R 2500 P/U 2WD V8-350 5.7L (1987)
Intake Manifold: All Technical Service Bulletins
Engine - Blue/White Smoke On Startup
GMC NUMBER:
88-T-195
GROUP:
6A - Engine Mechanical
DATE:
February, 1989
CORPORATE
NUMBER:
836546R
SUBJECT:
BLUE/WHITE SMOKE ON STARTUP
MODELS:
1987-88 C/K/R/V/G AND P TRUCKS W/5.0L AND 5.7L (VIN CODE H AND K) ENGINES
Some vehicles may exhibit a puff of blue/white smoke on startup which is difficult to diagnose. Some hints on diagnosis and recommended corrective
action are listed below:
Throttle Body Injection (TBI) Trucks If the smoke is white or bluish white, occurs only at startup, and no unusual oil consumption is noted, then the joint
between the intake manifold and the cylinder head may be suspect. The intake manifold bolt torques should be checked. The intake manifold bolts
(particularly the two bolts nearest each corner) should be removed and the inside of the bolt holes in the manifold should be inspected for signs of
threading (grooves cut in the manifold by the bolts). If several of the intake manifold bolts have very low torque (10 ft.lbs., or less) and/or the manifold
bolt holes show signs of threading, the intake manifold should be replaced with the appropriate service manifold from the table below:
Engine
Intake Manifold P/N
All (5.0L and 5.7L) TBI
14102183
Parts are currently available from GMSPO. If no evidence of manifold threading is found, and the smoke on startup is definitely of a bluish nature or if
there is also a comment of oil consumption, the exhaust valve guide clearance should be checked for excessive clearance using the procedure outlined in
Section 6A of the appropriate Service Manual.
Use the following labor operations and times:
J0200 Replace Intake Manifold
C/K
- 2.0 Hrs
R/V
- 2.2 Hrs
G/P
- 2.7 Hrs
Add for Air Conditioning
C/K/G/P
- .2 Hr
RV
- .1 Hr
Cruise Control
G/P
- .2 Hr
RV
- .1 Hr