CAMPAIGN:INCORRECT RADIATOR CAP
SUBJECT: INCORRECT RADIATOR OR SURGE TANK PRESSURE CAP ASSEMBLIES INSTALLED
MODELS: 1994 P6S, B7T, C6H AND C3500HD MODELS
General Motors has determined that certain 1994 P6 Chassis, B7 Schoolbus, C6, C7 TopKick/Kodiak medium duty models and GMC. Chevrolet 3500HD cab chassis models may have been built with incorrect radiator or surge tank pressure caps. Vehicles with gasoline engines use a radiator pressure cap. Vehicles with diesel engines use a surge tank pressure cap. Incorrect radiator or surge tank pressure caps on C3500HDs can cause damage to cooling system and engine components. Incorrect radiator or surge tank caps on P6 Chassis, B7 Schoolbus, and C6 C7 TopKick/Kodiak medium duty models can cause reduced durability of the radiator.
To correct this condition, General Motors will send the correct radiator or surge tank pressure cap to each owner of specific vehicles involved in this campaign. The owner may inspect the installed radiator or surge tank pressure cap and replace it if required according to the procedure included with the correct cap. Or the owner may want to have the dealer inspect the radiator or surge tank pressure cap and perform the installation. The dealers will inspect the installed radiator or surge tank cap and install the correct cap that was provided to the owner if necessary.
VEHICLES INVOLVED
Involved are certain 1994 P6 Chassis, B7 Schoolbus, C6, C7 TopKick/Kodiak medium duty trucks and GMC, Chevrolet C3500HD cab chassis built within the following VIN breakpoints:
YEAR MODEL FROM THROUGH ---- ----- ---- ------- 1994 Topkick C6, C7 RJ500975 RJ501844 1994 Kodiak C6, C7 RJ100238 RJ100757 1994 GMC 3500HD RJ500976 RJ501832 1994 CHEV. 3500HD RJ100239 RJ100497 1994 CHEV. P6 RJ100237 RJ100442 1994 CHEV. B7 RJ100427 RJ100720 1994 GMC B7 RJ501505 RJ501821
The specific vehicles involved in this campaign have been identified by Vehicle Identification Number Computer Listings. These listings are furnished to all involved dealers with the campaign bulletin. Dealers should confirm vehicle eligibility through VISS (Vehicle Information Service System) or SERVICENET prior to beginning campaign repairs.
DEALER CAMPAIGN RESPONSIBILITY
Since a new pressure cap can be easily installed, for the owners' convenience, a new radiator or surge tank pressure cap along with installation instructions will be sent directly to owners of record. The owner may install the radiator or surge tank pressure cap or they may ask a dealer to do the service.
Dealers are to service all vehicles subject to this campaign at no charge to owners, regardless of mileage, age of vehicle, or ownership, from this time forward, if the owner does not wish to perform the pressure cap installation. All unsold vehicles in dealers' possession and subject to this campaign MUST be held and repaired per the service procedure of this campaign bulletin BEFORE, owners take possession of these vehicles.
Whenever a vehicle subject to this campaign enters your vehicle inventory, or it is in your dealership for service in the future, please take the steps necessary to be sure the campaign correction has been made before selling or releasing the vehicle.
OWNER NOTIFICATION
Owners will be notified of this campaign on their vehicles by GMC Truck Division (see copy of owner letter included with this bulletin). A listing of owner names and addresses has been furnished to the involved dealers to enable dealers to follow up with owners involved in this campaign. This listing may contain owner names and addresses obtained from State Motor Vehicle Registration records. The use of such motor vehicle registration data for any other purpose is a violation of law in several states. Accordingly, you are urged to limit the use of this listing to this campaign.
SERVICE PROCEDURE - See Figures 1 and 2.
CAUTION
! ------- Steam and very hot liquids from a hot cooling system can escape quickly and burn you badly when removing a radiator or surge tank pressure cap. Cooling system is under pressure, and if you turn the radiator or surge tank pressure cap (even slightly) steam and very hot liquid can come out at high speed. Never turn the cap when the engine and cooling system are hot. Wait for the engine and cooling system to cool if you ever have to move or remove a radiator or surge tank pressure cap.
1. Check installed radiator or surge tank pressure cap for correct part number (Figure 1).
2. If radiator or surge tank pressure cap is not correct install correct pressure cap.
Use the following procedure:
A. Park vehicle on level surface.
B. Allow engine/cooling system to cool completely (cool to touch).
C. After engine and cooling system are cool, carefully remove surge tank pressure cap on vehicles with a diesel engine or radiator pressure cap on vehicles with a gasoline engine.
D. Slowly rotate radiator or surge tank pressure cap to the left (counter clockwise) until it first stops, about 1/4 turn.
E. Wait for any pressure (indicated by hissing sound) to be released.
F. After all hissing stops, and all pressure is relieved, remove pressure cap completely by pressing down and turning the pressure cap to the left (counter clockwise) until stops.
