Anyone who drives an old car understands that as soon as the starter goes wrong, the 4S shop opens its mouth and says “change the assembly”, less is a few hundred, more is thousands.

     But in fact, most of the time it's either the motor is broken, or the “motor teeth" (one-way clutch of the starter) are worn out-this thing can be done for tens to two hundred yuan, and it can be repaired in more than an hour by myself. Several bikers around me have tried it like this, and it is very reliable.Today, put the detailed steps together with the real case, and novices can follow suit

1.First figure out: what exactly is this “motor tooth”?

     The “motor gear” we are talking about, the scientific name is the one-way clutch of the starter, which is set on the shaft in the middle of the starter, and its function is very simple.：

When you twist the key, it will "pop out” and bite the flywheel ring gear of the engine, passing the energy of the starter to the flywheel to make the engine turn.；

     As soon as the engine catches fire, the speed is much faster than that of the engine, and it will “shrink back” to prevent the flywheel from dragging the starter in turn (otherwise the motor will burn).

Family cars are basically “roller-type“. The small rollers inside are clamped or loosened in the groove. After a long time, the rollers are ground and the oil dries out, and the problems of ”slippage“ and ”idling" will occur.

2.Don't dismantle it blindly!First judge if it's broken

     My neighbor's 06 corolla suffered from this disease last winter: it “hissed” during cold start, and the key had to be twisted 3 times to catch fire. The hot car was okay.At first, I thought it was a loss of power from the battery, but it was still like that when I changed the battery. Later, when I removed it, it was that there was sand and dust in the one-way clutch, and the roller couldn't get stuck.

Teach you 3 judgment methods, one test and one accurate：

Ignition idling: You can hear the starter “buzzing" when you turn the key, but the engine does not respond, like “light thunder does not rain”, this is because the teeth are not gritted.；

Multiple ignition: it can be fired occasionally, but it is getting more and more strenuous, from 2 times to 4 times, especially on cold days.；

Abnormal noise after starting: After the engine caught fire, there was a high-frequency sound of “whining”, indicating that the teeth did not shrink back in time and were ground by the flywheel.

     If the starter is completely silent after you twist the key, it is probably a problem with the battery or carbon brush, and it has nothing to do with this thing; if there is a sound of “metal hitting metal”, remember to take a look at the flywheel ring gear by the way (the case will be mentioned later).

3. Preparation work: You don't need many tools, just have these at home

When I repaired it for the first time, I used the tools I always had at home, and I didn't buy a new one.：

●Socket wrench (8-19mm, focus on 12mm, 14mm, for disassembling starter bolts)；

Slotted / phillips screwdriver (pry the buckle, remove the electromagnetic switch)；

●Needle-nose pliers (must be brought!Remove the circlip of the fixed teeth, otherwise it won't be able to be taken down)；

●Rubber hammer (gently knock on the stuck parts, don't use a steel hammer, it's easy to break the shell)；

●WD-40 (spray rusty bolts or stuck teeth, lubricate and remove rust)；

●Lithium-based grease (apply to the shaft when installing new teeth to reduce wear, don't use butter, it's easy to get gray)；

●The new one-way clutch (be sure to buy according to the model!Use the VIN code to check the original model. For example, the corolla corresponds to Denso 280-0101. Don't buy the “universal model”. My friend has suffered a loss and can't install it after spending money).

    In terms of safety, remember 3 points: first turn off the negative electrode of the bottle (red clamp positive electrode, black clamp negative electrode, remove the negative wire); pull the handbrake when the car is parked on the ground; wear gloves and goggles (the edge of the starter is pointed, don't scratch your hand).

4. Step-by-step repair: it takes more than 1 hour to get it done, and novices can also come

     Taking the Toyota Corolla I repaired as an example, it can be operated from the engine compartment without a lift. The steps are super simple.：

Step 1: Disassemble the starter-it is critical to find the right location

     The starter is generally on the side of the engine (near the flywheel), Corolla is on the left, and Lavida is on the right. It looks like “a cylindrical motor + a small cylinder (electromagnetic switch)”.

