How to Remove & Install an Alternator on a 1984 - 1995 Honda Civic / CRX / Del Sol
The alternator converts the mechanical energy which is supplied by the drive belt into electrical energy by electromagnetic induction. When the ignition switch is turned ON , current flows from the battery, through the charging system light or ammeter, to the voltage regulator and finally to the alternator. When the engine is started, the drive belt turns the rotating field (rotor) in the stationary windings (stator), inducing alternating current. This alternating current is converted into usable direct current by the diode rectifier. Most of this current is used to charge the battery and power the electrical components of the vehicle. A small part is returned to the field windings of the alternator enabling it to increase its output. When the current in the field windings reaches a predetermined control voltage, the voltage regulator grounds the circuit, preventing any further increase. The cycle is continued so that the voltage remains constant.
The alternator is located near the No. 1 spark plug at the front of the engine compartment. On models equipped with air conditioning, the alternator is mounted on a special vibration absorbing bracket at the driver's side of the engine compartment.
Several precautions must be observed with alternator equipped vehicles to avoid damage to the unit.
- If the battery is removed for any reason, make sure it is reconnected with the correct polarity. Reversing the battery connections may result in damage to the one-way rectifiers.
- When utilizing a booster battery as a starting aid, always connect the positive to positive terminals and the negative terminal from the booster battery to a good engine ground on the vehicle being started.
- Never use a fast charger as a booster to start vehicles.
- Disconnect the battery cables when charging the battery with a fast charger.
- Never attempt to polarize the alternator.
- Do not use test lamps of more than 12 volts when checking diode continuity.
- Do not short across or ground any of the alternator terminals.
- The polarity of the battery, alternator and regulator must be matched and considered before making any electrical connections within the system.
- Never separate the alternator on an open circuit. Make sure all connections within the circuit are clean and tight.
- Disconnect the battery ground terminal when performing any service on electrical components.
- Disconnect the battery if arc welding is to be done on the vehicle.
BELT TENSION ADJUSTMENT
If the alternator belt is cracked or has any damage, replace it with a new one.
- Apply a force of 22 lbs. and measure the deflection of the alternator belt between the alternator and the crankshaft pulley.
- On a belt in service (not new), the deflection should be for 1984-87 models: 0.28-0.39 in. (7-10mm); for 1988-91 models: 0.35-0.43 in. (9-11mm); for 1992-95 models: 0.28-0.41 in. (7-10.5mm).
A "new" belt has less than five minutes use, and therefore has not fully stretched. A slight amount of stretch is normal and accounted for when adjusting belts already in service. With these, a greater amount of measured deflection (slack) is permitted.
- If a new belt is installed, the deflection should be 0.25-0.35 in. (7-9mm).
- If the belt deflection is not as specified, loosen the alternator pivot bolt. On Civic and CRX, loosen the alternator adjusting bolt and move the alternator using a suitable prybar positioned against the front of the alternator housing. Tighten the adjusting bolt for 1984-91 models to: 17 ft. lbs. (24 Nm) when the proper tension is obtained. Recheck the belt deflection. Tighten the pivot bolt to 33 ft. lbs. (45 Nm).
REMOVAL & INSTALLATION
- Disconnect the negative battery cable.
- Remove the air cleaner assembly if necessary.
- Disconnect the electrical connectors from the alternator.
- Loosen the alternator adjusting bolt or nut and through-bolt and remove the alternator belt.
- Remove the alternator adjusting bolt or nut and through-bolt and remove the alternator. If necessary, remove the mount bracket bolts and the upper and lower mount brackets.
- Installation is the reverse of the removal procedure: put the alternator in place and re-bolt mount bracket (if removed).
- Follow belt adjusting procedure in the previous procedure to adjust belt and tighten the alternator through-bolt or through-bolt nut to 33 ft. lbs. (45 Nm). Tighten the alternator adjusting bolt to 17 ft. lbs. (24 Nm).
- Engage the electrical connectors and install the air cleaner assembly (if removed).