It is often enough to notice that exhaust pipe car has increased smoke. Sometimes situations reach the point that the car is literally shrouded in clouds of thick smoke. It is quite obvious that for every motorist the appearance of excessive smoke indicates the appearance of certain problems with.
We note right away that not always, but often increased smoke indicates serious. At the same time, it will not be difficult for experienced drivers to determine the cause by the color and composition of the exhaust. However, for beginners, it is not always easy to understand why the engine smokes, as well as to establish the cause and identify rings or caps. Let's figure it out.
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White or black smoke from the exhaust pipe
Let's start with the main types of smoke for a better understanding of the problem. So, White smoke from the exhaust pipe is quite normal for cold engine warm-up modes. Moreover, it is a mistake to believe that it is smoke. It's actually steam. Vaporized water is a natural product of the motor.
In unheated exhaust system this vapor partially condenses and becomes visible, and water usually appears at the end of the exhaust pipe. As the engine warms up, condensation decreases.
The colder the environment, the denser the steam. At temperatures below 10 ° C, steam is also formed on a well-heated engine, and in frost at minus 20 - 25 degrees it acquires a thick white color with a bluish tint. Humidity also affects the color and saturation of steam. The larger it is, the thicker the steam.
Note that if steam is visible in the warm season, it is quite possible that this is due to. Its shade depends on the composition of the coolant, weather, light, and also on the amount of coolant in the combustion chamber. Sometimes it can take on a bluish tint, resembling "oily" smoke. But, unlike oil smoke, which leaves a bluish haze in the air for a long time, the vapor quickly dissipates.
It is quite difficult for an inexperienced motorist to appearance determine what is the source of the smoke. In this case, you can use a proven verification method. To do this, on a well-heated engine, briefly close the cut of the exhaust pipe with a sheet of white paper, while the condensed vapor in the form of water droplets will gradually evaporate when it hits the paper and will not leave obvious greasy marks.
If this simple test confirmed that exhaust system it is steam that comes out, not oil smoke, it is necessary to take measures to eliminate the malfunction that contributes to the penetration of coolant into the cylinders.
Most often, liquid can enter the cylinders through insufficient traction (in winter, coolant leakage is often observed at the junction of the block and head), burnout, and less often as a result of formation. By opening the radiator cap or, it is easy to detect the smell of exhaust gases and an oil film on the surface of the coolant.
All problems associated with white smoke from the exhaust pipe require the elimination of not only direct causes, but also a mandatory check of systems that can affect their appearance: the switch on sensor, the clutch or the fan itself, the condition of the radiator, its plugs, hoses or connections. If white smoke and its accompanying defects are noticed, then the car cannot be operated, as the defects progress rapidly.
- We go further. Black smoke from the exhaust pipe indicates a re-enrichment of the fuel-air mixture or a deterioration in the combustion conditions of the fuel. Therefore, we are talking about malfunctions. Such smoke is usually clearly visible against a light background and represents soot particles - products of incomplete combustion of fuel.
Black smoke is accompanied by high fuel consumption, often poor starting, unstable engine operation, high exhaust toxicity, and often loss of power due to a suboptimal air-fuel mixture.
It is important to understand that monitoring the symptoms and quickly identifying the problem will further reduce the cost of repairs and avoid serious and rapidly progressing engine breakdowns.
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They are also called valve seals. Why do we need these very small parts? Their purpose is to prevent the flow of oil from the head of the block into the working cylinders through the valve stem. By design, the products are a steel sleeve, “wrapped” with rubber with a twisted spring. Today, acrylate rubber is used for the manufacture of valve seals - a durable and reliable artificial material.
Timely replacement valve stem seals prevents increased consumption oils and drop performance characteristics engine caused by agitation air-fuel mixture and lubricant composition.
Why are valve stem seals needed and how do they work?
The valve reciprocates due to direct contact with the timing camshaft. As it spins, an oil mist is created. In this case, the valve periodically enters the zone of the combustion chamber, where the presence of a lubricant is unacceptable. The valve stem seals just remove the oil from the valve stem, not letting it inside the cylinder block.
Over time, they age: rubber loses its elasticity, parts become stiff and lubricant begins to seep into the combustion chamber. In order to avoid excessive wear of the oil seals, they must be replaced in time.
