How to remove a generator from a scooter engine

The scooter generator is a very delicate part and sensitive to any load unusual for it.
Therefore, it should only be removed using special pullers. Any attempts to pull off the generator rotor using a pry bar or nail puller lead to the most dire consequences. For this work, you will need at least two pullers: one to fix the rotor, the other to pull the rotor off the crankshaft axle. You can make the pullers yourself - it’s not difficult, the design of the pullers is easy to understand from the photo. You can also buy pullers in a store. There can be no clear opinion about who likes what.

Remove the cooling casings and the cooling fan impeller. We insert the puller pins into the special holes on the generator rotor, secure it from turning, take a suitable socket wrench and unscrew the nut.

The design of the puller is easy to understand from the photo; you shouldn’t have any difficulties making it. There are also pullers of the same type, only factory-made.

We take the second puller, in our case it is homemade, using the standard bolts securing the engine cooling impeller - we screw it to the generator and tear the rotor off the axle.

The design of such a puller is easy to understand from the photo. An ordinary washer in which holes are drilled for different types of generators; a nut is welded into the middle of the washer into which a central bolt with a ball or cone at the end from another puller is screwed.

There is still a factory puller for this purpose, but it is designed for a specific scooter model, that is, to remove the generator from another scooter model you will have to buy a puller of a different size. A homemade puller is more versatile - drill new holes and voila! Well then, it’s up to you to decide.

To avoid accidentally damaging the generator windings, screw limiting nuts onto the bolts of the puller, which will prevent the bolts from coming out inside the generator.

Source

What is a voltage regulator used for?

The relay regulator stabilizes the voltage of the scooter generator at the required level, not allowing it to increase or decrease the value above or below the norm. This prevents on-board voltage surges from going beyond the established limits (depending on the boards this is 12-14 V) and ruining the work of consumers whose service life is designed to be no more than 13 V.

That is, this part takes on the impulses that arise during the operation of the scooter (turning on the headlights, the starter button) and transfers the resulting thermal shock to itself. In this case, all the heat that could settle on the contacts is generated in it and removed through the device.

In addition to stabilizing the voltage, the relay also converts alternating current into direct current, which is necessary for charging the battery.

Moped manufacturers install charging relays with different parameters on scooters and select them individually for each. Depending on the regulator circuit, the connectors also differ. Chinese models usually have 5 terminals (male), while Japanese models have 4.

How to remove a generator on a scooter - a detailed lesson with photos

The same alternator rotor puller does not fit all scooters, therefore, check the brand for the accessory of the puller. All this is indicated in online stores, so there should be no problems. At the moment there is an abundance of such pullers, and if you decide to get to the generator, do not try to do it without it. In any case, damage the winding and you will need to change the generator, which costs much more than the tool.

And here, in fact, he is. This puller is designed for Honda scooters and Chinese scooters with a 139qmb engine:

But you will need such a puller to remove the generator rotor on Chinese 150cc scooters:

There are also universal 2-in-1 models on the market, where the shaft can be rearranged and screwed on the opposite side. You can buy similar pullers in motorcycle parts stores or in online stores, for example, here: generator rotor puller. As you can see in the photo, here it is universal, double-sided.

On one side of the puller, an M24 thread is used with a pitch of 1 mm on the following scooters:

— Honda Tact; — Honda Dio; - Peugeot; - Kymco; — Chinese scooters with 139QMB engine; — Other models with a similar rotor. On the other hand, M27 threads are used with a pitch of 1 mm on Yamaha scooters, 4-stroke Chinese scooters with an engine capacity of 125-150 cc. and other models with a similar rotor.

Also, to fix the rotor, we need a special clamp, which can also be used to fix the clutch bell. This is what it looks like, I think we’ve already seen it:

Let's first decide whether it is necessary to remove the generator rotor on a scooter, what is there, and in what cases it needs to be removed.

1) Of course, if the generator breaks down or its windings are damaged.

2) Behind the rotor there is a hall sensor, which we will talk about below. This sensor is responsible for proper ignition.

3) Naturally, if the generator rotor itself is damaged and requires repair or replacement.

4) The crankshaft oil seal on the generator side is leaking and requires replacement.

