| 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 material of a head of cylinders). You make checks and control according to the following instructions. |
| Springs of valves |
| 2. For control of springs of valves control installation for check of springs has to be used. If it is absent 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 contract on the same value, it is a sign that they have approximately identical tension. But if the old spring contracts much stronger, than new, then it is a sign of fatigue, springs have to be replaced in a set. |
|
|
3. Spring length can be measured in a free state by a caliper, as shown in the drawing. Establish serially springs on a smooth surface (a glass plate) so that the closed round was from the lower party. Put a steel corner near a spring. 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. |
| Guides of valves |
| 4. Clear guides, dragging through directing the rag moistened in gasoline. It is better to clear cores of valves the rotating wire brush, having inserted it into a cartridge of the electric drill and holding near it a valve core. Insert serially valves into openings. For control of side plays of cores of valves in openings it is necessary to have the arrow indicator and a caliper. Check was already described for petrol engines, but on the diesel engine the internal diameter of the directing plugs has to 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 the internal diameter of the directing plugs. The result is a side play of cores of valves in openings which should not exceed 0,1 mm for inlet and 0,12 mm for final valves. |
| 6. Before replacing the 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 improved 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 has to be beaten out by a drift from the top party of a head of cylinders. Before beating of guides 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 a head of cylinders to 80–100 °C and beat out the old directing plug from the top party towards the combustion chamber. The drift has to have the selection suitable to internal diameter of the directing plug on the end. |
| 10. Measure by means of the arrow indicator the internal diameter of a reception opening in a head of cylinders. If the size is ranging from 13,0 mm and 13,027 mm, the directing plug with a nominal size of outer diameter can be installed. If diameter exceeds 13,027 mm, the directing plug with the increased size of outer diameter has to be installed. It means that reception openings under the directing plugs have to be chiseled in a workshop. |
| 11. Just do not try to hammer into plug openings with the increased size of outer diameter. If there is an experience with development, it is possible to develop openings to diameter of 13,050-13,077 mm for installation of the directing plugs of the increased size. |
| 12. If the directing plugs of valves are replaced, replaced also valves and it is necessary to grind in saddles of valves. |
| |
13. Clear internal surfaces of reception openings. Grease new guides and hammer them from the camshaft into the head of cylinders warmed to 90 °C so that the top end acted over the top surface of a head of cylinders on the size measured before removal of old guides. |
| 14. After a press fitting develop guides of valves development of 8,0 mm. Inlet valves have to have a side play of 0,02-0,055 mm; final valves have to have a side play of 0,035-0,070 mm. |
| 15. After replacement of the directing valves there have to be otfrezerovana of a saddle of valves. If saddles cannot be processed more, there is no sense to replace guides. |
| Saddles of valves |
| 16. Check saddles of valves (see rice. 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 have to be milled anew. The set corners are shown in the drawing rice. Saddles of valves. However it is necessary to provide the angle of correction 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 guides of the plug of valves are established. |
| 17. At first you frezernit a corner 45 °и then slightly process a mill 30 °и 60 ° or 75 °verkhny and bottom edge of a saddle to reduce width of a facet of a saddle and to reduce it in the middle. Width of a working facet of a saddle has to 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 have to get used. For this purpose apply grinding paste on a valve saddle surface and insert the valve into the corresponding saddle. Establish a sucker on the valve 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 facet of a saddle. |
| 19. The continuous opaque ring characterizes width of a facet of a saddle of the valve and it has to be visible on both details. Put with a pencil several hyphens on "ring" on a plate of the valve. Strokes have to be put around at distance of 1 mm. After that carefully lower the valve in the directing plug and a saddle and turn the valve on 90 °, with some pressure upon the valve (use at the same time a sucker). Again take out the valve and check whether pencil strokes from a facet were removed. If 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 has to make at inlet valves 0,9 mm, and at final valves of 1,0 mm. Otherwise it is necessary to install new valves. Measurement of valves is performed according to the 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 a measuring ruler on a head by means of a set of probes determine a gleam lengthways, across and by the diagonal of a surface of a head of cylinders. If it is possible to insert the probe the size more, than 0,20 mm, a head of cylinders are subject to replacement. The same control should be carried out also for the 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 compensation washer can be established. New saddles have to be hammered with the plastic hammer. At the same time a pin sideways saddles and a notch in a head of cylinders have to 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 install on well cleared head of cylinders the arrow indicator on the corresponding rack and deliver the measuring probe on a surface of a head of cylinders at the first subject to measurement of a saddle. Set an indicator scale to zero. Now move the measuring probe on edge of a saddle. The difference in indications has to make from –0,03 mm to +0,03 mm. If it not so, again remove a saddle and enclose under it a compensation washer. There is a number of washers from 0,05 to 0,10 mm thick, 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 have to be measured equally. |
| Camshafts |
| 24. Enclose camshafts pins of both trailer bearings in prisms or clamp the lathe between centers, and install the arrow indicator at one of average pins. Slowly turn the camshaft and read out indications of the indicator. If the deviation of an arrow makes more for one turn, than 0,06 mm, the camshaft are subject to replacement as it cannot be corrected. Further check necks of bearings and the surface of camshafts on lack of visible damages. If they still as it should be, it is necessary to measure height of cams and a side play of 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 of a side play of the bearing check lack of peeling 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. |
|
28. The side play of bearings 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 has to be turned forward and numbers of covers have to correspond. |
| 29. Line carefully covers with the hammer and insert bolts. Improve 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. Turn off covers of bearings again and at once check whether there was no Plastigase hair on a cover. Otherwise it sticks also to a bearing neck. |
|
31. By means of the template delivered together with Plastigase measure width of the compressed plastic hair in the widest place. It characterizes the minimum side play of the bearing. If the side play is more, than 0,10 mm, have to be replaced a head of cylinders and / or the camshaft to finish side plays in admission limits. |
| 32. For measurement of an axial side play of camshafts clear openings under bearings in a head of cylinders and covers of bearings and install the camshaft according to the above-stated description. Tighten bolts of covers of bearings for two or three passes. |
|
33. Install the arrow indicator, as shown in the figure 5.23, and a dviga to a yta the camshaft in both parties, taking of instrument reading. The received value is an axial side play of a shaft which should not exceed 0,25 mm. If the side play is more, it is necessary to replace the camshaft. Sometimes both details are exposed to wear. |
| Gear belt and gear wheels |
| 34. The belt with the broken teeths has to 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. Overwrite at turn of a roller demands replacement of the tension device of a belt. |
|
35. The returnable spring of the tension device has to have a certain length. At the same time length is measured between inside of hooks of a spring, as shown in the drawing. If the spring became shorter, than 51,93 mm, establish a new spring. |
| Pushers of valves |
|
36. Measure the internal diameter of openings under pushers in a head of cylinders and the outer diameter of pushers. For this purpose on hand there have to be internal and usual micrometers. The difference has to make no more than 0,10 mm. Otherwise pushers, and at worst a head of cylinders have to be replaced.
|
