Owners of classic Soviet motorcycles sooner or later face the need for a deep diagnosis of the electrical part. Checking the generator IZH Planet 3 is a critically important stage, since it is the stability of spark formation and charging of the battery that depends on the serviceability of this unit. Power problems are often masquerading as battery or relay malfunctions, which baffles even experienced motorcyclists on initial inspection.
Generator installation on the model IW Planet 3 structurally is a stator with windings and a rotating rotor with permanent magnets. Unlike automotive systems, there are no brushes, which makes the design reliable, but requires accurate compliance with the gaps and parameters of the windings. Any deviation in operation can lead to the "run away" of the magneto or the complete absence of a spark on the candle, making it impossible to start the engine.
To perform a quality diagnosis, you will need a basic set of tools, including a multimeter, a set of probes and possibly an oscilloscope for detailed analysis of the signal shape. It is important to understand that visual inspection often does not give a complete picture, as the interturn circuit can be hidden inside the coil. Therefore multimeter It is the only reliable way to assess the state of the electrical part of the generator.
Design features of the generator IL
Motorcycle generator system IW Planet 3 It is based on the Magdino located under the right lid of the crankcase. The basis of the design is a stator fixed on the crankcase, and a rotor mounted on a crankshaft. The rotor magnets, when rotated, create an alternating magnetic field that guides the EMF in the stator windings. The key element Here is the correct orientation of the magnets and the integrity of the wire insulation.
On the stator there are two main windings: charging (lighting) and high-voltage (for the ignition system). The charging winding is designed to power electrical equipment and recharging batteries, while the high-voltage provides a spark on the candle. Disruption of any of them leads to specific symptoms that are easy to diagnose, knowing the device of the node.
Why do the windings burn?
The main reason for failure of the windings of the IZH generator is poor quality insulation of the wires in combination with overheating. Also a frequent factor is working without a battery or with a faulty relay regulator, when the voltage in the network exceeds the permissible 14-15 volts, breaking the varnish on the wires.
It is important to note that the gap between the rotor and the stator must be strictly defined. If the rotor magnets touch the stator, this will lead to mechanical damage to the windings and jamming of the engine. Adjustment of this gap is made by shifting the stator or replacing the crankshaft bearings, if there is a production.
- โก rotor A moving part with permanent magnets, creating a magnetic field.
- โก Stator. - a fixed part with coils of copper wound, where current is generated.
- โก magneto - the general name of the ignition system from a magnet, characteristic of IL.
Visual examination and preparation for diagnosis
Before you take on the multimeter, you need to conduct a thorough visual inspection of the generator assembly. Often generator failure visible to the naked eye: blackened varnish on the windings, melted insulation of wires or obvious traces of short circuit. Remove the right cover of the crankcase, draining the oil beforehand or turning the motorcycle over to avoid it leaking out.
โ ๏ธ Attention: Before starting work, be sure to turn off the mass of the battery. Rotation of the rotor at closed contacts of the interrupter can cause a powerful spark discharge, capable of damaging the capacitor or ignition coil.
Check the status of the contacts and wires coming from the stator. Oxidation at the joints, especially under the terminals, creates additional resistance, which can be mistaken for a problem with the generator itself. Clean the contacts with small sandpaper and degrease them before taking measurements.
Note the condition of the capacitor, which is often attached next to the interrupter. Bloating of the body or the presence of an oily plaque indicate its malfunction. Although the capacitor is not part of the generator, its breakdown directly affects the operation of the entire ignition system, creating a false impression of a stator failure.
โ๏ธ Primary visual examination
Testing of resistance of windings with multimeter
The most accurate method of assessing the state of the generator is the measurement of the active resistance of the windings. To do this, switch the multimeter to the resistance measurement mode (Ohms) with a limit of 200 Ohms. Normal readings. For a serviceable generator, Planet 3 must be within certain factory tolerances, deviation from which indicates a defect.
Measurement is carried out between the windings. For charging windings, the resistance is usually about 0.4-0.6 Ohms, however, due to the low accuracy of the instruments at small values, it is better to estimate the relative value and absence of a break. The high-voltage winding (between the mass and output to the coil or interrupter) should have a resistance within 4-6 k Ohms (depending on the year of release and modification of the coil inside the stator).
| Type of winding | Normal resistance | Sign of malfunction |
|---|---|---|
| Charging (lighting) | 0.3 - 0.6 Ohm | Break or KZ (0 ohms) |
| High-voltage (ignition) | 4.0 - 6.0 kฮฉ | Breaking the isolation |
| Mass insulation | Infinity (โ) | Any value (breakdown) |
If the multimeter shows infinity where there should be resistance, then in a chain wirebreak. If the instrument shows zero or a value close to zero on the high-voltage winding, a short circuit has occurred. In both cases, the stator must be rewinded or replaced.
