What kind of key is needed for spark plugs

To tighten the spark plugs, special spark plug wrenches are used; they are measured by the diameter of the threads on them.

Spark plug sizes:

– 16 (mm) and 14 (mm): used for modern internal combustion engines; – 19 (mm): for motorcycle engines; – 20.8 (mm): old European standard; – 22 (mm): for old-style spark plugs for ZIL and ZIS cars; – 24 (mm): for M8 brand spark plugs.

21st key:

The 21st key is the standard 20.8 (mm) spark plug key, which is used on engines with two valves per cylinder. This key is considered the main one for almost all Soviet passenger cars.

All modern spark plugs, regardless of which company they are manufactured by or what features they have (for example, spark plugs with platinum elements), have a completely identical device.

They include components:

contact nut for high voltage wires;
insulator (heat-resistant ceramic);
a faceted metal insert on the insulator, used for unscrewing the spark plug with a key;
sealing ring;
lateral contact;
central contact.

There should always be a working gap between the last two elements (for injectors - about 1 mm) - in this gap a high-voltage spark will jump, igniting the working mixture in the cylinder (a separate spark plug is installed for each engine cylinder).

As for the period after which it is necessary to replace spark plugs on a VAZ 2114, it is: about 10 thousand km for simple budget-level spark plugs, about 15-25 thousand km for simple spark plugs from “branded” manufacturers, about 70- 100 thousand km for platinum/iridium spark plugs.

Signs that it's time to replace spark plugs

The above figures are approximate and should not be strictly adhered to. Sometimes even a simple candle can last longer than its allotted time, but a “branded” one may turn out to be of poor quality and quickly fail.

Incorrect “minor repairs” of flooded spark plugs by calcination or cleaning using coarse sandpaper also greatly reduce the service life.

Taking all this into account, replacing spark plugs with new ones should be done not according to some digital indicators, but guided by the following signs of their wear:

the color of the electrodes is different from brown and does not change after cleaning (white color indicates overheating, black/dark brown indicates problems with fuel combustion);
there is practically unremovable plaque/carbon deposits on the electrodes;

If at least one (and even more so several) of the above signs are found on the spark plug, then it should be replaced as quickly as possible. In order to do this, you will need a new spark plug and a VAZ 2114 spark plug key (we’ll tell you what kind of key this is below).

How to unscrew a broken spark plug?

The spark plug is a delicate element of a car's engine starting system. Careless movement or excessive physical force when unscrewing the spark plug can lead to its breakage. The lower threaded part will remain in the cylinder head and you will have to tinker a little to remove the broken part. In principle, there is nothing complicated and after spending a certain amount of time you can unscrew a broken spark plug.

Most often, breakdown of the spark element occurs when trying to replace it or clean it from soot and carbon deposits. Excessive force of the spark plug wrench or careless movement leads to damage to the integrity of the spark plug.

In order to unscrew a broken spark plug, proceed as follows:

Turn off the vehicle engine.

It is strictly forbidden to carry out work while the engine is running. There is a risk of electric shock or damage from rotating motor parts.

Wait for the engine to cool down.

The operation of a car engine causes an increase in the temperature of its main working elements. When performing steps to remove a broken candle, you can get a burn on your hand. There is one more rational grain in engine cooling. As you know, when heated, metal parts increase in size. Removing a broken spark plug on a hot engine in this state becomes simply unrealistic.

Disconnect the battery and contacts.

The terminals are removed from the battery and the contact from the broken spark plug is disconnected.

Clean the work area.

A special cleaning fluid can be used to clean the work area around the broken spark plug element. It perfectly dissolves carbon deposits and soot. Using an ordinary car compressor, it is recommended to blow out the spark plug well with compressed air.

To perform the following steps to remove a broken candle you will need:

-lubricating fluid WD-40 or Vedeshka . Its use will lubricate the threads of a broken spark plug and thereby facilitate the unscrewing process.

– extractor . A special wrench for unscrewing broken elements from hard-to-reach places. Despite the tricky name, it is a very convenient thing and is popular among car repair professionals.

