Cruiselog Meter; Vacuum Gauge; Speedometer - Mercury MerCruiser MCM 454 Mag MPI Service Manual

Table of Contents

SERVICE MANUAL NUMBER 23

Cruiselog Meter

1. Connect jumper wire from positive (+) battery terminal to positive (+) gauge terminal.

2. Connect jumper wire from negative (–) battery terminal to negative (–) gauge terminal.

3. Observe gauge run indicator. If indicator is turning, gauge is operable; if not, replace

1. Disconnect vacuum hose from engine. Connect service vacuum gauge to engine and

IMPORTANT: Make sure that vacuum hose between gauge and engine is not leaking

and that all connections are tight.

2. If gauge readings are not within specifications, gauge is defective.

IMPORTANT: When testing speedometer gauge for accuracy, the air supply used for

the test must be regulated to the specified air pressure. Do not apply excessive air

pressure to speedometer gauge.

1. Apply air pressure directly to speedometer gauge (specified in chart) and note gauge

2. If gauge readings are not within specifications, gauge is defective.

90-861326--1 MARCH 1999

Downloaded from

https://needmanual.com/

record engine vacuum readings at idle, 1000, 2000 and 3000 rpm. Reconnect vacuum

hose and compare vacuum gauge readings (at specified rpm) with service gauge read-

ings. Readings should be within 3 inches of vacuum of each other.

reading. Light tapping of pressure gauge is required during accuracy check.

INSTRUMENTATION

Table of Contents