Signs of worn valve seals
If it is possible to recognize the failure of these parts in time, then more serious engine breakdowns (parts of the cylinder-piston group) will be avoided. Main symptoms:
- Thick smoke with a white or bluish tint is visible from the muffler pipe: it appears for a short time when the engine is started.
- The concentration of smoke increases when you sharply press the accelerator pedal or change gears.
- Consumption lubricant increases markedly (more than 1 liter per 1000 km).
- Oiling is found on the spark plugs, they have black soot. This is due to the fact that when high pressure is created in the combustion chamber, oil particles are literally squeezed out through micro-gaps (enough 0.3 mm) in the candle thread and traces of lubricant consumables are visible even around the screwed candle.
Wear of valve stem seals cannot be avoided: these components of the gas distribution mechanism operate under increased load. In just one minute, the valve manages to make 150-1200 “walkers” (cycles). Plus, the products are affected by an aggressive environment: and exhaust gases.
The question arises, when to change the valve stem seals? If you bought a new car, then you need to do this after about 50-70 thousand kilometers (on imported cars mileage can be 180 or more thousand km).
If you ignore the above signs of oil seal wear, you should expect problems with the engine, namely:
- power reduction (the car will become worse “pull”) due to poor performance of oily candles;
- "swimming" revolutions on Idling;
- When the rpm drops, the engine may stall.
It is also worth paying attention to dynamic characteristics car - for example, acceleration, and fuel consumption. If these two parameters have not changed, then we can talk with a high degree of confidence about the wear of the valve seals. This is also indicated by the normal compression in the engine cylinders.
Replacement of valve stem seals
The duration and complexity of this process depends on the brand of car and the specific model. But the general principles of substitution can be stated. To successfully replace valve stem seals without removing the head, you must:
- Cool the engine completely and remove the valve cover.
- Match the marks on the pulley, distribution and crankshafts.
- Loosen the drive and remove the camshaft.
- "Dry out" the valve springs (it is better to use a puller).
- Using pliers or a special collet, remove the valve seals.
- Take new products, lubricate their inner surface engine oil. The same needs to be done with their seat.
- Slide the valve seals onto the stem and press them in with gentle blows with a rubber mallet.
- Put back the springs and dry them.
If there are suspicions that the valve stem seals have not been changed for a long time, you will have to remove the cylinder head and clean the elements of the cylinder-piston group from carbon deposits.
Replacing caps on VAZ 2121 (16 valves)
It is best to carry out this operation on the removed cylinder head. But if this cannot be done, do-it-yourself valve seal replacement can be done on the spot. You need to prepare in advance:
When everything is ready, you can go directly to the process. The algorithm of actions is as follows:
- Disconnect the positive terminal from battery, remove high voltage wires and remove the spark plugs.
- Set the top dead center, as you do when changing the timing belt (the marks on the camshaft, pulley, crankshaft must match).
- Take a 12mm socket wrench and remove the valve cover.
- Pull out the plugs connected to the sockets.
- Remove the ignition coil.
- Remove the throttle (if it is dirty, then take the opportunity to clean it).
- Dismantle the valve cover and unscrew the screws that secure the rocker arms (pull them out too).
- Take the squeezer and “dry out” the valves, after wrapping the device with a rag so that the valve retainers do not scatter in different directions. One part of this device is fixed, and the other presses on the valve disc, while compressing the spring and releasing the "crackers".
- If the valve, when exposed to a tool, goes into the combustion chamber, then you will have to insert into the candle hole wooden block, or similar device to stop the valve.
- Remove the worn valve stem seals from the bushings and press on new ones. Reassemble in reverse order.
It is worth taking seriously the choice of valve stem seals for the VAZ2112. Experts recommend the following kits:
- 2112-1007026: these are original products manufactured by AvtoVAZ and installed on the conveyor - ideal for a Russian car;
- setMaster-sport;
- Herzog;
- trialli;
- STD "Reserve";
- Goetze: this manufacturer is worth dwelling on. Most professionals prefer these products, despite the higher cost. The fact is that valve seals from this company are easier to install (the risks of damage are minimized) and they last longer than even “native” VAZ ones.
When buying oil seals for a foreign car, you need to consider the design of the caps. For example, on Japanese products, there is a protrusion on the inside that matches the corresponding groove on the sleeve.
