Skoda Fabia

Since 2000 of release

Repair and car operation

2.12.2. Дефектовка

THE GENERAL DATA

Details of a head of the block of cylinders of engines of 1,0 l, 37 kw and 1,4 l, 50 kw

1 – a valve cracker; 2 – a plate of a spring of the valve; 3 – a valve spring; 4 – маслосъемный a cap; 5 – a block head; 6 – the valve; 7 – заглушка

Valve saddle

a – diameter of a saddle; b – the maximum admissible size of processing; c – width of a working facet; z – the bottom plane of a head of the block

Measurement выступания the valve over a basic surface of a spring in a head of the block of the engine

And – the size from an end face of the valve to a basic surface of a spring of the valve on a block head

Distance measurement between an end face of the valve and the top plane of a head of the block of the diesel engine of 1,9 l, 74 kw

And – distance from an end face of the valve to the top plane of a head of the block

Backlash measurement between the valve and the directing plug


Measurement of an axial backlash of a camshaft


Check of planeness of a head of the block of cylinders

1 – a ruler; 2 – probe; 3 – a block head

Measurement of height of a head of the block of cylinders of the engine in volume of 1,4 l

And – height of a head of the block of cylinders

The sizes of the valve

And – diameter of a plate; b – diameter of a core; c – length of the valve

PERFORMANCE ORDER

1. After dismantling clear all details of a dirt, a deposit, oils and so forth 2. Check up planeness of a surface of a head of the block adjoining to the block of cylinders. For this purpose put a metal ruler an edge on a head surface at first in the middle along a head axis, and then on diagonals and measure probeом a backlash between a plane of a head and a ruler, as is shown in drawing (fig. Check of planeness of a head of the block of cylinders see). The Maximum permissible backlash for petrol engines makes 0,05 mm, for diesel – 0,1 mm. 3. If the measured backlash exceeds maximum permissible, it is necessary to replace a block head. At petrol engines of 1,4 l, 55 and 74 kw surface polishing, but thus height is supposed and the head should not be less than 108,25 mm (fig. Measurement of height of a head of the block of cylinders of the engine in volume 1,4 see). If as a result of polishing the head height appears less, it is necessary to replace it. The prevention After polishing of a head of the block it is necessary прошлифовать saddles of valves on the same size on what прошлифована a head that valves have sat down more deeply, otherwise they will hit about pistons. 4. At engines of 1,0 l, 37 kw and 1,4 l, 50 kw check up, whether strongly sits in place заглушка 7 (fig. of the Detail of a head of the block of cylinders of engines of 1,0 l, 37 kw and 1,4 l, 50 kw see) if is not present – replace it. For this purpose beat out old заглушку. Put hermetic Loctite 270 on perimetre new заглушки and запрессуйте it заподлицо in a block head. 5. Examine a head: if in combustion chambers there are cracks or traces прогара, it is necessary to replace a head. At diesel engines small cracks between saddles of valves if their width does not exceed 0,5 mm are supposed. Replace valves with deep risks and scratches on a working facet, with cracks, core deformation, короблением plates, traces прогара. Superficial risks and scratches on a working facet can be deduced grinding in of valves. 6. In specialised masterful working facets of valves with damages which cannot be deduced grinding in, it is possible прошлифовать on the special machine tool. At grinding it is necessary to sustain the sizes specified in tab. the Sizes of valves and resulted in drawing (fig. the Sizes of the valve see). 7. Check up a condition of springs of valves: bent, broken or with cracks replace. 8. Examine hydropushers of valves if on their working surfaces there are teases, сколы, deep scratches, traces of step or non-uniform deterioration, replace pushers. 9. Examine camshafts if on their necks and cams there are wear tracks, teases, сколы, etc., shaft it is necessary to replace deep risks. 10. Check up a condition of saddles of valves. On working facets of saddles there should not be wear tracks, bowls, corrosion and so forth Insignificant damages (etc.) can be deduced small risks, scratches grinding in of valves. 