3. Install correct radiator or surge tank pressure cap turning it to the right (clockwise) until it stops.
A. Arrows on pressure caps RC32 (6410619), RC33 (6410665)and RC36 (6410785) must be lined up with drain hose (Figure 2).
B. On cap RC12 (850994) make sure cap is fully turned to the right (clockwise) hard against the safety stop (Figure 2).
PARTS INFORMATION
A new pressure cap and installation instructions will be mailed to owners of record by GMC Truck on a no charge basis. If additional parts are required, they should be obtained from General Motors Service Parts operation (GMSPO). To ensure parts are obtained as soon as possible, order them from GMSPO on a C.I.O. order with no special instruction code but order under an advise code (2).
Part Number Description Quantity ----------- ----------- -------- 6410785 Radiator Pressure Cap, 1 3500 HD, Gas Engine(RC36)
6410665 Radiator Pressure Cap, 1 3500HD, Diesel Engine(RC33)
6410619 Radiator Pressure Cap, P6, 1 B7. C6, C7, Gas Engine(RC32)
850994 Radiator Pressure Cap, P6, I B7. C6, C7, Diesel Engine (RC12)
WARRANTY INFORMATION
If the owner requests the dealer to install the radiator or surge tank pressure cap, dealers should submit a warranty claim on each vehicle completed under this campaign.
Labor Operation *Time Parts Trouble Number Description Allowance Allowance Code --------- ------------ --------- ---------- -------- Cap, Radiator filler- V 8520 replace .2 $2.28 96
* For dealer to receive Administrative Time Allowance associated with this campaign, add 0.1 hour to the Labor Operation Time Allowance.
** The amount identified in the "Parts Allowance" column above represents 40% of dealer net for parts that are furnished in this campaign. This amount is to be placed in the Net Item Amount column of the claim and Type Code "M."
CAMPAIGN IDENTIFICATION LABEL
No Campaign Identification Label is required for this campaign.
ADMINISTRATIVE PROCEDURE
Procedures covering this campaign are outlined in Section V of your dealership's "GMC Truck Warranty Claims Processing Manual" #P9119.
Dear GMC Truck Owner:
As a valued customer, your complete satisfaction with your GMC truck is our goal. In keeping with this goal, we want to let you know that we have discovered a problem that could affect your vehicle and we want to take care of it at no charge to you.
On a number of 1994 P6 Chassis, B7 Schoolbus, C6, C7 TopKick/Kodiak, medium duty models, and C3500 HD Cab Chassis, such as yours, may have been built with an incorrect radiator or surge tank pressure cap. This condition could result in reduced durability of the radiator on the medium duty models or potential damage to the cooling system and engine components on the C3500 HDs.
Because a new radiator or surge tank pressure cap can be easily installed, for your convenience we have included with this letter a new radiator or surge tank pressure cap and installation instructions. The instructions are on the reverse side of this letter. However, if you prefer, your GMC Truck dealer will install the radiator or surge tank pressure cap for you.
Instructions for performing this service have been sent to your GMC Truck dealer. If you do not wish to install the radiator or surge tank pressure cap sent to you, please provide it to your dealer. Please contact your GMC dealer to arrange a service date as soon as possible. This procedure will take about five (5) minutes to complete, but you should ask how much additional time your dealer will need to schedule and process your vehicle.
The enclosed postage paid owner reply card identifies your vehicle. Presentation of this card to your dealer will assist in making the necessary correction to your vehicle in the shortest possible time. If you have sold or traded your vehicle, please furnish us the complete name and address of the person you sold or traded your vehicle to and retum the card to us.
We are sorry to cause you this inconvenience; however. we have taken this action in the interest of your continued satisfaction with our product.
GMC TRUCK DIVISION GENERAL MOTORS CORPORATION
INSPECTION AND INSTALLATION INSTRUCTIONS FOR RADIATOR OR SURGE TANK PRESSURE CAP -----------------------------------------------------------------------------
SERVICE PROCEDURE - See Figures I and 2.
CAUTION
! ------- Steam and very hot liquids from a hot cooling system can escape quickly and burn you badly when removing a radiator or surge tank pressure cap. Cooling system is under pressure, and if you turn the radiator or surge tank pressure cap (even slightly) steam and very hot liquid can come out at high speed. Never turn the cap when the engine and cooling system are hot. Wait for the engine and cooling system to cool if you ever have to move or remove a radiator or surge tank pressure cap.
1. Check installed radiator or surge tank pressure cap for correct part number (Figure 1).
2. If radiator or surge tank pressure cap is not correct install correct pressure cap.
Use the following procedure:
A. Park vehicle on level surface.
B. Allow engine/cooling system to cool completely (cool to touch).
C. After engine and cooling system are cool, carefully remove surge tank pressure cap on vehicles with a diesel engine or radiator pressure cap on vehicles with a gasoline engine.
D. Slowly rotate radiator or surge tank pressure cap to the left (counter clockwise) until it first stops, about 1/4 tum.
E. Wait for any pressure (indicated by hissing sound) to be released.
F. After all hissing stops, and all pressure is relieved, remove pressure cap completely by pressing down and turning the pressure cap to the left (counter clockwise) until stops.
3. Install correct radiator or surge tank pressure cap turning it to the right (clockwise) until it stops.
A. Arrows on pressure caps RC32 (6410619), RC33 (6410665)and RC36 (6410785) must be lined up with drain hose (Figure 2).
B. On cap RC 12 (850994) make sure cap is fully turned to the right (clockwise) hard against the safety stop (Figure 2).
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.
