Rebirth of the Auto Giant

Chapter 77 Looking for carbon brushes

The starting circuit components of a car generally include battery → ignition switch → fuse → neutral start switch → starter relay → starter.

Here's how it works.

The neutral start switch is to prevent accidents caused by the car not starting in neutral, and a neutral start switch is set between the ignition switch and the starter relay. The neutral switch only works when the car is in neutral.

When it is turned on, the coil leading to the starter relay is turned on, and the starter relay is turned on under the action of magnetism. The electricity from the positive terminal of the battery will turn on the magnetic switch coil on the upper part of the starter.

The magnetic force generated by the magnetic switch coil causes the iron core inside to move backward, and under the action of the lever, the starter driving pinion extends outward to engage with the flywheel.

The magnetic switch continues to move backward, connecting the battery and the starter rotor, causing the starter to rotate, the driving pinion drives the flywheel to rotate, and the engine starts.

Wang Shi first checked in the fuse box to see if the starter fuse was intact, and then measured the ignition switch and it was normal.

Checked the starter relay and it was normal.

Wang Shi used an electric meter to bypass the magnetic switch and short-circuited the battery port of the starter to the port of the starter rotor.

No action.

"Master Wang, can you fix it now?" the other party asked.

"I don't dare to give you a guarantee now. I have to dismantle it and take a look inside to see the situation. As you know, there are no spare parts for Mercedes-Benz right now. If the starter assembly breaks down, we won't be able to find spare parts for a while.

You." Wang Shi said.

"Master Wang, just ask how much you want. I'm pressed for time. I hope you can help." After the other party finished speaking, he took out a stack of Hong Kong dollars, RMB, and US dollars from his black leather bag.

What does this boss do? Why does he have three currencies?

"I'll try my best to help you fix it," Wang Shi said. As for how much it will cost, you have to take it apart to see what the problem is.

Wang Shi called Lin Zhengtang over and asked him to guide him under the ditch to remove the starter.

After the starter was removed, Wang Shi opened it and found that the carbon brush was broken, and the circular copper piece behind the iron core of the magnetic switch that connects the battery to the starter rotor was also slightly corroded.

Taking advantage of this opportunity, Wang Shi explained the working principle of the starter to Lin Zhengtang.

"Is this the cause?" the customer who had been standing aside asked when he saw Wang Shi taking the carbon brush.

"Well, I don't know if this is available outside. I'll go look outside for you and see if there's anything suitable. If it doesn't work, I'll find a way, but it's hard to find this thing." Wang Shi said with a sigh.

The boss also knew what Wang Shi meant. Now Wang Shi wanted to raise the price, but even though he knew this, he had no choice.

"Master Wang, please help me repair it today. Please tell me how much it will cost."

Wang Shi thought for a moment, then pretended to be embarrassed and said: "As you know, this thing is imported. Generally, it is difficult to find a matching product in our country. I want to ask some friends to help me take a look. I have a friend at the General Logistics Department.

, If I can't find it outside, there is really no other way. I will ask him to help me look for it. You also know that people can't do it in vain, right?" After saying so much foreshadowing, Wang Shi meant that this matter is too troublesome.

It's troublesome, think about it for yourself, the money is definitely not cheap.

"I understand, I understand. Everything needs money now. Master Wang, you'd better give me a price and help me get it done as soon as possible. I can't wait any longer."

"Let's do this. I won't blackmail you. Let's discuss it. I'll charge you three hundred dollars. How about that?"

"Okay, it's just three hundred dollars. By coincidence, I have it here too." What else can you do? You've already dismantled my car. How can I say no? Even if it doesn't work, you have to do it.

The other party clearly knew that Wang Shi's price was a bit high, but he had no choice but to admit it. Who said that there is only such an auto repair shop in Beijing now?

"It's not a coincidence, and I saw it just now." Wang Shi secretly laughed in his heart, took the three hundred dollars from the other party, took two carbon brushes and rode outside to look for them.