     Remove the wire first: there is a small plug on the electromagnetic switch, press and hold the buckle to unplug it; then use the 12mm sleeve to remove the nut on the positive electrode of the starter, don't lose the gasket；

Remove the fixing bolts again: the starter is usually fixed with 2 14mm bolts, and unscrew it with a sleeve (attention!The starter is a bit heavy, hold it by hand when the last bolt is about to be screwed, don't fall off and hit the water pipe)；

     Take it out: Slowly pull it out of the gap in the engine compartment and put a towel on the ground (don't get dirty, it's easy to go wrong when you put it back).

Step 2: Remove the electromagnetic switch-expose the "motor teeth”

     The electromagnetic switch is the “small cylinder” on the starter, which is responsible for pushing the "motor teeth” out.：

Unscrew the 2 small bolts of the electromagnetic switch (mostly cross or hexagon socket)；

There is a “push rod” at the bottom connected to the one-way clutch, and the electromagnetic switch can be taken off by gently pulling the buckle (put it away, don't lose the small parts).

Step 3: Remove the old one-way clutch-don't bounce the circlip

     The "motor teeth” are set on the “electric pivot” in the middle of the starter, and a small circlip is fixed to it.：

Clamp the circlip with pointed-nose pliers and gently pry it open (block it with your hands!The circlip spring has great elasticity and is easy to bounce and fly, so it's troublesome if you can't find it)；

     If the tooth is stuck, spray WD-40 in the gap between the shaft and the tooth, wait for 5 minutes, gently knock on the side of the tooth with a rubber hammer, turn while knocking, and slide down slowly (don't use brute force, the shaft will be useless if it bends)；

     Clean: Use sandpaper to gently rub off the rust on the armature, and then wipe it clean with a cloth (the new teeth have to slide in, they have to be clean).

Step 4: Install new teeth + reset-test one-way function

     Apply grease: Apply a thin layer of lithium-based grease to the armature (don't apply too much, it will grind quickly if it is stained with ash)；

Install new teeth: align the spline on the shaft and slide in gently (to be able to rotate freely, but not shake)；

Snap back the circlip: Use needle-nose pliers to snap the circlip back to the slot at the end of the shaft and confirm that it is clamped tightly (if it is not clamped tightly, the teeth will fall off when starting).

Step 5: Install the electromagnetic switch and starter back

     The push rod of the electromagnetic switch is aligned with the slot of the new tooth, and the fixing bolt is screwed back (don't tighten it too tightly, the plastic shell is easy to crack)；

     Test first: turn the new teeth by hand-it should “not turn clockwise, but can turn counterclockwise” (one-way locking function). If you turn it upside down, you will install it upside down.； 

     Install the starter back: align with the original position, first screw 1 bolt to fix it, then screw the rest, and tighten it diagonally (the force is uniform, don't be crooked)；

     Connect the wire: first connect the positive electrode cable, and then plug in the small plug of the electromagnetic switch (if you hear the ”click" sound, it's plugged in tightly)；

     Connect the negative electrode of the battery: finally install the negative electrode wire and tighten the nut.

Step 6: Try to start-once you get in the car, it will be successful

     Try twisting the key: there is no slippage, and it will catch fire once, indicating that it has been repaired; if there is any abnormal noise after the engine starts, it will be fine if there is no problem.After my Corolla was repaired, it was cold-started once, which was smoother than before.

5. Real car owner cases: You may have encountered these situations too

     Just saying that the steps are not enough, put a few real cases of bikers around you, and see how to deal with different situations, which is more reference.

Case 1: 06 corolla cold start slippage-caused by sand and dust

     Owner: My neighbor Lao Zhang, the car drove 160,000 kilometers and started to get sick last winter; symptoms: Cold start “hissing”, you have to twist the key 3 times, occasionally better after the hot car; diagnosis: Remove the starter and take a look, the one-way clutch is full of sand and dust, the lubricating oil is cured, and the roller can't get stuck; repair: Replaced with a Denso one-way clutch (about 17 US dollars), after cleaning the armature, it was coated with lithium-based grease, and a dust-proof cover was added (to prevent further ash); 

     cost: accessories + working hours total about 29 US dollars, which is more than The 4S store said that the “replacement assembly” (about US 887) saved nearly US 660; follow-up: It has been used for almost a year now, and there is no more problem.

