| 1. Check wear of all details of a head of cylinders. Clear surfaces of a head of cylinders (for removal of the remains of old consolidation use a shaber, without scratching a material of a head of cylinders). Checks and control make according to the following instructions. |
| Springs of valves |
| 2. For control of springs of valves control installation for check of springs should be used. If it is not present on hand, the spring which was in the use can be compared to a new spring. For this purpose clamp both springs located one after another, together in a vice and slowly tighten a vice. If both springs are compressed on the same value, it is a sign of that they have approximately identical tension. But if the old spring is compressed much more strongly, than new, it is a sign of fatigue, springs should be replaced in a set. |
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3. The length of a spring can be measured in a free condition by a calliper, as is shown in drawing. Establish serially springs on a smooth surface (a glass plate) so that the closed round was from the bottom party. Put near a spring a steel corner. Measure a gap between springs and a corner in the top part. The admissible size depends on engine type. At an exit for the admission the spring is warped. |
| Directing valves |
| 4. Clear directing, dragging through directing a rag moistened in gasoline. Cores of valves are better for clearing a rotating wire brush, having inserted it into a cartridge of an electrodrill and holding near it a valve core. Insert serially valves into openings. For control люфтов cores of valves in openings it is necessary to have the strelochny indicator and a calliper. Check was already described for petrol engines, but on the diesel engine internal diameter of directing plugs should be between 8,01 and 8,03 mm. Diameter of a core of the valve makes 7,975–7,990 mm for inlet valves and 7,960–7,975 mm for final valves. |
| 5. Subtract diameter of cores of valves from internal diameter of directing plugs. The result is lyufty cores of valves in openings which should not exceed 0,1 mm for inlet and 0,12 mm for final valves. |
| 6. Before replacing directing plug, the general condition of a head of cylinders is checked. Heads of cylinders with small cracks between saddles of valves or between a saddle of the valve and the first round of a carving of an opening under a candle can repeatedly be established and be finished provided that cracks are not wider, than 0,5 mm. Check also a distortion of a surface of a head of cylinders that will be described below. |
| 7. For replacement of the directing plug the old plug should be beaten out by a drift from the top party of a head of cylinders. Before a vykolachivaniye directing follow the following instructions |
| 8. Measure by a depth gage or a measuring ruler, on how many the directing plug acts over the top surface of a head of cylinders. |
| 9. Warm up a head of cylinders to 80–100 ° With and beat out the old directing plug from the top party towards the combustion chamber. The drift should have the sample suitable to internal diameter of the directing plug on the end. |
| 10. Measure by means of the strelochny indicator internal diameter of a reception opening in a head of cylinders. If the size is in limits from 13,0 mm and 13,027 mm, the directing plug with the nominal size of external diameter can be established. If diameter exceeds 13,027 mm, the directing plug with the increased size of external diameter should be established. It means that reception openings under directing plugs should be chiseled in a workshop. |
| 11. Do not try to hammer simply into plug openings with the increased size of external diameter. If there is an experience with development, it is possible to develop openings till diameter of 13,050-13,077 mm for installation of directing plugs of the increased size. |
| 12. If directing plugs of valves are replaced, replaced also valves and it is necessary to grind in saddles of valves. |
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13. Clear internal surfaces of reception openings. Grease new directing and hammer them from a camshaft into the head of the cylinders which has been warmed up to 90 ° With so that the top end acted over the top surface of a head of cylinders for the size measured before removal of the old directing. |
| 14. After a press fitting develop directing valves development of 8,0 mm. Inlet valves should have люфт 0,02–0,055 mm; final valves should have люфт 0,035–0,070 mm. |
| 15. After replacement of directing valves should be отфрезерованы saddles of valves. If saddles cannot be processed more, there is no sense to replace the directing. |
| Saddles of valves |
| 16. Check saddles of valves (see fig. Saddles of valves) on lack of wear and sinks. Small signs of wear can be liquidated by a mill 45 °. However if the saddle was already strongly developed, saddles of valves should be milled anew. The set corners are shown in drawing fig. Saddles of valves. However it is necessary to provide a correction corner for correction of height of a facet of a saddle of the valve, that is it is necessary to use a mill 30 ° (inlet valves) or 60 ° (final valves). As it was already mentioned, saddles of valves can be milled absolutely if new directing plugs of valves are established. |
| 17. At first фрезерните a corner 45°и then slightly process a mill 30°и 60 ° or 75°верхний and bottom edge of a saddle to reduce width of a facet of a saddle and to reduce it in the middle. The width of a working facet of a saddle should make 1,2–1,6 mm for inlet and 1,6–2,0 for final valves. Finish milling works as soon as the facet of a saddle has width in the admission. |
| 18. Modifed saddles should get used. For this purpose put on a surface of a saddle of the valve grinding paste and insert into the corresponding saddle the valve. Establish on the valve a sucker and turn the valve in different directions. After grinding in carefully clear all details of paste and dirt and check a valve saddle at a plate of the valve and a saddle facet. |
