Subject: Fuel Pump Diaphragm Leakage
Model and Year: 1958-61 V-8 High Capacity Fuel Pump (348 V-8 Type)
Source: Chevrolet Technical Service Bulletin
Bulletin Number: DR #474, Section VIm - (May 23, 1961)
TO: ALL CHEVROLET DEALERS
If fuel leakage occurs between the pulsator diaphragm and the fuel pump cover on the subject pump, Part #5624444 Fuel Pump Parts Package should be used for repairs.
This package includes a new oval shaped pulsator diaphragm, two new screws and lock washers. The new diaphragm shape prevents it from being pulled into the pulsator cavity by the pump vacuum. The pulsator cover screws with lock washers prevent loss of cover screw torque.
The new pulsator diaphragm, screws and lock washers were incorporated in Production and Service fuel pumps produced after December 19, 1960. These fuel pumps, listed below, can be identified by the pulsator diaphragm which extends approximately 1/4" beyond the pulsator cover.
PARTS DATA
| PART NO. | MODEL USAGE | DESCRIPTION |
|---|---|---|
| 5624444 | All Below | Fuel Pump Parts Package |
| 5621718 | 1959-61 Pass. 348 H.P. | Fuel Pump |
| * 5621665 | 1958-61 Pass. 348 1958-59 Pass. 283 w/F.I. 1959 Pass. 348 H.P. 1958-61 Corvette 1958-61 Truck V-8 |
Fuel Pump |
| 5621644 | 1958 Pass. 348 3 x 2 | Fuel Pump |
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.
© Copyright General Motors Corporation. All Rights Reserved
Article ID: 767
Created: August 3, 2014
Last Updated: August 3, 2014
Online URL: https://www.corvetteactioncenter.com/tech/knowledgebase/article/1958-1961-corvette-service-bulletin-fuel-pump-diaphragm-leakage-767.html