"Master, I'd better go. I know a friend from an electrical machine factory. Maybe they can help." Wang Shi walked out, and his apprentice Lin Zhengtang caught up and whispered to Wang Shi.

"really?"

"Yeah!" Lin Zhengtang nodded.

"Okay, ride the bike and come back quickly, let them find the same one." Wang Shi handed the removed old carbon brush to the other party.

Carbon brushes are mainly composed of graphite containing copper and silver, and are square in shape. The technical content is not high, and some motor manufacturers also have them, but I don’t know if they are of the right size.

"Then master, I'm going."

"Go, Wukong."

After hearing this, Lin Zhengtang felt a little embarrassed and rode away on his bicycle.

Wang Shi and his customers waited in the store for half an hour, and Lin Zhengtang finally came back.

"How's it going?" The customer was even more anxious than Wang Shi. When he saw Lin Zhengtang coming back, he asked before stopping his bicycle and chasing him out the door.

"I found one." After Lin Zhengtang finished speaking, he came to Wang Shi and handed it to Wang Shi, "Master, can you take a look?"

Wang Shi took a look and found that the carbon head was a bit big and needed to be polished.

Use fine sandpaper to polish the carbon head to a suitable size, clean the copper contacts, and install the magnetic switch. Everything is ready.

Put the starter shell on the negative terminal of the battery, and then connect the positive terminal of the battery to the input port of the magnetic switch.

"Click, hiss!" First there was the sound of the magnetic switch, and then the driving pinion stretched out and rotated rapidly.

"This point is to connect the key switch in the car..." Wang Shi took this opportunity to teach Lin Zhengtang the starting circuit.

The other party listened very carefully.

After a brief talk, Wang Shi changed into old clothes and went downstairs to install the starter.

It can be dismantled by an apprentice, but there are still some details to install. Wang Shi has to do this himself. Besides, Wang Shi is too embarrassed to let his apprentice come for three hundred dollars, so he has to take care of it as a master.

After installation, let the customer try it out and troubleshoot.

"Oh, Master Wang's skills are indeed superb, and it has been solved. You don't know, I was always worried when driving, fearing that once the engine was turned off, it would never start again. Now it's finally solved."

“Celebrate the New Year with peace of mind!” Wang Shi said with a smile.

"Yes, yes, feel free to celebrate the New Year." The boss happily agreed after hearing Wang Shi's words.

After seeing off the client, Wang Shi took three hundred US dollars and took out five yuan from his pocket and handed it to Lin Zhengtang. He said to him: "Take this and give it to your friend, saying that I am thanking him for his help.

If necessary in the future, we may need to trouble him," Wang Shi said.

"Master, no need. He is my best buddy. His father is a master in an electric motor factory and specializes in this. This thing is also kept in their house." Lin Zhengtang said.

"Listen to me, we may have to trouble others in the future. We can't let others help in vain. A friend is a friend. Without his help, we wouldn't be able to earn three hundred dollars. This is an accessory channel. You have to treat it carefully and take it.

Then get on my bicycle and give this money to your friend." Wang Shi handed the other party five yuan.

Five yuan was a lot, but Wang Shi didn't feel sad at all.

If you have money, make money together. Of course, if you make the bulk of it yourself, why should someone else give you a red envelope if you help me?

Lin Zhengtang rode his master's bicycle to those friends' houses and handed each other five yuan.

"Zhengtang, tell your master no, it's just an ordinary thing in my house. It was all leftover when my father brought it back from the work to work overtime. I didn't expect to help you, how can I ask for your master's money? And this

Five yuan is too much."

"Yu Zhe, take it, otherwise I won't be able to go back and explain to my master. My master said that you deserve this, and I might bother you again in the future." Lin Zhengtang said.

When the other party hears this, what happens next? Okay.

Yu Zhe finally accepted the five yuan. His parents happened to be away, so the five yuan became his own.

Yu Zhe collected the money excitedly.

"Then I'm leaving. Come and sit in the store when you have time."

"OK, bye."