C 20 3/4 Ton Pickup 2WD V8-379 6.2L DSL VIN J FI (1982)
density at high altitudes.
The injection pump cannot be modified on the vehicle. The following procedure should be used:
1.
Remove the injection pump per service manual procedures. Be sure to note the relationship of the timing marks on the pump and front
housing. The pump must be reinstalled to its exact previous position.
2.
Send the pump to an ADS (Association of Diesel Specialists) Service Center for the altitude performance adjustment. The ADS service
centers will be advised by Stanadyne Corporation Bulletin as to injection pump recalibration procedures.
3.
Reinstall the pump per service manual procedure. The pump must be installed to its original timing setting. If the original
timing relationship was not retained, refer to Bulletin number 82-T-79 detailing the timing procedure.
ALTITUDE ADJUSTMENT LABEL
When LOW ALTITUDE vehicles are adjusted for high altitude operation, a SUPPLEMENTAL emission control information label must be
placed next to the existing underhood emission control information label. Wash off the area with soap and water, dry thoroughly, and apply
the new label, P/N 14057201.
The label should be ordered as regular parts and accessories through the General Motors Warehousing and Distribution Division system.
When ordering these labels via rapid entry, use order type CSD. Orders also may be placed on a PC 66 and mailed directly to GMWDD,
6060 West Bristol Road, Flint, Michigan 48554, attention Ship Direct Department.
After performing these adjustments, dealers should advise customers that, IF THE VEHICLE IS RETURNED TO CONTINUOUS, LOW
ALTITUDE OPERATION, THE PUMP MAY BE RECALIBRATED TO LOW ALTITUDE SPECIFICATION PER THE ABOVE
PROCEDURE AND THE SUPPLEMENTAL LABEL REMOVED.
Vehicles designed for principal use at high altitude (RPO NA6 - fuel injection pump, P/N 14050526, LH6 engine) perform satisfactorily at
low altitude without excessive smoke levels and need not be adjusted for extended operation at low altitude.
HEAVY DUTY DIESEL ENGINE (LL4)
No adjustments are applicable. Engine performs satisfactorily at low and high altitudes.
Technical Service Bulletin # 82C20
Date: 831101
Recall - Injection Pump Timing
Number:
82C20
Section:
6E November, 1983
Subject:
PRODUCT EMISSION CAMPAIGN 82C20 INJECTION PUMP TIMING MAY BE INCORRECT 1982 C, K, P LIGHT DUTY
TRUCKS EQUIPPED WITH 6.2L DIESEL ENGINE
TO:
ALL INVOLVED CHEVROLET DEALERS
General Motors has determined that certain 1982 C, K and P20-30 Series Light Duty Trucks equipped with RPO LL4 (6.2L diesel engine), NB2
(California Emissions) and a GVW rating of 8,600 through 10,000 lbs. sold for use in the State of California may have incorrect injection pump timing.
This over advanced timing may result in failure to comply with the California heavy duty emission standards.
To bring these vehicles into compliance with applicable California emission requirements, Chevrolet Dealers will retime the injection pump in
accordance with the instructions outlined in this bulletin.
VEHICLES INVOLVED
Involved are certain 1982 C, K and P20-30 Series Light Duty Trucks equipped with RPO LL4 (6.2L diesel engine) and sold for use in the State of
California within the following vehicle breakpoints:
Plant
From
Through
Flint Line #1
CF308441
CF329474
Flint Line #2
CF113757
CF128093
St. Louis
CS114318
CS134335
Pontiac
CV101556
CV117444
Involved vehicles have been identified by Vehicle Identification Number Computer Listings. Computer listings contain the complete Vehicle