5) Engine overhaul, in which you need to “halve” the engine, remove the crankshaft or, for example, the crankshaft bearings.

All these elements require removing the generator rotor on the scooter or the generator itself.

In today's lesson, we will use a Chinese four-stroke scooter as an example. Why Chinese? But because it is precisely these scooters that cause the most questions and problems. The principle of this action on a Japanese scooter is similar. The only difference is in removing the engine casing, but the principle is the same.

Procedure

To properly remove the generator from the scooter, use the instructions below:

Place your vehicle on the step and unscrew the side casing held on by 4-5 bolts;
After removing the casing, you will need to remove the impeller that allows you to cool the engine;
Then unscrew the nut on the shaft, which will become visible after unscrewing the impeller, using a wrench or a clamp;
Remove the hall sensor by first removing the plate on which it is attached.

It should be noted that the hall sensor and the generator itself are connected to each other by a single wiring harness coming out of the casing, which is why you will have to disconnect the wires to dismantle the generator. To do this, you will need to crawl under the plastic and carefully disconnect all the connectors.

After this, you will need to unscrew the two bolts that secure the generator and easily disconnect the last one.

During such work, you must carefully ensure that the bolts and nuts that secure the scooter parts are not lost, since you are unlikely to be able to find suitable components if they are lost.

When the generator is properly removed, you can proceed to repair it or install a new device. By acting carefully, you can not only preserve the generator, but also save on the services of specialists.

Homemade puller

Unfortunately, homemade, just like factory-made, is not without its drawbacks. It is moderately reliable, versatile, and cheap, but it is not so convenient to use, and if you do not know how to use it, you can easily break the threads under the bolts of the cooling impeller.

Which puller you will use is up to you to decide. I have described all the pros and cons of both options for you.

For myself, I chose the option with a homemade puller. And the price has nothing to do with it. It's all about experience. Over the years of work, I tried a lot of things and eventually came to the conclusion that there is nothing better than a homemade tool puller.

I screwed a bolt from a regular car puller into the nut, attached the washer to the cooling impeller, marked points with a pencil through the holes for the bolts, marked and drilled the holes.

If you don’t want to make a puller, buy a factory one at the store or ask your friends. Just before purchasing, just in case, remove the cooling impeller and look at the condition of the thread.

How to remove a generator on a scooter - a detailed lesson with photos

And here, in fact, he is. This puller is designed for Honda scooters and Chinese scooters with a 139qmb engine:

On one side of the puller, an M24 thread is used with a pitch of 1 mm on the following scooters:

Crankshaft restoration

Due to the fact that recently the vast majority of people have begun to look towards Chinese scooters, their number has increased. As you know, the quality is not at the highest level, but it is quite acceptable for trouble-free operation for 2-3 years or even more. I don’t want to write about factory scooters, because their quality is high (they keep the brand), but not all of them.

In general, this article is intended for all scooter riders without exception and does not have clear boundaries in the brand and year of manufacture of the scooter. We will consider the KShM - the crank mechanism of a 2-stroke engine.

Brief information: The crankshaft is designed to convert reciprocating energy into rotational energy. In other words, the crankshaft. This unit is not very complicated in design, but requires very precise weight distribution and proper installation. Also, certain conditions are required for normal operation.

similar for all scooters. I touched upon the Chinese because their raw material for the crankshaft does not meet any quality standards. Naturally, there are also normal ones, but, as a rule, they are installed on good Chinese scooters and fail very rarely. I had a case - they brought an AF34E engine removed from a scooter for repair. They said it is very difficult to start, pulls so-so, overheats and consumes fuel immeasurably. After a 1-2 minute diagnosis, it turned out that the radical dead were in the trash. He told me to come in 2-3 days. Imagine my surprise when I disassembled the engine... The indigenous people stood with Daelim (56-20-12), they were in a clear state. But the Chinese, self-installed knee

gave itself away immediately. The bearing seat on the crankshaft on the variator side was so broken that the crankshaft moved up and down by more than 1 mm. This is a very critical situation. The bearings had to be pressed out with a puller. And they put it on the knee so easily that no effort was needed at all. In general, the situation is bad, and I had to look for a replacement knee and resort to bearing seat analysis.