It is clear that such valve seals cannot be installed on European, American or Russian cars. It is worth noting that removing and installing valve stem seals with your own hands will cost less, even taking into account the purchase of a “raskuharivatel”, than a trip to a car service. If there is no opportunity to immediately replace the valve stem seals, then you can try to delay the inevitable repair using special additives. They are able to seal the gaps between the valve and its stuffing box for some time. Autochemistry of this kind will cost less than replacing caps (even independently): it allows you to continue to operate the car for some time. The most commonly used additives include:
- Wagner (USA);
- Liqui Moly (Germany);
- Lavr (Russia).
Why You Shouldn't Drive With Worn Valve Seals
When lubricant enters the combustion chamber, fuel and lubricants are mixed, as a result of which the oil begins to turn into a combustion product and settle on the electrodes of the candles in the form of black soot. As a result, sparking becomes unstable, the motor is unstable and does not develop full power. Contamination of candles will sooner or later lead to the failure of one of the cylinders. Another threatening nuisance is the burnout of one or more valves. This is also fraught with cylinder failure and a sharp increase in oil consumption.
Insufficient closing of the valves leads to the appearance of varnish deposits in the cylinder head and on the piston group.
Criteria indicating wear of oil seals:
- regular appearance of soot on spark plugs;
- excessive consumption of engine oil;
- lack of stable idle speed;
- with a sharp increase in speed - copious emission of gray smoke.
Walkthrough Maintenance includes regular oil, air, oil and fuel filters. Valve seals are designed for vehicle operation up to 100,000 km. In fact, it is necessary to carry out the replacement earlier than the specified resource.
The device of valve stem seals (valve seals)
The oil seal has the shape of a cylinder with a truncated cone. For tight contact with the surface of the valve guide, a polymer ring with an expander spring is provided. A plastic (or rubber) ring removes excess oil when the valve stem moves, and the spring allows it to be tightly fixed on the stem.
For a long time, a rubber ring was used in the design of the stuffing box. Rubber and fluoroplastic options have appeared recently. This is due to the fact that rubber tans faster and loses its properties. Manufacture of the ring using modern polymers extends the life of the stuffing box.
Purpose of oil scraper caps
Long-term uninterrupted operation of the internal combustion engine is ensured by high-quality lubrication of rubbing parts. The oil distribution mechanism provides oil supply in a small volume. Camshafts in the cylinder head and piston group - need constant lubrication. The shaft rotates and a cloud of oil forms around it. The amount of lubrication is regulated by oil scraper caps.
Carbon deposits on the valve surface lead to incomplete closure and gap formation. Ignition occurs in the combustion chamber combustible mixture, and excess oil settles in the form of varnish deposits. When the valve is lowered down, the stem seal prevents excess oil from entering. Protects the piston group from plaque that occurs during the combustion of oil and fuel mixture. Oil seals are considered consumable items, as they need to be replaced periodically.
The location of the oil scraper caps in the engine
The head with camshafts and valves is mounted on the cylinder block. The valve stem moves through the guide bush. The thermal gap between the leg and the sleeve is closed with caps. The oil seal is positioned so that oil from the head does not enter the combustion chamber. The camshaft journals receive oil under pressure, and the rest of the nodes - due to splashing. Remove the engine head and camshafts, you can see the location of the glands in the valve seats.
Signs of worn valve stem seals
You can find out about the need for replacement without disassembling the engine. Valve stem seals have the following signs of wear:
- excessive oil consumption;
- bluish smoke;
- soot on spark plugs.
Worn seals increase oil consumption. This also happens when the piston group is "coked", but there is a visual difference. Visible oil streaks on the breather pipe. Blue-colored smoke exhaust is a sign that oil is entering the combustion chamber. "Tripling" of the engine and soot on the spark plugs are justified by the flow of oil through the stem seal. The car needs diagnostics and replacement of oil seals.
The service life of oil scrapers does not depend on the price and manufacturer. For budget and "premium" auto-resource is designed for mileage up to 100,000 km.
Oil seal replacement procedure
- Disconnecting the air filter, removing the cover and air ducts. Branch pipes and technical openings are closed with plugs. Remove spark plugs and cylinder head bolts.
- The piston in the first cylinder is set to top dead center. Removing the lock washer and star. The valve locknuts are released, and the adjusters are unscrewed to the stop.
