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Zigzags Technology

2024

Video: Zigzags Technology

Video: Zigzags Technology
Video: Akyurek Technology Zig Zag Air Separator Working on Thyme 2024, March
Zigzags Technology
Zigzags Technology
Anonim

Science and technology are developing rapidly - and now in Russia there are already "boring" foreign cars that do not allow the fantasies of a repairman to take off. Another thing is our cars.

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Here is just one example. Who did not see the curves, like drunk, pulleys drive a pump or generator? A stamped-welded construction can hardly justify hackwork. Of course, at the very least, such a drive works, but the belt loads the shaft of the pump or generator with a variable moment, preparing the bearings for the fast end. Try to buy a good pump after that!

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But no less dangerous is the defect that our client encountered. The owner of the new (with a mileage of about 6000 km) Niva heard an unusual noise under the hood. It turned out that his car was originally a “drunk” pulley, but the owner did not pay attention to it. By the time we opened the hood, the pulley reached the condition shown in photo 1: two bolts of fastening turned out and flew away, and the part somehow rested on the rest. It remains only to congratulate the owner, because the situation was quite dangerous - near a radiator, injection system components, etc. If this "shell" fell off (most likely, at high speeds), who would predict the trajectory of its flight?

Well, why did the pulley fall apart? This is the result of his strong vibrations paired with a belt and variable stresses near the bolts. Steel, even if ductile, can break even from non-hazardous, at first glance, alternating stresses, if they act for a long time. At high voltages, the part naturally breaks faster. By the way, how to choose a pulley when buying? The main thing is not to rush, to inspect the part carefully, to press it with a plane with holes to the flat surface of the counter, measuring the height of the brook around the entire circumference. After installing the part on the car, also do not rush to put on the belt - first turn the shaft by hand: so evaluate both the pulley runout and the condition of the pump bearings.

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Continuing the theme of “quality”, take a look at photos 2 and 3. The exhaust valve of the VAZ 2103 engine served only about 3, 000 km - and burned out. Meanwhile, we already repaired the motor six months ago - then we installed new valves, wiped them well, replaced the caps, carefully adjusted the gaps. And then the client again appeared with a complaint. Like, the first cylinder does not idle, the engine “troits”, and in motion the cylinder seems to be connected, but only at revolutions above 2500 rpm. We immediately measured the compression: 3.5 kgf / cm2 with and without oil. Clear: a hole in the valve (with common problems with rings and piston, oil injection increases compression). Having removed the head of the block, we immediately saw a small fistula (photo 2). In the combustion chamber and on the bottom of the piston of the accumulation of greasy deposits - after all, the compression did not fall immediately - it decreased gradually, and at high revs the cylinder was connected from time to time, so that the piston and the chamber were somehow heated, but not enough for self-cleaning.

Who is guilty? The valve was not clamped - I guarantee it. We carefully studied the back of the cam. No sign of valve contact with the rocker. The width of the contact facet of the valve with the seat - about 1.9 mm - is strictly according to science. The saddle is excellent, the hub too. What to sin, except for heat-resistant surfacing on the edge of the valve? The chamfer burned (see photo 3) is rather strange - as if peeling off. Alas, I do not know how to check the heat resistance of valves when buying in a store. They put a new valve on the client (we rubbed it in, adjusted the gap), but the sediment remained on my soul: will something happen to the next?

Here is another miracle. Once a client rolled on a brand new injection Samara, the engine of which (VAZ 2111), with a mileage of only about 1000 km, began to twitch. The owner said that he did not believe the “guarantees” of the plant, therefore he turned to us immediately.

They started traditionally - backwaters, they say! Yes, the engine, one might say, “troil” - the contribution of the first cylinder to the total power was, it seems, negative. His candle was black, oiled - a clear sign of insufficient heat. The rest is fine. The ignition module, therefore, had nothing to do with it … Replacing the spark plug did not help - the engine still twitched. Compression? All cylinders are flat, about 13 bar. There is not the slightest hint of the situation described in the previous plot.

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In the end, they suggested the unlikely: is there any kind of camshaft gear? They removed the valve cover - and found the culprit of adventure! Here it is - in photo 4. The inlet valve cam disappeared - almost worn out under the root. The rest of the cams are great. Most likely, the factory managed to temper seven out of eight. We don’t know the details of the technology, and it’s hardly interesting to readers - let the local experts understand it. Well, the valve, naturally, as the cam weakened, opened less and less, and the first cylinder bothered the owner more and more.

The defect, as they say, is purely factory - even the most impenetrable guaranteemen would hardly be able to discern the fault of the owner. Maybe he still hurried to refuse the guarantee?

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