One, the operating environment should be dust-proof, wind-proof, the operation should be standardized
Some motorcycle repair stores overhaul the engine are operated outdoors, they do not care about how much wind and dust, just focus on the head of the replacement. The new oil in this environment may be dirtier than the old one, and the overhaul of the engine must be carried out indoors. In addition, the operation must also be standardized, the demolition of the demolition, should not move do not move. Such as changing CC125 gear cam and fork, the left side of the engine box does not have to open, the crankshaft does not have to be removed, you can change and repair the gear mechanism. If the misoperation will cause unnecessary trouble, not only misuse of time, but also may cause the side box sealing bad. Fix the engine prerequisite is to know it like the back of your hand, carefully comprehend the engine parts structure.
Second, the engine shell cleaning before dismantling is indispensable
Overhaul of the engine shell has a lot of oil and dust accumulation, if not cleaned up in a timely manner, these impurities will be in the dismantling of the engine mixed into the internal body, after loading the machine, the relevant parts to bring unnecessary wear and tear. Again, foreign matter falling into the engine, change will block the oil channel, and will lead to poor lubrication, resulting in holding cylinder, holding shaft, clutch sintering, and so on. In addition, without cleaning the engine casing, in the box, foreign objects will be stuck in the box combination, affecting the seal, resulting in oil seepage, oil leakage. Cleaning the engine casing can also prevent the oil sludge from covering the bolts, so as not to miss the removal. Such as Chongqing 80 engine in the case of fixed bolts, there are two very easy to be covered by oil sludge, if the leakage, forcibly dismantle the case, will damage the engine case.
Three, do a good job marking is very important
Both mature models, or transition models, motorcycle engine varieties, structural characteristics of different. When we decompose a variety of engines, we should do a good job of installing a variety of accessories marking, some of the nuts buckle is the same, but the appearance is very different, should be well marked, can not be installed arbitrarily, because a variety of nuts have a certain torque requirements, a variety of shapes are determined after many tests, there is a certain scientific basis, if interchangeable, it will affect the fixed effect, triggering new failures. Such as CG125 clutch fixing nut and crankshaft right end oil filter nut with the same internal thread, interchangeable, although it can be mounted, but the two shapes are different, torque is different, the clutch fixing nut than the crankshaft fixing nut torque is much larger. When we dismantle the engine of less familiar models, such as CB125T, CBR400, etc., more should be marked in the dismantled parts, in order to prevent misinstallation, omission.
Four, the use of special tools, special utensils
The use of tools directly affects the quality and efficiency of repair work. Specialized tools are designed for the maintenance of prescribed parts, scientific and easy to use, labor-saving, not hurt parts, such as fear of trouble, trying to save money, just take a tool to violate the operation will make the quality of work greatly reduced. Such as, dismantle the GY6 machine after the clutch retaining nut should be 19 # socket wrench with the brake can be smoothly removed, visible some maintenance stores do not have a special tool, casually take a steel punch barbaric dismantling, the nut is removed, deformed nut how can be tightened again according to the specified torque? If the clutch nut is loosened over time, the clutch assembly will fall off, and the consequences will be unimaginable. There was a motorcyclist's motorcycle overhaul soon after the clutch dislodged to the side box rupture. Irregular operation can also damage the bearing of the inner end of the output shaft.
In addition, when we dismantle the engine, should be cleaned before and after the parts in order to be placed in a special aluminum plate or wooden plate, can not be stacked everywhere, some very small parts are very easy to lose, such as the crankshaft half-round key, piston pin retaining ring, a variety of card spring gaskets positioning pins and so on.
Fifth, the parts of the order of placement
Decomposition of unfamiliar engine, according to the sequential order of placement of the parts, to prevent leakage, misinstallation. Such as the car engine gear mechanism, in the replacement of broken parts, according to the left to right to decompose the parts one by one, replace the new product assembly in the reverse order, so as not to cause errors.
Six, related parts of the cleanup is very critical
Engine once disassembled, the gaskets (paper, asbestos and other gaskets) will be used to promote the elasticity, promote the sealing effect, can not be used again, should be completely eradicated to replace the new product. Furthermore, no gasket sealing parts to use bamboo tablets will fail to carefully remove the sealant (DX100, AX100, K100 and other two-stroke engines in the box), and then, uniformly coated with genuine special sealant box fastening. Demolition of the pieces and parts with the gap of the sludge, grinding application of bamboo thoroughly removed, such as CG125 oil filter, C100 clutch in the hard debris. This work also determines the use of the engine after overhauling the order. Some repairers only replace the damaged parts, do not replace the fatigue of the oil seals, gaskets, card springs, and do not clean the machine oil sludge, impurities, mounted on the shelf, the car can be ridden, but not for a long time, the new faults will appear.
Seven, replacement parts to be carefully measured, compared
Parts market mixed, in order to ensure the quality of maintenance, in the purchase of genuine products at the same time but also to the old parts and new parts of the new carefully compared to the use of special tools for the actual measurement of the overhaul of the engine is required to be intact as in the first place. Such as the replacement of the crankshaft, cylinder components and other parts, to use vernier calipers to measure the crankshaft assembly parts are standard, measuring cylinder plug ring is a tight fit, to avoid the parts installed after the test drive only to find faults, time-consuming and waste of labor.