Diagnosis of interturn closure
The most insidious fault is the interturn circuit, which a standard multimeter may not reveal. And yet, winding-back The change is small, but the generator ceases to provide the necessary power under load. To identify such a problem, the method of comparing readings with a knowingly serviceable node or checking current output is often used.
One of the popular methods is checking with heating. When the engine is working, a faulty winding with a short turn will be heated much more than the serviceable one. However, this method requires caution not to overheat the insulation completely. A more professional approach is to use an oscilloscope to analyze the shape of the signal, but in garage conditions this is rare.
โ ๏ธ Attention: Do not try to check the generator "on the spark" by closing the wires on each other when the engine is running. This is guaranteed to cause a breakdown of the capacitor and damage to the contacts of the interrupter.
It is also worth checking the insulation status of the wires leaving the crankcase. Cracks on the insulation of high-voltage wire can lead to a leakage of current to the mass, especially in wet weather. Visually, such defects can be seen when dimming, starting the engine in the dark - you will see "dancing lights" or sparkling.
Use a contact cleaner spray to treat the connectors before measuring. This will remove the oxides and fat film, providing more accurate multimeter readings.
Checking the performance under load
Static resistance testing does not always give the full picture. For the final verdict, it is necessary to check generator under load. Connect the voltmeter to the battery terminals (or to the lighting winding terminals if the battery is not available) and start the engine.
At idle speeds, the voltage in the network should be at least 6-7 Volts (for a 6-volt system) or 12-13 Volts (for a 12-volt system). With increasing engine speeds, the voltage should increase, but not exceed the limit values controlled by the relay regulator. If the voltage does not rise or falls when the headlight is turned on, the generator cannot cope with the load.
Pay special attention to the verification of spark formation. Unscrew the candle, press it with a thread to the mass of the engine and spin the starter (or start the engine). The spark should be greasy, blue and skip between electrodes with a characteristic crackle. A weak, reddish spark indicates problems in the generator's high-voltage winding or capacitor.
- ๐ Voltage XXX It must be stable and correspond to the nominal value of the system.
- ๐ Growth in turnover The tension should increase proportionally.
- ๐ The color of the spark Blue indicates a good charge, red indicates a weak charge.
Typical malfunctions and ways to eliminate them
Analyzing repair practices IW Planet 3There are a few typical problems that can be identified. Most often there is a break in the wire at the exit point of the coil or melting of the insulation due to overheating. Rotor demagnetization is also common, although this is less common and usually after prolonged downtime or heavy impacts.
If the diagnosis showed a malfunction of the stator, the owner has two ways: rewinding or installing a new node. Rewinding requires special knowledge, the use of wires of the PETV-2 brand of a certain diameter and compliance with the number of turns. Critically important observe the direction of winding and the correct laying of turns, otherwise the generator will not work.
When assembling the unit after repair, be sure to check the ease of rotation of the rotor. It should not touch the stator at any point. The gap should be uniform throughout the perimeter. If the rotor is terminating, it is necessary to adjust the position of the stator or replace the crankshaft bearings.
Replacing a stator with a new one often saves time and nerves compared to rewinding, especially if there is no experience and special tool for winding the coils.
Frequently Asked Questions (FAQ)
What resistance should be at the windings of the generator IZH Planet 3?
For high-voltage winding, the norm is the range from 4 to 6 kฮฉ. The resistance of the charging winding is very small and is a fraction of Ohm (0.3-0.6 Ohms), so the multimeter can show a scatter. The main thing is the absence of a cliff (infinity) and the absence of a short circuit for the mass.
Why is there no battery charge, but there is a spark?
This indicates a malfunction of the charging (lighting) winding of the stator, while the high-voltage winding for ignition is serviceable. The problem may also be in the relay controller or in the wiring going from the generator to the battery.
Can I drive a Planet 3 without a battery?
Technically, you can start the engine and go, since the spark is generated by magneto independently of the battery. However, driving without a battery is dangerous for electrical equipment: at high speeds, the voltage can jump to critical values and burn the light bulbs or ignition coil. In addition, the light of the headlight will be strongly pulsed.
How to check the capacitor of the generator IZH?
The capacitor is checked by a multimeter in diode vertebrae or capacity measurement mode. When connecting the probes, the arrow (or numbers) must twitch and return to the original position (infinity). If the device shows zero, the capacitor is broken, if immediately infinity without reaction is a cliff.