Help channel Promsvyazbank: 2200 0305 3314 4870 Ruslan Olegovich V. YUMoney: 4100 1178 3349 6761 Donate: https://www.donationalerts.com/r/varuol Guaranteed answer to the question here (indicate the email in the question): https://www.donationalerts.com/r/varuol WebMoney: Z350729664703 +79493142765 (MSK 8:00-17:00, day off Sat, Sun, WhatsApp, Telegram) Author of videos on the channel Ruslan Vasiliev We are on the Platform: https://plvideo.ru/channel/@gbcremont We are on Zen: https://zen.yandex.ru/profile/editor/... We are on RuTybe: https://rutube.ru/channel/24456048/ Playlist of repair technologies: • Repair technologies Playlist of valves: • Valves Playlist of valve seats: • Valve seats Playlist of bushings: • Guide bushings Correct welding, preparation of cylinder head, welding: • Cylinder head repair correct welding welding ... Correct welding, preparation of welding, welding: • Correct welding of cylinder head 2 preparation n... When and why is pressure testing needed: • Cylinder head repair Why is pressure testing needed and in... Gorlovka, Donetsk, Lugansk and the region. Our website: http://gbc2000.com/ We are on VK: https://vk.com/gbc_remont We are on YouTube: / @gbcremont Production of videos: [email protected] Hello everyone. Today I have a Chevrolet Orlando1.8 2012 cylinder head on my desk at work. The car was running on gas. Complaints: it eats a lot of oil, runs rough and, as it turned out, there is no compression. I didn't specify which cylinders, but we'll figure it out ourselves now, I hope. I take the feeler gauges and measure the existing gap. The first cylinder. The 10th on the exhaust does not fit on both valves. I take 5 hundredths. The second valve slips, but not on the first. That is, there is no gap at all on the first valve. I measure the next cylinder. The cams have turned up on the third, so we'll see here. The first in this cylinder or the fifth from the beginning of 5 hundredths also can't fit, it seems like the feeler gauge barely fits somewhere. It slips on the 6th valve. The tenth, of course, does not fit. On the remaining second and fourth cylinders, the 5 hundredths feeler gauge slips in all the gaps and even the tenth in some places. And so, let's remember. The 1st valve and the 5th valve have no gap at all. The situation is better at the intake. Feeler gauges of 1.5 to 2 tens fit there. I take apart the head. I remove the brackets. The sliding surfaces here are ideal. I remove the camshaft seals. They are in good condition. I also evaluate the degree of wear of the shaft journals and the cylinder head bearings. Everything is normal here. Yes, it is clear that all this worked, but the sliding areas are within tolerance and there is nothing critical. Let it go on these shafts and with this bed. I release the valve mechanism. I tap the valve plates with a magnetic, special valve spring compressor, loosen the crackers. Then I release the valves with a clamp valve spring compressor, removing the crackers. I extract the springs with the plates. The springs on the outlet are larger than the intake ones. More precisely, higher. I will need to unscrew the spark plugs as well. I mark the valves. And note that the first and fifth valves, which have no gap, are black and oily. I remove the valves. I roughly feel the gap in the bushings by tactile sensations. And here is the first valve. Here I discover that it has a burnout, which was not visually visible before. The seat has spread, but there is no burnout on the seat. I remove the rest, reach the 5th valve. I look at the chamfer and, apparently, there is a burnout there too. Without leaving the cash register, I grind the valve chamfer and see if this is true. As you can see, yes, there is a burnout there and quite a significant one. I remove the valves on the inlet side as well. At first glance, the gap in the bushings is normal everywhere. Well, we'll see later, when I wash the head in the sink from oil and other deposits in the bushings. I unscrew the spark plugs, I don't need them here at all. I pull out the valve seals. They are the most natural plastic and the hole is huge, i.e. this plastic did not compress the leg and did not perform the function of the seal. I will look at the seats. They are seriously spread out, but I will not change them. They can still be saved, there is still an opportunity to restore their chamfer. In the first place, where the valve burned out, there are dark places of fire breakthrough, I will clean it with a brush, I will see how critical these burnouts are. On the 5th seat there is also a dark seat without shine, a velvety coating. There was also a breakthrough. I will twist the valves for beating. All the others, except for the burnt valves, are normal both in terms of valve leg wear and curvature. I will need to buy two exhaust valves. After cleaning, I understand that the first seat needs to be replaced, the burnouts are deep. But on the fifth seat, it did not have time to burn out, although the valve itself burned out. The rest of the seats, due to the fact that they were pressed, but the gap was still there, they have only managed to creep apart at the moment. The intake is generally ideal against this background. We will narrow it a little and go ahead. Having agreed on the volume and cost of work, I proceed to the implementation of the repair. First of all, I clean mechanically, wash the cylinder head in a washing machine. After washing, I wash it with clean water and dry it with air. The head was washed perfectly.