| NATEF Tasks |
Description |
Priority Designation |
| A |
General Engine Diagnosis; Removal and Reinstallation
(R & R) |
|
| I.A.1 |
Identify and interpret engine concern; determine
necessary action. |
P-1 |
| I.A.2 |
Research applicable vehicle and service information,
such as internal engine operation, vehicle service history, service
precautions, and technical service bulletins |
P-1 |
| I.A.3 |
Locate and interpret vehicle and major component
identification numbers (VIN, vehicle certification labels, and calibration
decals). |
P-1 |
| I.A.4 |
Inspect engine assembly for fuel, oil, coolant,
and other leaks; determine necessary action. |
P-1 |
| I.A.5 |
Diagnose engine noises and vibrations; determine
necessary action. |
P-2 |
| I.A.6 |
Diagnose the cause of excessive oil consumption,
unusual engine exhaust color, odor and sound; determine necessary
action. |
P-2 |
| I.A.7 |
Perform engine vacuum test; determine necessary
action. |
P-1 |
| I.A.8 |
Perform cylinder power balance tests determine
necessary action. |
P-1 |
| I.A.9 |
Perform cylinder compression test; determine necessary
action. |
P-1 |
| I.A.10 |
Perform cylinder leakage test; determine necessary
action. |
P-1 |
| I.A.11 |
Remove and reinstall in a late model front-wheel
drive vehicle (OBDI or newer); reconnect all attaching
components and restore the vehicle to running condition. |
P-1 |
| I.A.12 |
Remove and reinstall in a late model rear-wheel
drive vehicle (OBDI or newer); reconnect all attaching
components and restore the vehicle to running condition. |
P-3 |
| B |
Cylinder Head and Valve Train Diagnosis
and Repair |
|
| I.B.1 |
Remove cylinder head (s); visually inspect cylinder
head (s) for cracks; check gasket surface areas for warpage and
leakage; check passage condition. |
P-2 |
| I.B.2 |
Install cylinder heads and gaskets; tighten according
to manufacturer's specifications and procedures. |
P-1 |
| I.B.3 |
Inspect valve springs for squareness and free height
comparison; determine necessary action. |
P-2 |
| I.B.4 |
Replace valve stem seals on an assembled engine;
inspect valve spring retainers, locks, and valve grooves; determine
necessary action. |
P-2 |
| I.B.5 |
Inspect valve guides for wear for wear; check valve
stem-to-guide clearance; determine necessary action. |
P-3 |
| I.B.6 |
Inspect valves and valve seats; determine necessary
action. |
P-3 |
| I.B.7 |
Check valve face-to-seat contact and valve seat
concentricity (runout); determine necessary action. |
P-3 |
| I.B.8 |
Check valve spring assembled height and valve stem
height; determine necessary action.. |
P-3 |
| I.B.9 |
Inspect pushrods, rocker arms, rocker arm pivots
and shafts for wear, bending, cracks looseness, and blocked oil
passages (orifices); determine necessary action. |
P-2 |
| I.B.10 |
Inspect hydraulic or mechanical lifters; determine
necessary action. |
P-2 |
| I.B.11 |
Adjust valves (mechanical or hydraulic lifters). |
P-1 |
| I.B.12 |
Inspect camshaft drives (including gear wear and
backlash, sprocket and chain wear); determine necessary action. |
P-2 |
| I.B.13 |
Inspect and replace timing belts (chains), overhead
camdrive sprockets, and tensioners; check belt/chain tension; adjust
as necessary. |
P-1 |
| I.B.14 |
Inspect camshaft for runout, journal wear and lobe
wear. |
P-2 |
| I.B.15 |
Inspect camshaft bearing surface for wear, damage,
out-of-round, and alignment; determine necessary action. |
P-3 |
| I.B.16 |
Establish camshaft(s) timing and cam sensor indexing
according to manufacturer's specifications and procedures. |
P-1 |
| C |
Engine Block Assembly Diagnosis and Repair |
|
| I.C.1 |
Disassemble engine block; clean and prepare components
for inspection and reassembly. |
P-2 |
| I.C.2 |
Inspect engine block for visible cracks, passage
condition, core and gallery plug condition, and surface warpage;
determine necessary action. |
P-2 |
| I.C.3 |
Inspect internal and external threads; restore
as needed includes installing thread inserts). |
P-2 |
| I.C.4 |
Inspect and measure cylinder walls for damage,
wear, and ridges; determine necessary action. |
P-2 |
| I.C.5 |
Deglaze and clean cylinder walls. |
P-2 |
| I.C.6 |
Inspect and measure camshaft bearings for wear,
damage, out-of-round, and alignment; determine necessary action. |
P-3 |
| I.C.7 |
Inspect crankshaft for end play, straightness,
journal damage, keyway damage, thrust flange and sealing surface
condition, and visual surface cracks; check oil passage condition;
measure journal wear; check crankshaft sensor reluctor ring (where
applicable); determine necessary action. |
P-2 |
| I.C.8 |
Inspect and measure main and connecting rod bearings
for damage, clearance, and end play; determine necessary action
(includes the proper selection of bearings). |
P-2 |
| I.C.9 |
Identify piston and bearing wear patterns that
indicate connecting rod alignment and main bearing bore problems;
inspect rod alignment and bearing bore condition. |
P-3 |
| I.C.10 |
Inspect and measure pistons and pins; determine
necessary action. |
P-2 |
| I.C.11 |
Remove and replace piston pin. |
P-3 |
| I.C.12 |
Inspect, measure, and install piston rings. |
P-1 |
| I.C.13 |
Inspect auxiliary (balance, intermediate, idler,
counterbalance or silencer) shaft(s); inspect shaft (s) and support
bearings for damage and wear; determine necessary action; reinstall
and time. |
P-2 |
| I.C.14 |
Inspect or replace crankshaft vibration damper
(harmonic balancer). |
P-3 |
| I.C.15 |
Assemble the engine using gaskets, seals, and formed-in-place
(tube applied) sealants, thread sealers, etc. according to manufacturer's
specifications. |
P-2 |
| D |
Lubrication and Cooling Systems Diagnosis
and Repair |
|
| I.D.1 |
Perform oil pressure tests; determine necessary
action. |
P-1 |
| I.D.2 |
Inspect oil pump gears or rotors, housing, pressure
relief devices, and pumpdrive; perform necessary action. |
P-2 |
| I.D.3 |
Perform cooling system, cap, and recovery system
tests (pressure, combustion leakage, and temperature); determine
necessary action. |
P-1 |
| I.D.4 |
Inspect, replace, and adjust drive belts, tensioners,
and pulleys; check pulley and belt alignment. |
P-1 |
| I.D.5 |
Inspect and replace engine cooling and heater system
hoses. |
P-1 |
| I.D.6 |
Inspect, test, and replace thermostat and housing. |
P-2 |
| I.D.7 |
Test coolant; drain and recover coolant; flush
and refill cooling system with recommended coolant; bleed air as
required. |
P-1 |
| I.D.8 |
Inspect, test, remove, and replace water pump. |
P-1 |
| I.D.9 |
Remove and replace radiator. |
P-2 |
| I.D.10 |
Inspect, and test fans (electrical or mechanical),
fan clutch, fan shroud, and air dams. |
P-2 |
| I.D.11 |
Inspect auxiliary oil coolers; determine necessary
action. |
P-3 |
| I.D.12 |
Inspect, test, and replace oil temperature and
pressure switches and sensors. |
P-2 |
| I.D.13 |
Perform oil and filter change. |
P-2 |
