Fuel Delivery System - New Design
83saab01SUBJECT:
NEW FUEL DELIVERY SYSTEM
ISSUE: 06/83-635
FILE IN S.I. MANUAL:
VOLUME: I
SECTION: 2
PAGE: 153
A new fuel delivery system has been introduced from VIN Serial Nos. 01025853 and D2009881. This system was also batch tested in production on vehicles between VIN Serial Nos. D1014784 and D1018706. The new design places the fuel pump in a pressurized container which has a feed pump. This makes it unnecessary to pressurize the entire fuel tank, thereby eliminating the pressure valve which was formerly in the vapor line at the charcoal canister inlet.
Description, New Fuel Delivery System
The main fuel pump is unchanged from that used in the previous version but it has a new inlet strainer. It is located in the same part of the fuel tank suspended by a redesigned mounting collar. A container is joined to the main pump with an O-ring seal. The container has a safety valve in the top and a connection for the fuel return line at the side. A feed pump with "bow-tie" filter is fitted externally to the container. The electrical harness from the feed pump has a connection plug which is sealed with a grommet in the top of the tank behind the pump assembly mounting flange.
Function
The feed pump delivers fuel from the tank to the container surrounding the main pump. When the container is full, a pressure will be built up which prevents vapor bubbles in the fuel from entering the main pump. The safety valve opens at 0.1 bar (1.4 psi). The return line empties directly into the
container to ensure continuous fuel delivery when the fuel level in the tank is very low. Note, however, that if the car is run out of fuel, the engine may be hard to start without adding sufficient fuel. If two gallons of fuel or less is put into the tank the car must be level or the system will not reprime itself.
Service
^ REMOVING THE FUEL PUMP ASSEMBLY
Removal is carried out in the same manner as on the earlier version except that the connector to the feed pump and the hose clip for the return line must also be loosened.
^ REPLACING THE MAIN PUMP
1. Withdraw the pump from the container. Remove the rubber mounting collar.
2. Measure a distance of 46 +/- 2 mm (1-3/4 to 1-7/8 in.) from the top of the pump body and scribe a line at this distance.
3. Fit the mounting collar and press it down to the scribed line. Tighten the clamp.
4. Fit the pump into the container. Press the pump down far enough so that the distance between the edge of the rubber collar and the top of the container is 4 +/- 2 mm (1/8 to 1/4 in.)
^ INSTALLING THE PUMP ASSEMBLY
1. Connect the fuel return line.
2. Connect the feed pump harness.
3. Lower the assembly into the tank with the feed pump facing directly towards the rear.
4. Tighten the mounting collar clamp and connect the high pressure fuel line and harness to the main pump in the same way as the previous design.