- Crackers and springs are removed. The puller removes the seals. The bushings are lubricated with oil, put on the rod and installed with a hammer and a frame.
- Assemble components and parts in reverse order. After, the rest of the caps are changed in a similar algorithm in the order of cylinders 4 - 2 - 3.
Servicing each cylinder requires a 180 degree crankshaft rotation.
Self-replacement will require a special tool. The main specific device is the "raskuharivatel" of the valves. You will need it to replace the valve seal. Devices and materials:
- sets of socket and cap keys;
- head extension;
- rod and hammer;
- Collet clamp;
- pressing frame;
- tweezers;
- head gasket;
- set of new caps;
- sealant.
During the work, it is possible to replace the gaskets under the block and cylinder head. New oil seals are selected for a specific engine model.
Procedure for replacing valve stem seals
Consider how the valve stem seals are replaced by 8 valve engine without head removal
- Remove the fuel pump and air filter.
- We turn off the battery power and dismantle the ignition distributor.
- Unscrew top cover block, disconnect toothed pulley and mass.
- Evenly unscrew and remove the fastening nuts on the camshaft and bearings.
- We dismantle the shafts and seals.
- By turning the crankshaft, we raise the piston to TDC on the serviced cylinder.
- We insert a soft tin rod under the valve through the hole for the candle.
- Removing the springs special device and remove the plates. We replace the seals by pressing the old ones from the bushing and installing new ones.
- We assemble in the reverse order. We proceed to a consistent similar replacement on the remaining cylinders.
Before installation in the frame, the caps are lubricated with oil. They are pressed into the plate carefully, without sharp strong blows.
Gaskets and seals are installed under the bolt heads. Sort small items to avoid losing them.
After replacing all the valve seals, assemble the head by placing it on the sealant and a new gasket. Tighten the nuts with a certain torque, according to the instruction manual for this engine.
For various engines valve packing kits differ in design. Installation is carried out according to technical recommendations for a specific car model. When carrying out work yourself, adhere to the accuracy:
- coincidence of the diameters of the sleeve belt and the valve stem;
- the length of the seats of the guide sleeve and cap;
- installation on oil with reliable fixation (without the slightest backlash);
- selection of a set of caps for a specific engine model.
A high class of accuracy in the manufacture of parts allows you to increase the density of the connection and the complete coincidence of dimensions.
On sale there are additives for the restoration of oil seals. Their principle of operation is to soften the hardened rubber of the o-ring. Manufacturers differ in the quality of additives. There are different effects on rubber: no effect or excessive softening, which leads to excessive consumption of oil.
Good day to all
I have a 99 premaska. I got it in February - this is my first car :) So far I have invested a lot of money in it, starting from all consumables / seals and suspension parts, ending with soundproofing and replacing all the acoustics in a circle. Literally all this time, the machine was regularly in the services, because. did for himself and literally worked for her. At the very last moment, I left an oil change, because. the owner, who reported that the oil does not eat up, and the planned (every 10 tons) replacement will be in 3 thousand. Having left during this time (I didn’t travel much, occasionally on business) a little less than a thousand kilometers, I drove the gearshift knobs to adjust the loose backstage, and at the same time, earlier than indicated to me for replacement by 2 thousand. oil, because I was impatient to change it, I even bought 8 liters from a dealer so that there are no fakes, and rinse before, baying the second "set" next for the summer. Changed with a complete drain of the old at my request. Judging by the remainder in the canister, they filled in 3.5 with a filter replacement, which is the norm.
When I picked up the car, handing it back in the box, I noticed that I had smoked the entire repair box with white exhaust smoke. Standing nearby, went out to watch the exhaust. It smoked a little, then it seemed to disappear altogether. Calmed down, he took her to the painter for minor finishing touches (scratches, Kotska).
I was only able to pick it up after 3 days. Driving back from the stand, I noticed the smoke, again this smoke! Starting to finally understand that something is wrong here, I again observe the exhaust. It's warm outside, about +20 in the sun, noticeably warmer than on the day I picked it up from the service. The smoke, meanwhile, began to subside again as the engine warmed up. I ran my finger - there is condensate on the end of the pipe. Everything seems to be in order. The smoke is barely visible.