Factory puller

The rotor can be removed using either a factory puller or a homemade one. The option with a factory and homemade puller has its pros and cons. I'll start with the disadvantages of the factory puller.

The main disadvantage of a factory puller is its price. A factory puller is very, very expensive. About 500-600 rubles. But price is essentially not a very important criterion for me. Versatility, reliability, ease of use and durability are much more important to me. Unfortunately, the factory puller does not have all these advantages, except perhaps ease of use.

The versatility of the factory puller is zero and, unfortunately, it is only suitable for a certain series of engines. And if you need to repair a scooter that is not widely used in our country, then you will also have to buy a new puller for it. And this will be very, very difficult to do, since tools for rare models of scooters are as rare on sale as spare parts.

The reliability of the factory puller is extremely low. I won’t say that the problem is in the design itself, rather the opposite: the design is more than perfect. And it’s much more perfect. Nut + bolt - that’s all its design.

But the quality... There is something to discuss here. The quality of factory pullers leaves much to be desired. They are enough for literally several times, and I’m talking about expensive pullers for 500-600 rubles.

Cheap ones at 220-250 rubles in terms of quality are completely out of the question. Not only are they made of some kind of plasticine, but even this seems not enough for the manufacturer of this shit. He still manages to make them thinner or even thicker than necessary.

This is what the cheapest puller looks like, or rather, what’s left of it: a bolt from it is lost somewhere. It was used only once - the thread was immediately torn off, both on the puller itself and on the rotor, although before using this guan it was good there.

And even if you imagine the situation. that I will be able to buy a good branded puller, even if it costs 1,500 rubles, but it costs about that much. Where do I put the tusks (or rather, where do I get away from them?), who kill the threads under the puller and then, with an innocent look, roll their garbage dumps to me for repairs. There is no way to correct the thread on the rotor; it is not through.

This is what a high-quality factory puller looks like. Their prices are real - from 500 rubles and above.

Cons are minuses, but the factory puller also has its advantages. One of which is ease of use. And it is really convenient and easy to use. What's inconvenient about that? Screw it into the rotor, tighten the bolt and the rotor itself jumps into your hand.

Scheme and principle of operation

The operation of the stabilizer for all models is almost the same and consists in distributing the current supplied from the generator to stabilize it and further distribute it to consumers.

The operation of the stabilizer is almost the same for all models

The main peripheral consumers of the scooter include:

battery;
indicators;
light bulbs;
sensors;
enrichment agent;
other nodes;
starting enrichment.

How does the stabilizer work? The main principle of its operation is to act as a transformer, which lowers the voltage to an optimal level acceptable for the operation of electrical appliances, and also stabilizes the network and prevents unexpected power surges.

If the relay malfunctions, the scooter’s devices fail, quickly wear out or burn out.

To avoid these problems and their undesirable consequences, you should know the basics of the correct operation of the electrical circuit and voltage components of the scooter (Figure 1).

Voltage relay pinout diagram and wiring for main scooter models

How to unscrew the nut?

To fix the rotor, I sometimes use a homemade puller similar to the factory one. I made it from old unnecessary pieces of hardware, and it works no worse than the factory one.

If you don't mind the money, you can buy yourself a factory one. It is inexpensive and easier to operate than a steamed turnip: insert the pins into special holes in the rotor, rest the lever on something and calmly unscrew the nut. By the way, such clamps are sold not only in spare parts stores, but also in power tool stores.

In power tool stores, traders position this device as a universal wrench for loosening nuts on angle grinders (angle grinders). It’s called: “universal wrench for angle grinders.” It costs only 160 rubles, and the original, supposedly “correct” one costs 350 rubles.

If you buy the same one for yourself, immediately cut its pins, otherwise they are very long in stock and can damage the generator windings during operation.

Unscrew the bolts and remove the impeller from the rotor.

Let me digress a little: do not lose the bolts that secure the impeller to the rotor, but it is best to immediately remove them. I had the opportunity to repair a scooter, the owner of which lost the original bolt and tightened another one in its place, but it turned out to be a little longer and broke the windings when starting the engine.

The bolt was only a few millimeters longer than the original one.

