GM Gasoline V6 90 Degree User Manual
Page 26
ENGINE APPLICATION MANUAL
GM Powertrain
Gasoline 4.3L V6 90 Degree
Revised: 08/15/2000
File: c:\data\manuales\v6-truck\am43v6#3.doc
Contact:Luis Nespolo - (248) 857-1558
Printed: 8/15/00
24
3.1.6.2 Back Pressure
Exhaust back pressure shall not exceed 8.5 inches of Hg at rated speed and load. Lower
exhaust back pressure is desired from a performance and fuel economy standpoint.
3.1.6.3 Packaging
The vehicle assembly plant attaches the exhaust pipe to the manifold with the proper
fasteners and a gasket or seal. Exhaust manifold takedowns will be 2 or 3 fastener designs.
Consult GM application engineer.
The current exhaust manifolds are made from Nodular Iron with incorporated and
detachable heat shields.
Fasteners at the manifold takedown must be capable of withstanding temperatures up to
800°C and will require stainless steel or sermagard coated steel. The gasket/seal must also
withstand these temperatures and will require stainless steel or stainless steel with mica or
grafoil.
The heat shield provided on the exhaust manifold will reduce radiant heat to nearby critical
components and reduce or minimize the number of separate shields required by the vehicle.
3.1.6.4 Exhaust Gas Recirculation (EGR)
EGR
P-Truck
C/K Truck
G-Van
M/L -Van
S/T Truck
( 6 L 3 )
EGR ASM Valve
17200268
17200268
17200268
17200268
17200268
3.1.6.5 Secondary Air
GMPT will indicate the needs for secondary air recirculation.
The following table shows the different Secondary Air and EGR Assemblies and
Components coupled to the L35 engine per GM platforms.
Engine Secondary Air
P-Truck
C/K Truck
G-Van
M/L -Van
S/T Truck
( 6T )
Pump Air Inj ASM
15059238
15053709
15056764
Hose ASM
15022544
N/A
15023825
Hose ASM By Pass
15022570
N/A
15760279
Stud
20513798
N/A
Washer
15953691
Strap
11509086
Bolt Screw
11508706
Pipe ASM
12561825
12562572
12561250/51
Check Valve (or Bypass)
12567731
12567745
15037955
Check Valve (or Bypass)
12567732
12567746
15056713
Bolt Screw
12558020
11515210
15695050
9440034
Gasket
12561871
12561871
12561871
Shield
15026631
Nut
11514596