Renault Megane, Scenic

Since 1996 of release

Repair and car operation

Cleaning, survey and service of a head of the block of cylinders and valves

Full cleaning of components of a head of the block of cylinders and valves with the subsequent detailed survey will allow you to define, what procedures are necessary for executing during an engine partition.

CLEANING

1. Remove from a head of the block of cylinders all traces of an old lining. 2. Clean off from chambers of combustion and apertures a deposit, then carefully wash out a head of the block of cylinders kerosene or suitable solvent. 3. Scratch out from valves the basic part of a deposit, then by means of a wire brush remove from heads and rods of valves its rests. 4. On engines F8Q, vortical chambers are necessary for removing, if they freely sit (note an arrangement of chambers so that they could be established on a former place) (address to an accompanying illustration). 5. If the head is extremely polluted, it it is necessary to clear the ferry. Be in summary convinced that all lubricant apertures and lubricant channels are cleared.

Execute all procedures of survey before to draw a conclusion that is necessary to address in automobile repair shop for a repoint. Make the list of all components demanding processing.

HEAD OF THE BLOCK OF CYLINDERS

SURVEY AND SERVICE

1. Attentively examine a head on presence of cracks and other damages, and also smudges of a cooling liquid. At detection of cracks, replace a head. 2a. By means of an edge of a ruler and probeа check up a surface of a head of the block of cylinders on deformation. On engines F8Q watch, that the edge of a ruler did not pass on vortical chambers as they can act over a landing surface of a head of the block of cylinders. If deformation exceeds the limit specified in Specifications, to grind a surface the manufacturer does not recommend, and a unique exit - to replace a head of the block of cylinders. 2b. Check up, that the full height of a head of the block of cylinders corresponded to the value specified in Specifications (address to illustrations). 3. Examine saddles of all valves. If they are strongly expressed by dot corrosion, have burst or have burnt through, charge to the expert переточить them. If dot corrosion is insignificant, it can be removed polishing of a head and a saddle of the valve special fine-grained paste as is described more low. Pay attention that on diesel engines of a saddle of valves it is possible to grind off only on the limited depth to avoid compression reduction. By means of a micrometer be convinced that depth of the valve below a landing surface of a head of the block of cylinders in the limits presented in Specifications in the Part From the current Chapter (address to an accompanying illustration). 4. If directing plugs of valves are worn out (the valve moves on a horizontal axis), replace the directing. For definition of lateral moving of the valve it is possible to use a micrometer. Establish in directing the new valve and check up its lateral люфт to define, whether the valve or the directing is worn out. If it is necessary to establish new directing, valves also should be replaced. It is better to charge this work to the expert as at its skilful performance there is a risk of damage of a head of the block of cylinders. 5a. On engines F8Q, examine a condition of vortical chambers that on them there were no burnt through places or cracks. If it is required, it is possible to replace chambers. 5b. By means of a micrometer check up, that vortical chambers did not act from a head more than is specified in Specifications. Establish on a zero a micrometer on a surface of a head of the block of cylinders, then measure выступание the vortical chamber (address to illustrations). 6. Where it is applied, check up on presence of signs of deterioration seats of pushers in a head of the block of cylinders. If there is an excessive deterioration, it is necessary to replace a head of the block of cylinders. 7. Examine working surfaces of bearings of a cam-shaft in a head of the block of cylinders (and covers / fixing elements of bearings where are applied). In case of deterioration it is necessary to replace a head.

VALVES

SURVEY AND SERVICE

1. Examine a head of each valve on presence of the dot corrosion, the burnt through places, cracks and signs of the general deterioration. Check up a valve rod on presence of scratches and the developed places. Rotate the valve and examine it on presence of signs of deformation. Examine an end face of each rod on presence of dot corrosion and signs of excessive deterioration. If the valve condition seems satisfactory, measure diameter of a rod in several places by means of a micrometer (address to an accompanying illustration). Any essential distinction of the received data specifies in deterioration of a rod of the valve so it is necessary to replace the valve. If valves are not damaged, they should be ground in to provide dense прилегание to saddles. 2. Grinding in of valves is carried out as follows. Turn a head of the block of cylinders, having enclosed wooden бруски under each end to provide a backlash for rods of valves. 3. Put paste for grinding in of a corresponding grade on a surface of a saddle of the valve and attach to a valve head a special sucker. Rotating the valve there-here on a half-turn, grind its head, grinding in it to a saddle, sometimes lifting the valve to redistribute paste (address to an accompanying illustration). Installation under a head of the valve of a weak spring considerably will facilitate work. If rough grinding paste is used, work while contact surfaces of a saddle and the valve do not become dim, matte, then erase structure and repeat process with fine-grained paste. When saddle and valve surfaces will get equal light grey colour, grinding in will be considered as the finished. Do not grind in valves longer, than it is necessary, it will lead to undesirable deepening of a saddle in a head of the block of cylinders. When all valves will be ground in, is accurate смойте all traces of grinding paste, using kerosene or suitable solvent.

VALVE COMPONENTS

SURVEY AND SERVICE

1. Examine springs of valves on signs of damages and colour change, and also measure their free length by means of a ruler (address to an accompanying illustration), or compare to a new spring. 2. Put each spring on an equal surface and check up them on deformation by means of a corner. If any of springs it is damaged, deformed or ослабла, get a new full set of springs. It is recommended to replace springs after their each removal during engine major repairs, irrespective of their condition. 3. Where it is applied, check up pushers and adjusting washers on presence of scratches, corrosion (especially on washers) and deterioration. Replace all components as required.

COMPONENTS КОРОМЫСЛА - ENGINES E7J AND К7М

SURVEY AND SERVICE

1. Check up contact surfaces коромысел that on them there were no holes, scratches or other signs of deterioration. Disassemble an axis коромысел, and in the same way check up коромысла, rotary axes and contact surfaces. Measure internal diameter of everyone коромысла and check up them on placing on a shaft. Clean oil channels in everyone коромысле, using a wire piece. Replace коромысла or axes if it is necessary.

МАСЛООТРАЖАТЕЛЬНЫЕ CAPS

SURVEY AND SERVICE

1. It is necessary to replace maslootrazhatelnye caps after their each removal.