We fix the rotor and unscrew the nut. As I already said: in my work I sometimes use homemade tools, in this case a puller.

We unscrew the nut and remove it together with the washer from the rotor. If the puck is not there, then someone has already managed to dig around there before you...

Crankshaft removal technology

Disassembling the engine to remove the crankshaft involves the following sequence of actions:

Wrap the engine connecting rod with a rag to protect the part from accidental damage.
Unscrew the screws securing the cover using a wrench of the appropriate size. In the case of a stud connection, instead of screws, you need to unscrew the nuts, but it is not necessary to unscrew the studs from the body.
Remove the engine housing cover. If the cover is difficult to remove, you need to use a puller. The puller is a strip with three holes. The crankshaft axle shaft is threaded into the central hole, and the other 2 have threads into which screws are screwed, which then enter the mounting holes on the engine housing.
Remove the bearings from the crankshaft using a special puller.

Before starting dismantling work, you need to drain the engine oil from the engine housing and wipe the contaminated parts with a rag. After removal, the dismantled crankshaft must be washed with kerosene, wiped thoroughly and dried.

Removing the rotor

Insert the bolts into the required holes. We take the bolts from the cooling impeller - they fit there perfectly. In order not to touch the windings, we screw restrictive nuts onto the bolts - they will not allow the bolts to go deep inside the generator.

We apply the puller to the rotor and screw the bolts into the holes. In order not to break the thread, slightly tighten the central bolt and see if all the bolts are tight. If any bolt is loose, tighten it.

This way we will evenly distribute the load between the bolts. If you neglect this moment, the entire load, unnoticed by you, can rest on only one bolt or two, and then they will break out of the rotor along with the thread. We don't need this, of course.

Now the main thing: what is there, you cannot tighten the central bolt by force. In this case, excessive force will not achieve anything. Everything must be done slowly and competently. Otherwise, you will tear the puller out of the rotor along with the roots, and then your budget will become completely financially insolvent.

You only need to remove the rotor this way: Lightly tighten the central bolt of the puller with a wrench, lightly hit the end of the central bolt with a small hammer - the rotor, usually, after the first blow, flies off the cone without talking, if it doesn’t fly off, pull the bolt again and hit again.

I learned this technique back in 1996, when I had the opportunity to remove the reel drive pulley of the Kolos combine harvester from the shaft. If it weren’t for one smart person who promptly told me how to work with a puller correctly, then I would have smashed both the pulley and the puller and the sledgehammer along with the combine...

The rotor sits on a key. If you do not plan to further disassemble the engine, leave it as is. And if you plan, you better get it, otherwise you’ll lose it.

A broken key can be easily removed with small pliers; if the key fits very tightly, leave it, it won’t get away from you.

So that you don’t have to guess later how your stator was positioned, we put marks with a core or take a photo, remember it, or do something else. This is necessary in order to protect yourself from problems with a lost outline.

It happens that when installing it back, the stator is installed in reverse, and then depending on your luck: everything may go without consequences, or the spark may disappear or interruptions may appear. To avoid this, any, not just CDI-type scooter generators must be installed exactly as they were originally installed. If you follow this golden rule, you will be happy.

We remove the stator. Installation of the generator is carried out in reverse order.

Photo report: How to remove a scooter generator?

The generator is not such a simple thing and you will have to work a little to remove it. Well, in addition to everything, if you don’t have at least the minimum material and technical base nearby, then buy pullers for one thing. Unfortunately, there is nowhere without them. Of course, you can do without pullers, and such precedents have already been encountered in my practice, but they are not what we will be talking about today.

On the one hand, people can understand: why buy an expensive tool for a one-time job. On the other hand, I don’t understand people: why buy and personally damage a scooter with a hammer, if you can give it to a mechanic for repairs? A dilemma, whatever one may say.

The generator consists of two main parts: the rotor and the stator. The stator is attached to the engine crankcase and can be removed very easily, literally “by hand”. But the situation with the rotor is different. The rotor is mounted on a cone and clamped with a nut, and it is clamped tightly, and in order to remove it from there, you must first secure it from turning, then unscrew the nut and only then use a puller to pull it off the cone.