11. In specialised masterful working facets of saddles with damages which cannot be deduced grinding in of valves, it is possible прошлифовать or профрезеровать. The Saddle of the valve and in tab. the Sizes of saddles of valves are specified In fig. the sizes of saddles of engines of 1,0 l, 37 kw and 1,4 l, 50 kw which need to be sustained at processing. It is preliminary necessary to calculate as much as possible admissible size of processing of saddles. For the specified engines this size is defined as follows:       – Insert the valve into a head and press to a saddle. It is necessary to insert that valve which will establish in this saddle;       – Measure the size and (fig. Measurement выступания the valve over a basic surface of a spring in a head of the block of the engine see) from an end face of the valve to a basic surface of a spring of the valve on a block head;       – Calculate the maximum admissible size of processing of saddles under the formula: b = a max - a, Where b – the maximum permissible size of processing of saddles, mm; a max – maximum permissible выступание the valve (the tab. Maximum permissible выступание valves see) over a basic surface of a spring on a block head, mm; a – the measured size from an end face of the valve to a basic surface of a spring on a head, mm. For example, for the inlet valve of the engine in working volume of 1,0 l the measured distance and is equal 42,7 mm, then b = 43,1 - 42,7 = 0,4 mm, i.e. the maximum depth of processing of a saddle – 0,4 mm. 12. If as a result of calculation b it will be equal 0, it is necessary to repeat measurement with the new valve; if and in this case the zero turns out, it is necessary to replace a head. 13. At diesel engines of 1,4 l, 74 kw the distance and (fig. distance Measurement between an end face of the valve and the top plane of a head of the block of the diesel engine of 1,9 l, 74 kw see) from an end face of the valve to the top plane of a head of the block is defined as follows:       – Insert the valve into a head of the block and press to a saddle. It is necessary to insert that valve which will establish in this saddle;       – Measure the size and;       – Calculate the maximum size of processing of saddles under the formula: b = a - a min, Where b – the maximum size of processing of saddles, mm; a – the measured size, mm; a min – the maximum permissible size from an end face of the valve to the top plane of a head of the block. 14. The maximum permissible size is equal for the inlet valve of 43,4 mm, for final – 43,2 mm. 15. For example, for the inlet valve измереное the distance and is equal 44,1 mm then b = 44,1 - 43,4 = 0,7 mm, i.e. the maximum depth of processing of a saddle is equal 0,7 mm. 16. If as a result of calculation b it is equal to zero, repeat measurement with the new valve; if and in this case the zero turns out, it is necessary to replace a block head. 17. Check up backlashes between directing plugs and valves as follows:       – Insert the valve into directing plug so that the end face of its core has appeared заподлицо with a plug end face. It is necessary to insert that valve which will be established in this plug;       – Fix the indicator so that its leg rested against a valve plate, as is shown in fig. backlash Measurement between the valve and the directing plug. Press the valve towards the indicator against the stop and establish in this position the indicator on a zero. Then move the valve to an opposite side against the stop and define on the indicator size of moving of the valve. The maximum permissible size of moving of the valve for petrol engines makes 0,5 mm for the inlet valve and 0,6 mm – for final; for diesel engines – 1,3 mm for inlet and final valves. If the measured size exceeds the specified sizes, it is necessary to repeat measurement with the new valve; if again exceeds, replace a block head. 18. Check up an axial backlash of a camshaft. For this purpose at petrol engines of 1,4 l, 55 and 74 kw:       – Place camshafts 27 (fig. of the Detail of a head of the block of cylinders of engines of 1,4 l, 55 and 74 kw) in the case of 5 bearings see and establish back covers 7 and 11, having tightened bolts of 8 their fastenings by the moment 10 Нм;       – Fix the indicator so that its leg rested against a camshaft end face, as is shown in fig. Measurement of an axial backlash of a camshaft. Move a camshaft towards the indicator against the stop and in this position establish the indicator on a zero. Then move a camshaft in an opposite side against the stop – the indicator will show size of an axial backlash. 19. In the same way measure an axial backlash of other camshaft. The axial backlash at diesel engines is measured similarly, but their camshaft is established in a block head (at the removed hydropushers of valves) and fixed by covers of the first, third and fifth bearings. The axial backlash for all engines should not exceed 0,15 mm.

The sizes of valves

The engine	The inlet / final valve
	Diameter Plates and, mm	Diameter Core b, mm	Length The valve with, mm
Petrol 1,0 l, 37 kw	34,0/27,0	7,0/7,0	104,0/104,0
Petrol 1,4 l, 50 kw	34,0/30,0	7,0/7,0	101,0/101,0
Petrol 1,4 l, 55 and 74 kw	29,5/26,0	5,973/5,953	100,9/100,5
Diesel 1,9 l, 74 kw	35,95/31,45	6,980/6,956	89,95/89,95

The sizes of saddles of valves

The engine	The size	The inlet valve	The final valve
Petrol 1,0 l, 37 kw	Diameter of a saddle of the valve, mm	33,4 0,1	26,4 0,1
	Width of a working facet, mm	1,3 – 1,6	1,3 – 1,6
Petrol 1,4 l, 50 kw	Diameter of a saddle of the valve, mm	32,9 0,1	29,6 0,1
	Width of a working facet, mm	1,45 – 1,75	1,65 – 1,95

Maximum permissible выступание valves

The engine	The inlet valve	The final valve
1,0 l, 37 kw	43,1 mm	43,0 mm
1,4 l, 50 kw	42,7 mm	42,8 mm