| 19. The continuous opaque ring characterizes width of a facet of a saddle of the valve and it should be visible on both details. Put with a pencil some hyphens on "ring" on a plate of the valve. Strokes should be put around at distance of 1 mm. After that carefully lower the valve in directing plug and a saddle and turn the valve on 90 °, with some pressure upon the valve (use thus a sucker). Again take out the valve and check, whether pencil strokes from a facet were removed. If the width of facets of saddles of valves is in the set admissions, the head can repeatedly be established. Otherwise process saddles of valves or at worst replace a head. |
| Valves |
| 20. The description of valves of petrol engines belongs as well to valves of diesel engines. The size of edge of a plate of the valve should make at inlet valves of 0,9 mm, and at final valves of 1,0 mm. Otherwise it is necessary to establish new valves. Measurement of valves is made according to a size table and adjustments. |
| Head of cylinders |
| 21. Clear contact surfaces of a head of cylinders and the block of cylinders and check a distortion of a surface of a head of cylinders. For this purpose impose on a head a measuring ruler by means of a set щупов determine a gleam lengthways, across and by a diagonal of a surface of a head of cylinders. If it is possible to insert щуп in the size more, than 0,20 mm, a head of cylinders are subject to replacement. The same control should be carried out and for a surface interfaced to a collector. And here too we will allow a gleam of 0,20 mm. |
| Saddles of valves |
| 22. Saddles of valves in a head of cylinders can be replaced. Old saddles are beaten out from the top party of a head of cylinders in the combustion chamber. Under a saddle the compensatory washer can be established. New saddles should be hammered by a plastic hammer. Thus a pin sideways saddles and a notch in a head of cylinders should settle down on one line. |
| 23. After installation check, as far as saddles act over a contact surface of a head of cylinders. For this purpose establish on well cleared head of cylinders the strelochny indicator on the corresponding rack and deliver measuring щуп on a surface of a head of cylinders at the first subject to saddle measurement. Establish an indicator scale on zero. Now move measuring щуп on the saddle region. The difference in indications should make from–0,03 mm to +0,03 mm. If it not so, again remove a saddle and enclose under it a compensatory washer. There is a number of washers in thickness from 0,05 to 0,10 mm, that is it is easy to pick up the necessary washer for result of measurement. Hammer a saddle with the imposed washer and repeat measurement. All replaced saddles should be measured equally. |
| Camshafts |
| 24. Camshafts enclose pins of both trailer bearings in prisms or clamp between centers the lathe, and establish at one of average pins the strelochny indicator. Slowly turn a camshaft and read out indicator indications. If the deviation of an arrow makes for one turn more, than 0,06 mm, a camshaft are subject to replacement as it cannot be corrected. Further check necks of bearings and a surface of camshafts on absence of visible damages. If they still as it should be, it is necessary to measure height of cams and люфт bearings. |
| 25. For measurement of height of cams use a micrometer. Given sizes and limits of wear are given in size tables and adjustments. |
| 26. Before check люфта the bearing check lack of an otsloyeniye of metal of the bearing or formation of cracks. If covers are damaged, replace covers, camshafts and a head of cylinders. |
| 27. Clear covers of bearings and a neck of camshafts and spread out covers according to numbers of bearings. |
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28. Люфт bearings it is measured by means of a plastic hair of Plastigase (1). Impose a piece of this hair on all length of all pins and serially put on covers. The arrow on all covers should be turned forward and numbers of covers should correspond. |
| 29. Line carefully covers with a hammer and insert bolts. Tighten bolts in the direction from the middle outside the moment of an inhaling of 18 N of m. After that the camshaft cannot be turned. |
| 30. Unscrew again covers of bearings and at once check, whether there was on a cover Plastigase hair. Otherwise it sticks also to a bearing neck. |
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31. By means of a template delivered together with Plastigase measure width of the compressed plastic hair in the widest place. It characterizes minimum люфт the bearing. If люфт more than 0,10 mm, have to be replaced a head of cylinders and / or a camshaft to finish люфты in admission limits. |
| 32. For measurement axial люфта camshafts clear openings under bearings in a head of cylinders and covers of bearings and establish a camshaft according to the above-stated description. Bolts of covers of bearings tighten for two or three passes. |
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33. Establish the strelochny indicator, as is shown in drawing 5.23, and двига йте a camshaft in both parties, taking readings of the device. The received value is axial lyufty a shaft which should not exceed 0,25 mm. If люфт more, it is necessary to replace a camshaft. Sometimes both details are exposed to wear. |
| Gear belt and gear wheels |
| 34. The belt with the broken teeths should be replaced certainly. Other defects are cracks, attritions of lateral faces, or curves of some or all teeth. In this case it is necessary to check also teeths of cogwheels. Holding a natyazhitel of a belt with one hand, other hand turn a roller. Zatirany at turn of a roller is demanded by replacement of the tension device of a belt. |
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35. The returnable spring of the tension device should have a certain length. Thus the length is measured between inside of hooks of a spring, as is shown in drawing. If the spring became shorter, than 51,93 mm, establish a new spring. |
| Pushers of valves |
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36. Measure internal diameter of openings under pushers in a head of cylinders and external diameter of pushers. For this purpose on hand there should be internal and usual micrometers. The difference should make no more than 0,10 mm. Otherwise pushers, and at worst a head of cylinders should be replaced.
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