Eight, the assembly of parts lubricant coating is indispensable
Assembly of the disassembled parts to take the appropriate amount of new lubricant evenly coated in the combination of parts, such as the crankshaft and bearings, gear cams and box, gears and gears, cylinder plugs ring and other pieces of pieces between the lubricating oil will be smoother assembly, in order to facilitate the tight box, to avoid assembling the parts of the drying of the astringent, difficult to close the box to avoid damaging the machine parts.
Nine, the selection of standard gaskets, careful use of sealant
assembly of the engine, the selection of new gaskets can not be ignored, if the selection of non-standard gaskets, will cause oil leakage, startup difficulties (two-stroke car intake leakage, resulting in a mixture of dilute, and therefore difficult to start the car), or even worse, will cause the oil circuit is blocked, triggered by a new failure. Especially on the cylinder gasket, strict requirements, inferior products are very easy to burn through, the use of asbestos can not be used aluminum gasket, too thick will also affect the compression ratio, to the vehicle is difficult to start, driving powerless. In addition, but also pay attention to the gum gasket, sealing ring can not be missed, such as CY80, DX100, AX100 crankshaft on the rubber ring, carburetor interface on the rubber ring. Sealant in the engine assembly use very little, only in the two-stroke car in the box assembly, CB machine cylinder head will be used, four-stroke engine assembly generally a drop of sealant also do not have to apply, such as C100, CG125, CG150, GY6 and other machines on the combination of gaskets, rubber ring can be sealed very well. Coated with sealant is conducive to sealing, but more sealant will also block the oil circuit, triggering new failures. If there is a rubber ring in the combination of coated sealant, will cause the rubber ring is sticky, push the loss of sealing effect, such as CG125, GY6 cylinder head.
Ten, pay attention to the replacement of oil seals
Engine overhaul, after disassembly of the various related oil seals, there will be varying degrees of operation, should be appropriate to replace the new product, to prevent the oil leakage or mixture leakage, resulting in starting difficulties. Individual large-displacement motorcycles or shaped motorcycle oil seal purchase difficulties, if the original oil seal operation is not large, you can remove the spring of the oil seal lip, cut about 5mm, you can use as usual.
Eleven, accessories replacement should be installed while debugging
Replacement of damaged parts to standardize the operation, correct installation, good debugging, to prevent problems before they occur. Such as the replacement of C100 starter shaft, remove the shaft before, with a hacksaw blade in the case of a good start gear position marking, after the installation of the new starter shaft, to close the box to try to start (not only to start the smooth, but also requires the start back to the start of the gears and gears do not impede each other), and then on the tightening of the fixed bolts, and at the same time should be tried to change the transmission of all gears whether the changes in the free and clear, the oil pump shaft in place in order to avoid the emergence of a new The faults.
Twelve, do a good job of waterproofing
Wire harnesses connected to the engine should be plugged into place, waterproof, rainproof work. After the engine is installed on the frame, the wiring harness should be straightened out, the plug can not be missed, to ensure that the lighting charging line works properly. In addition, the waterproof cover should be installed firmly, the harness card firmly, no waterproof cover should be waterproof tape wrapped tightly.
Thirteen, pay attention to safe atmospheric balance hole hose
Have seen a number of overhauled motorcycles, the atmospheric balance hole hose leakage, day long, the balance hole is blocked by foreign objects, resulting in high internal engine temperature, driving powerless, no high-speed phenomenon. In addition, the hose folding, stuck in the big frame, will also cause the above phenomenon.
Fourteen, beware of two-stroke motorcycle oil pipe off or blocked by foreign objects
After the engine is removed, the oil pipe should be plugged in time with a clean 6 # bolt to prevent dust and other foreign objects from entering. When installing the engine, the oil pipe should be straightened out to prevent jamming, and both ends should be fixed with card springs, so as to prevent new failures caused by dislodging.
Fifteen, the engine and the big frame connected to the hitch wire should be installed firmly
Generally on electric motorcycles, there is a thick hitch wire between the engine and the big frame, both ends must be on the real, to avoid false connecting, otherwise, it will result in the starter motor to work weakly, starting difficulties.
Sixteen, the engine fixed parts can not be missed after a number of overhaul of the motorcycle engine, fixed parts are not less, or lack of that, for example: the engine and the frame of the flexible combination of steel rubber combination of missing set, will cause the engine * * * vibration, the driver feels very uncomfortable, and even cause a dangerous driving. Chongqing 80, Jetta 100, Jincheng 90, etc., are this structure. In addition, the leakage of the engine fixing bolt on the flat pad and spring spacer, over time, will cause the engine to loosen, affecting driving safety.
Comments | 1 0
Report | 2013-06-18 13:35 enthusiasts
Two-stroke engine, the most critical maintenance is the combustion of two-stroke special oil oil quality must be good, and to ensure that the right amount of oil mixing, the amount of oil is too large prone to carbon, the amount of oil is too small prone to increase the wear of the cylinder block, the piston and the ring and the bearings, and the rest. There is no big difference with the four-stroke engine.