– torque wrench . A special key that allows you to control the force aimed at unscrewing or tightening the element. Its use will make it possible to rationally use physical force and prevent the final failure of the thread of a broken element.

- unscrewing a broken spark plug

Vedeshka is used abundantly. The extractor is screwed into the broken spark plug. A torque wrench is used to control the force and prevent thread stripping. There is no need to rush and all actions should be as smooth and careful as possible.

After completely screwing in the extractor, you must begin to slowly unscrew the broken spark plug element. Movements are carried out counterclockwise. The torque wrench must be held level and straight. The appearance of a creaking sound and movement of a fragment of a candle indicate that “the ice has broken” and all actions are correct.

If you feel that the thread will break, you must stop active actions and add lubricant. There is no need to act through force, as you can break the thread and thereby “get money.” Drilling out a spark plug is a costly procedure and carries a risk of engine damage.

After removing the spark plug fragment, you need to carefully inspect the spark plug well for the presence of remnants of the broken element. You can use an ordinary carrying lamp or a flashlight. The thread should not have obvious damage, otherwise problems may arise with screwing in the new spark plug.

In principle, at this point the actions of unscrewing the broken spark plug can be considered successfully completed.

How to replace spark plugs?

Before considering the question of how to change the spark plugs of a VAZ 2114, you should first talk about how this can be done? The answer here will be very simple - a spark plug wrench.

They are available in a variety of shapes, lengths and sizes of the working part. The most important thing to consider when purchasing this tool is the size of the VAZ 2114 spark plug wrench. It should be exactly 21 mm, no more, no less. All other characteristics, for example length, are not so important.

We can only say that many experienced car enthusiasts and car service workers advise not to save money and to purchase a more expensive key with a universal joint and a handle. It is much more convenient to use than a regular tubular wrench with holes for a wrench or screwdriver.

Terrion › Blog › Spark plug wrench King Tony / Bahco / Jonnesway

The idea of having a convenient spark plug wrench came to me a long time ago, but out of habit I continued to use the domestic L-shaped wrench - simple (a hinged head and a metal handle) and at the same time terribly inconvenient. I had to experience particular difficulties with it when working with the spark plug of the cylinder outermost to the engine shield on Lex's inline six, where it was not possible to turn the key in a circle, which is why it constantly had to be rearranged.

Having acquired a set of Bahco tools, I was a little saddened by the fact that I got a large ratchet with an extension, but the 16 mm spark plug head I needed was not in the set. But this is precisely what made me go on a search and assemble myself a normal spark plug wrench.

I decided to start with the spark plug head. The choice fell on a Taiwanese instrument from Jonnesway that had the best price-quality ratio. A 16 mm spark plug head (S17H4116) cost only 100 rubles. and was immediately tested by me.

The metal part of the head did not cause any complaints, but the quality of the rubber from which the spark plug grip was made was thoroughly disappointing. Due to the fact that the hole in the rubber turned out to be too small, the candle simply did not fit there and, accordingly, was not fixed. I had to pull the rubber part out of the head and look at it up close. In the process of fairly careful removal, the rubber in the place where I grabbed it tore quite easily. In addition, when trying to pull the grip onto the spark plug manually, the rubber also cracked in the area of the hole.

Tips for replacing spark plugs

In addition to the above rules for replacing spark plugs, several more important recommendations should be mentioned. So, we have already told you what kind of spark plug wrench is needed for the VAZ 2114, but it’s worth adding that a torque wrench would still be ideal. It is worth tightening the spark plugs using it with a force of up to 20 N/m - this is the optimal force that securely holds the spark plugs in the socket and does not damage the threads.

The second tip is to check the spark plugs for manufacturing defects. So, if after installing a new kit the engine runs poorly and with extraneous noise, then one of the spark plugs is faulty. You can find out which one you have by disconnecting the armor wires one by one while the engine is running, and then connecting them back. During this procedure, the sound of the engine will change when the good spark plugs are disconnected, and will remain unchanged only when the wire from the defective spark plug is disconnected.

