Mariner Mercury 105/140 JET, Service Manual

Page: 184 / 797

3B-24 - FUEL SYSTEMS 90-824052R3 JUNE 2002
Possible Cause Corrective Action
Low fuel pump pressure. Refer to Section 3A.
An anti-siphon valve.
Refer to Section 3A.
A needle and seat (in carburetor) that is either stuck
open or closed. (A needle and seat, that is stuck
open, will cause a flooding condition. A needle and
seat, that is stuck closed, will prevent fuel from en-
tering carburetor. Refer to ‘‘Carburetor Adjustments” in this section.
Improper carburetor jets, restricted jet or idle mixture
screw out of adjustment. Refer to ‘‘Carburetor Adjustments” in this section.
Improper carburetor float level. Refer to ‘‘Carburetor Adjustments” in this section.
Carburetor loose on reed block housing. Tighten carburetor nuts securely.
Reed block housing loose, or gaskets are defective. Using a pressure oil can, spray 2-cycle oil around
reed block housing/crankcase housing matching
surfaces and carburetor base. If engine RPM
changes, tighten or replace reed block housing gas-
kets or carburetor base gaskets, as needed.
Improperly routed or restricted bleed hose(s). Refer to bleed line routing in Section 4.
Thermal relief valve not functioning.
Stuck Open: Poor cold start characteristics.
Stuck Closed: Over rich at idle. Replace if neces-
sary.