Case 2: 16 Sylphy models start idling-the bearing is broken

     Owner: My colleague Xiao Li, the car has driven 190,000 kilometers; symptoms: The starter is “buzzing” when starting, the engine does not respond, and occasionally it can be hit; Diagnosis: Remove it and find that the bearing in the one-way clutch is broken, the rollers are all loose, and the gap between the electric pivots is also large (standard ≤0.1mm, measured 0.3mm); repair: replaced a sub-factory one-way clutch (about 11.6 US dollars), replaced the electric pivot with a new bearing (about8.7 US dollars), and also sharpened the commutator; cost: accessories + working hours total about For 29 U.S. dollars, the 4S store said it would change the assembly (about 116 U.S. dollars), saving nearly 90 U.S. dollars; reminder: If the gap between the shafts is large, don't just change the teeth, and check the bearings by the way, otherwise the new teeth will not be used soon.

Case 3: 12 Accord models start with abnormal noise-the flywheel ring gear is also worn

     Owner: My friend Lao Wang, the car has driven 220,000 kilometers; symptoms: There is a sound of “metal hitting metal” when starting, and occasionally it can't catch fire; diagnosis: The teeth of the one-way clutch have been dented, and the flywheel ring gear is missing a few teeth; repair: Replaced Hitachi's one-way clutch (about US 332) + new flywheel ring gear (about US 551), and adjusted the stroke of the electromagnetic switch (the previous teeth were not fully extended and powered on); cost: A total of about US 1105, although it is more expensive than the first two, but it is better than changing the starter assembly (about US约51). 217 U.S. dollars) is still half saved; lesson: You must look at the flywheel ring gear before installing the starter!If the ring gear grinds, the single-way clutch will still ring, and it will cost nothing.

6. Must-see for novices: don't step on these 3 pits

     The pit that my bikers and I have stepped on, don't do it again：

Don't buy “universal” teeth: the axle diameter and number of spline of each car are different. For example, Honda has 10 teeth and Toyota has 12 teeth. If you buy it wrong, you can't install it. My friend bought a universal model             before, but returned it and bought it again.；

Don't miss the disassembly and installation of the iron wire: some cars have a small black iron wire on the starter. When they are disassembled, they must be unloaded together. When they are installed, they forget to connect them, and the starter will not turn on when it is powered on (I forgot about it the first time I repaired it, and it took half an hour to find out)；

     Don't save grease: Be sure to apply lithium-based grease before installing new teeth, otherwise the shaft and teeth will dry out and it will not take long to break. Don't use butter, it will be easy to harden in winter.

7. Follow-up maintenance: let the "motor teeth" last longer

     It doesn't matter if you finish the repair, you usually pay more attention to these 3 points, which can prolong your life.：

Regular greasing: remove the electromagnetic switch every 30,000 kilometers and spray some grease into the groove of the one-way clutch；

     Don't start frequently and short: don't start for more than 5 seconds each time, and the interval between the two starts is more than 10 seconds, otherwise the teeth will easily overheat and wear out.；

     Don't wade too deep on rainy days: the one-way clutch will rust when the water enters. I had a biker who didn't care about it after wading in the water, and it slipped again in half a year.

8. 3 questions frequently asked by bikers

Q1: The novice has never repaired the car, can it be done?

     A friend of mine hadn't even used the sleeve much, so he followed the steps to dismantle it slowly, and it was done in 1 and a half hours.The key is not to panic. Remove the parts and put them in order (for example, put the bolts in a small box), and don't lose the circlip. If the case is really stuck, spray WD-40 and wait for a few minutes.

Q2: Can the old one-way clutch be repaired?

     Basically can't be repaired!Most of the rollers are worn out or the springs are broken, and the accessories are not easy to find. Even if they are barely repaired, it will not take long to break. It is better to replace them directly with a new one, which is a few tens of dollars. Worry-free.

Q3: After the repair, it still skids, what's the matter?

     The high probability is that the flywheel ring gear has been ground (like Lao Wang's case), or the new gear model is wrong.First look at the ring gear: you can see from the installation hole of the starter that if the tooth is missing or flattened, you have to change it; then check the model of the tooth, don't buy it wrong.

     In fact, the maintenance of old cars is really not that mysterious. For small problems like the one-way clutch of the starter, find the right time and do it yourself. Not only can you save a lot of money, but you can also figure out the“temper” of the car-next time there is a small problem, you don't have to be led away by the 4S shop.Many bikers around me said after the repair: "It turned out to be so simple, I knew I would have done it a long time ago!”