20585825 Volvo.Penta Flange

Models - Models AC5, 11AC, 15ACR, 17ACR, 18ACR, 23ACR, A115/45, A133/55, LR135-111, LR135-113, LR135-114 and LR150-160.
General
These are driven by the engine in the same manner as a D.C. Generator, namely, belt driven from the crankshaft pulley, but the advantage lies in their ability to provide higher maximum output at lower speeds, to cope with increased electrical load demanded by modern equipment and decreased road speeds owing to increased density of traffic, especially in built up areas. They are also much lighter in weight, output for output.As opposed to the DC Generator in which the armature windings rotate inside a stationary field system, the alternator has a rotating field system inside a stationary generating winding. When the rotor rotates inside the stator, the output produced is alternating current (AC). This is unsuitable for charging the battery which requires direct current (DC), so it is rectified by means of diodes which convert it to uni-directional flow to the battery.The alternator voltage output is maintained within close limits by means of a control box which is fully transistorised and functions as a fast switch.Precautions
As previously described the diodes in the alternator function as one-way valves and the transistors in the regulator/control box operate as fast switches. Both are accurate and sensitive.They do not wear out and cannot be adjusted, but because they are sensitive to voltage changes and high temperature, the precautions are vital to prevent them from being destroyed.a) DO NOT disconnect the battery whilst the engine is running. This will cause a voltage surge in the alternator charging system that will immediately ruin the diodes or transistors.b) DO NOT disconnect a lead without first stopping the engine and turning all electrical switches to the off position.c) DO NOT cause a short circuit by connecting leads to incorrect terminals. Always identify a lead to its correct terminal. A short circuit or wrong connection giving reverse polarity will immediately and permanently ruin transistors or diodes.d) DO NOT connect a battery into the system without checking for correct polarity and voltage.e) DO NOT "flash" connections to check for current flow. No matter how brief the contact the transistors may be ruined.Maintenance
The alternator charging system will normally require very little attention, but it should be kept free from build-up of dirt, and a check made if it fails to keep the battery charged.a) Regularly inspect the driving belts for wear and correct tension. It is important to ensure that all belts on a multiple belt drive have equal tension and are each carrying their share of the load. Slack belts will wear rapidly and cause slip which will not drive the alternator at the required speed. Drive belts which are too tight impose severe side thrust on the alternator bearings and shorten their life. Periodically ensure that the alternator is correctly aligned to the drive.b) Do not replace faulty belts individually in a multibelt system. A complete matched set of drive belts must always be used.c) Keep the alternator clean with a cloth moistened in kerosene or cleaning fluids. Ensure that ventilation slots and air spaces are clear and unobstructed.d) Remove any dirt accumulated on the regulator/control box housing, and ensure that cooling air can pass freely over the casing.Fault Finding on AC5
The AC 5 alternator is so designed that a flow of current indicated either by the extinguishing of the warning light, or as shown on the ammeter, is sufficient evidence that the system is in proper working order. Therefore, no open circuit, voltage or current output checks should be performed on the installation UNLESS:-a) The warning light fails to illuminate when the generator is stationary, and the switch is closed OR fails to become extinguished when the alternator is running.b) No charging current is shown on ammeter.c) The battery is flat.d) The battery is "boiling", indicating loss of voltage control.If any of the above symptoms occur, the procedure indicated below should be followed.a) Connect a good quality moving coil voltmeter 0-50 volts range across the battery or regulator negative terminal, and one of the three positive terminals marked LO, MED, HI. Disconnect alternator output terminal. Fit a good quality moving coil 0 - 100 amp ammeter in series with the alternator terminal and output lead. The battery should be in a charged condition.b) Close the warning light switch (master electric switch on dashboard) when the warning lamp should light up.c) Switch on a 10-15 amperes load such as lights, fans, etc., for fifteen minutes.d) Start engine