Tags: replacing spark plugs, fielder, spark plug won't come out

Comments 21

Under no circumstances should problem spark plugs (like this one) be unscrewed from hot aluminum heads. This happened in the old days on cast iron heads; you would either unscrew the aluminum together with the cut thread (the new spark plug won’t hold) or break off the threaded part of the spark plug (you’d have to remove the head). There is only one option - gradually soak. Buy a large bottle of VDeshka, and every time immediately after the trip, fill the well to the maximum. Don't try to twist it right away. Next trip - if the stop is for 2-3 hours, then fill it up again. After 4-5 times, try to move the candle from its place. If you go, don’t force it right away. Fill it in again and back and forth, gradually turning it out. Don’t be afraid that VDeshka will get into the cylinder and will burn out without problems the first time you start the engine.

thanks for the comprehensive information. What do you think about the mentioned tools for unscrewing broken spark plugs/bolts and nuts? forum.amadeus-project.com…sion/index.php/t4108.html

There are others of a different type and manufacturer. They are of little use. If the thread is not tightly clamped, then it will not come off the part, but if it is a serious case, like yours, they will not help, the extractor itself will simply break off. Tested many times on myself. They are sometimes needed in simpler cases...

Damn, something is not looking so rosy (((

the eyes are afraid, but the hands are doing...

WD rules! I think she was the one who helped me. I unscrewed it without any problems and without much effort after first filling it with Vedakh for 4 nights, and then driving as usual for a couple of weeks

This is interesting: Engine oil change intervals

I'm happy for you)))) good luck.

It’s better to really prepare yourself - buy a set of extractors, not this time, they’ll come in handy next time) Check out forum.amadeus-project.com...sion/index.php/t4108.html

Well, thank you! Very useful information. You need to take a closer look at this set))) But the author writes that it’s better not to turn it on when it’s hot, but everyone here advises trying. So again I don’t know what’s best to do

It’s better to really prepare yourself - buy a set of extractors, not this time, they’ll come in handy next time) Check out forum.amadeus-project.com...sion/index.php/t4108.html

I bought a set, but, thank God, I didn’t need it)))

I also had the same problem, it couldn’t be unscrewed... I made the lever bigger and as a result the thread from the spark plug remained in place and everything else broke off. I went to the specialists and they said either disassemble the engine or come up with a special tool and pick until you can unscrew it... so you don’t need any strength or intelligence for this at all situations

+1 You shouldn’t use strong force, pour in decarbonizer or kerosene, leave it for a day, then try to unscrew it...

Extractors are sold for such situations. Or the old fashioned way - you hammer in a triangular file and unscrew what is left of the thread.

there was the same situation

I also had stuck ones on my Mazda, and that’s all) And I also broke 2 spark plugs - the ones with a hinge. Then I took the head from the tool kit, then found a longer tube - it was used as a lever. I unscrewed it with a jerk. It’s only a pity that the iridium spark plugs I supplied for 590 rubles apiece lasted a little more than 20,000 km on our gasoline (

hmm...great. I'll try to unscrew the head with the pipe while it's hot

Hot and smoothly, without jerking! More leverage is better. I have heard more than once about broken candles. Okay, I’m stuck here, but some people very often in front of me start puffing and tightening these spark plugs, and I generally keep quiet about the wheel nuts - they can even start with their feet)…

why is all this necessary? Why tighten it so hard? After all, you’ll have to unscrew it yourself later. I'll try it hot

hmm...great. I'll try to unscrew the head with the pipe while it's hot

unscrew it together with the thread, good luck!

How could you break the key, or is it double-knocked? Take a key and a pipe, push a powerful thread into the hole, and push a pipe onto it to increase leverage, and twist it, whatever will do! And you have to change the candle!

yes, exactly, with a hinge and, apparently, Chinese. It broke under more effort. I tried to unscrew it with my dad’s pipe wrench - the handle that is inserted into the hole of this very pipe bends