  block and main 
bearing  caps  then lubricate  bearing  surface with 
engine oil. 
4.  Install  crankshaft,  being careful  not  to damage 
bearing  surfaces. 
5.  Recheck  bearing  clearances  using plastigage. 
6.  Apply  a thin  coat  of brush-on  type  oil  sealing 
compound  to block  mating  surface  and 
corresponding  surface of cap  only.  Do not  allow 
sealant  on  crankshaft  or seal. 
7.  Install  main  bearing  caps  with  arrows pointing 
toward  front  of engine. 
8.  Torque  all except  rear main  bearing  cap bolts  to 
specifications.  Torque rear main bearing  cap bolts 
to  10-12  lbs.  ft. (14-16 
N.m)then tap  end  of 
crankshaft,  first rearward  then  forward  with a 
lead  hammer.  This will line up rear  main bearing 
and  crankshaft  thrust surfaces. 
Retorque all main 
bearing  cap bolts  to specifications. 
9.  Measure  crankshaft  end  play with  a feeler  gage. 
Force crankshaft forward  and measure clearance 
between  the front  of the  rear  main bearing  and the 
crankshaft  thrust surface. 
10.  Install  flywheel  and torque  to  specifications.  A 
wood  block  placed between  the  crankshaft  and 
cylinder  block  will  prevent crankshaft  from 
rotating. 
Align  dowel  hole  in  flywheel with  dowel 
hole  in  crankshaft.  On vehicles  equipped 
with  automatic  transmissions,  install 
flywheel  with the converter  attaching pads 
towards  transmission. 
GENERAL DATA 
TYPE .................................................................................................................................. 90" V-8 
DISPLACEMENT 
............................................................................... 305  Cu.  In., 350 Cu.  In. 
......................................................... LITER  (VIN) ................................... ...... 5.0, (E), (F), 5.7  (8) 
RPO ......................................................................................................................... L03, LB9, L98 
BORE ........................................................................................................................ 3.736, 4.000 
STROKE 
........................... .. ....................................................................................... 3.480,  3.480 
COMPRESSION  RATIO 
................................................................................... 931, 931, 9.5:1 
FIRING ORDER .................................................................................................... 1-8-4-3-6-5-7-2   

ENGINE FUEL BC-1 
SECTION 6C 
NE FUEL 
CONTENTS 
General Description ..................................... 6C-1 Fuel 
Cap ........................................................... 6C-3 
.................................................. ............................................. Alcohol-In-Fuel  6C- 1 Fuel Filter Neck  6C-3 
................... ............ Fuel Metering .................................................. 6C-2  Fuel Gage  Sending Unit .. 6C-4 
....................... ............................... Throttle  Body Injection  (TBI) .... 6C-2 Diagnosis ,. 6C-4 ................... Service 
Procedures ............................................. 6C-4 
Port  Fuel  Injection ...................................... 6C-2 
Pressure Relief ........................................... 6C-4 
Fuel  Feed  and Return  Pipe 
............................... 6C-2 
Flow Test .................................................... 6C-4 
Fuel  Pipes  (MPFI) 
.......................................... 6C-3 
Pressure Test - TBI ................................... 6C-4 
Fuel  and Vapor  Hoses 
....................................... 6C-3 
Pressure Test - MPFI .................................... 6C-4 
Fuel  Pump ........................................................ 6C-3 ...................................................... Fuel Pump  Relay .............................................. 6C-3  Fuel Tank  6C-4 
Fuel  Filter 
......................................................... 6C-3  Accelerator  Controls ...................................... 6C-5 
Fuel  Tank 
....................................................... 6C-3 
All new  General Motors vehicles are  certified by 
the  United States  Environmental  Protection Agency as 
conforming  to the  requirements  of the  regulations  for 
the  control  of air  pollution  from new motor  vehicles. 
This  certification  is contingent  on certain adjustments 
being  set to factory  standards.  In most  cases,  these 
adjustment  points  either  have been permanently 
sealed  and/or  made  inaccessible to prevent 
indiscriminate  or routine adjustment  in the  field.  For 
this  reason,  the factory  procedure  for temporarily 
removing  plugs, caps, etc., for purposes  of servicing  the 
product  must be strictly  followed  and, wherever 
practicable,  returned to the  original  intent of the 
design. 
GENERAL DESCRIPTION 
All  gasoline  engines  are designed  to use  only 
unleaded  gasoline. Unleaded  gasoline  must be used  for 
proper  emission  control system operation.  Its use  will 
also minimize  spark plug fouling  and extend engine  oil 
life.  Using  leaded  gasoline can damage  the emission 
control  system and could  result  in  loss  of emission 
warranty  coverage. 
All  cars  are equipped  with  an Evaporative 
Emission  System.  The purpose  of the  system  is  to 
minimize  the escape  of fuel  vapors  to the  atmosphere. 
Information  on  this  system will  be  found in  Section 
6E2, or 6E3. 
When  working  on the  fuel  system,  there are 
several things  to keep in  mind. 
@ Any time  fuel system  is being  worked  on, 
disconnect  the negative  battery cable 
except  for those  tests where  battery 
Adhere to all  Notices  and Cautions. 
Always  keep a  dry  chemical  (Class  B) fire 
extinguisher  near  the work  area. 
- 
Always  use a backup  wrench  when loosening  or 
tightening  a screw couple fitting. 
The  torque  on a screw fitting  is 
30 N-m (22  lb. 
ft.). 
Pipe  is  used on  all  MPFI,  TPI, SFI, and TBI 
applications.  Fittings require the use  of an 
"0" 
Ring.  Replace all pipe with  the same  type of pipe 
and  fittings  that were removed. 
All  fuel  pipes  must meet GM Specification 
124-M,  or its  equivalent. 
All  fuel  hoses  must meet GM Specification 
6163-M,  or its  equivalent. 
Do  not  replace fuel pipe with  fuel  hose. 
voltage is required. 
@ On MPFI,  TPI, SF1 and TBI  systems,  always A1cohol-ln-Fuel 
relieve the line pressure before servicing any  fuel Certain driveability  complaints  such  as 
system components.  hesitation,  lack of power,  stall,  no start,  etc.,  may  be 
@ Do not  repair  the fuel  system  until you have read  caused 
by an excessive  amount of alcohol-in-fuel.  The 
the  copy  and checked  the illustrations  relating to complaints 
may be due  to fuel  system  corrosion  and 
that  repair.  subsequent 
fuel filter plugging,  deterioration of rubber