Volvo Penta 3.0 GS, Operator'S Manual

Page: 67 / 96

67
each plug until the interior of shell and entire insulator is cleaned. Avoid excessive blasting.
7. Examine interior of plug in good light. Remove any cleaning compound with compressed air. If traces of carbon or
oxide remain in plug, finish the cleaning with a light blasting operation. Clean firing surfaces of center and side
electrodes with several strokes of a fine cut file.
8. When spark plugs have been thoroughly cleaned, carefully inspect them for cracks or other defects that may not
have been visible before cleaning.
9. Use a round wire feeler gauge to check the gap between the spark plug electrodes. (Flat feeler gauges will not
give a correct measurement if the electrodes are worn.) Adjust gap by bending the side electrode only. Bending the
center electrode will crack the insulator. Setting the spark plug gap to any other specification in an attempt to
improve idle or affect engine performance is not recommended.
10. See the diagrams for correct installation of spark plugs and wires.
For proper engine performance it is very important that the correct spark plugs be used. When installing spark
plugs, make sure that the threads in the cylinder head and all surfaces on plugs and in cylinder heads are clean.
Tighten spark plugs the specified amount. All engines use tapered seat plugs without gaskets.
Do not operate engine if spark plug boots or high-tension leads are torn or cracked. This condition can allow
external sparks, which could ignite any fuel vapors in the engine compartment.
Spark plug wires must be arranged between the distributor cap and spark plugs in the order of firing sequence. If spark
plug wires are not correctly installed, misfiring or crossfiring will result.
Belt adjustments
To prevent possible injury caused by someone inadvertently starting the engine, remove the ignition keys
from each starting location (especially if the engine room/engine compartment cannot be seen from various
remote starting positions such as a flybridge or enclosed cabin).
(3.0 GS, 4.3 Gi, 5.0 Gi, 5.7 GSi, 7.4 Gi/GSi, 8.2 GSi)
These engine models use a serpentine belt, which is a continuous-loop belt threaded through the alternator pulley,
circulating pump pulley, idler pulley, and power steering pump pulley. This single belt replaces three separate belts
(alternator, circulation, and power steering). At least once per year, have your Volvo Penta dealer check the serpentine
belt for wear. An ideal time to have this check performed is when you have the gimbal bearings and universal joints
lubricated.
(4.3 GL, 5.0 GL, 5.7 GS)
The belts used for the alternator, water supply pump, and power steering
pump are heavy duty. Do not replace with automotive belts.
Belt tension
1. Belt tension is determined by belt deflection.
•
With the engine stopped, the belt should be tight enough so that it will
deflect ¼ inch (6 mm) when pressed with a finger, or 75
±
10 pounds (333.6
±
44.5 N) when using a belt tension gauge.
•
If the belt is too tight, excessive belt and bearing wear can occur.
•
If it is too loose, slippage can occur, resulting in belt wear, poor circulating
pump alternator, and power steering operation.
Circulating
pump
pulley
(Midpoint)
(Midpoint)
Alternator
pulley
Power steering
pump pulley
7797286 - Downloaded from www.volvopenta.com 19/05/2015 19:28:09