I decided to drive home around the city, bypass. During the route, periodically turned off the music, listened to the movement. Turnovers - as usual. The liquid temperature is in the middle of the scale. The oil pressure indicator and other things related to the engine on the tidy do not light up. Sounds are all right. Everything seems to be ok.
came and installed. Today I began to google, ask questions to motorists with experience. There were suggestions about the breakdown of the cylinder head gasket, etching of the coolant into the cylinder. The serviceman from whom I service the car (at the time of picking up the car, he was absent from the box), suggested by phone that these could be stubborn valve seals. The only question is that this smoke did not exist before.
And finally, almost the denouement - in the evening, having accumulated the theoretical course of a young fighter, I come to my Masa, check the coolant level, which is 2 centimeters in the tank, and under the radiator cap - under the neck, which seems to be excellent, I make sure that there are no whitish streaks on the oil filler cap neck of the engine and camshafts, I start the heart of the masyanya. Factory in a fraction of a second, then seven seconds of quiet, flawless work that seemed like an eternity. And suddenly! - as if fresh grass was thrown into the fire - thick white smoke begins to pour and slowly rise into the air. Dense smoke, obviously not condensate, and what the hell is condensate when it’s already over 20 degrees outside and in such conditions the exhaust activity should already be indistinguishable. Half a minute passed (no less), the density of the smoke decreased several times, becoming an exhaust visible to the eye. The father, who volunteered to help, at my request, adds gas at idle, and the smoke screen spreads across the yard with renewed vigor, hiding everything from view. During gassing, I tried to see the bubbles in expansion tank, which would indicate exhaust etching into the cooling system. NOTHING! The liquid, perhaps not having time to warm up, for all 5 minutes of engine operation did not even move anywhere, no bubble, no twitching, no oil stains on the surface of the liquid. Nothing: (Turning off the engine and opening the radiator cap, I also didn’t see any oil there. Under the oil filler neck, everything is also in normal mode, there is no emulsion on the dipstick, the oil level is closer to the maximum. Only the yard of 100x50 meters is half hidden in smoke. And it has a little smell gives off gasoline, not very reminiscent of oil, and the color is not gray or black, but white.And I did not wait for traces on a white sheet of paper attached to the exhaust.
In general, I'm completely confused.And finally, introductory (sorry for the end of the topic):
dvig- fp-de 1.8 petrol injector, mileage 178t
oil before change 5w-40 castrol synthetic http://castrol.com.ru/castrol/magnatec_sae40c.php
oil after change 10w-40 liquid moly semi-synthetics http://catalogue.liquimoly.ru/index....talogue_id=424
(the seller claimed that he did not reel, he did not need it). By indirect signs, I believed him then, now I don’t know.
Antifreeze - blue. Just blue :) the only thing that did not have time to change.
I chose the oil by studying the forums, since the engine was already running, semi-synthetics should be shown to it for use. Passed despite the seller's statement that he does not eat oil. So calmer. The figure of low-temperature density - in connection with the upcoming summer in Krasnodar (temperatures from 30 to 43 in the shade), I think that's what we need. I took Liquimoli through a friend, from a supplier, so that there are no fakes.
I confess, I did not measure the coolant level after the purchase, how could I know. Maybe the antifreeze was leaving - but as I wrote above, I did not see this by indirect signs. Unscrew option drain plug crankcase and look for the presence of a heavy water fraction at the bottom of the oil? or again unscrew the recently replaced candles and try to find "cleaner" ones from them, which, in theory, could "eat up" the coolant. Would you have time? moreover, replacing the old candles, I noticed that almost everything is fine with them. "Almost" - because the end is slightly coked, but the terminals of the arresters are clean and reddish, I threaded the edges - well, the mixture was over-enriched, I changed it because of this fuel filters(both) in the tank, and the air filter. I wanted to clean the nozzles with ultrasound myself or in the service during the week. So all these metamorphoses with the engine began to occur after an oil change in the service. Did the cunning owner use an anti-smoke additive in the old oil? But damn it, the smoke is now pouring out such that it can only be appeased by a young tree if it is driven into the exhaust.
Help, good people. It’s a pity for the machine, it’s scary to say how much I invested in it: (Ask questions, maybe I didn’t take something into account in my story. I’ll try to answer. Maybe one of my friends came across. I really look forward to advice. Of course, I’ll describe myself if I can (and have enough money) to solve this problem.