Fault Finding Guide

Failure Analysis
       1), turbocharger test
      What kind of supercharger is good supercharger? First ,The supercharger is qualified goods or not, first we should look at the turbocharger nameplate on the assembly, the customer is matching with diesel engine, then check the turbocharger rotor rotation is flexible or not, axial gap and radial gap whether is in the specified range. Specific standards are as follows: A, axial clearance should be in 0.069 ~ 0.131mm; B, radial clearance can be a convenient and valid measurement method : the compressor impeller ( aluminum shell at the impeller) to pressure shell side to side, measuring the radial gap should be less than 0.15mm; the supercharger is qualified.
       2), several false analysis of turbocharger oil leakage
      First, pressure shell exports as oil and gas accumulation caused by the supercharger air compressor end leakage: first should check the turbocharger; confirm the supercharger is qualified, can generally be from the turbocharger using situation analysis, such as the use of the environment caused by dust, air filter clog caused by negative pressure more than 5.5kPa, which will cause the supercharger air compressor end leakage; cars on the mountain slope, diesel and gas door at low speed for 15 minutes or more, supercharger impeller back pressure has not established a gas seal forming a vacuum can also cause the supercharger air compressor end leakage. As long as the regular maintenance of air filter, diesel engine idling time not too long, the false oil leakage phenomenon can be eliminated. If the environment construction running state can not change, as long as the regular removal of air filter dust, removing turbocharger pressure shell outlet and a pressure shell oil export pipeline, the false oil does not affect the normal use of the diesel engine.
      The oil pressure too high, will cause the turbocharger oil leakage: supercharger oil inlet pressure turbocharger oil leakage is caused by one of the reasons. When we confirmed the supercharger is qualified, and found the diesel engine oil pressure is much higher than manual provisions, should check the diesel engine lubrication system, pressure regulating valve is stuck or malfunction, diesel engine oil pressure is normal, the turbocharger oil leakage can be ruled out.
      The oil return not free would cause the turbocharger oil leakage: supercharger oil return by gravity from the supercharger oil return pipe return to the engine, if the oil return pipe shrinkage Festival and obstruction, the supercharger oil return not free, turbocharger will appear at both ends of leaking engine oil. Should be excluded from the return oil free, the supercharger in good condition, fault is excluded.
      The diesel engine in construction, stop and start, would cause the supercharger intermediate casing turbine end coking; at the same time causes the intermediate shell oil return chamber of coke, the supercharger oil return cavity narrow oil return not free to produce oil leakage, in this case you should check the wearing parts are intact, and removal of coking, the work must be carried on by the professional personnel.
      Finally, diesel blowby would cause the major supercharger oil return not free, turbocharger oil leakage: some turbocharger oil leakage was found even ends, by checking the supercharger is qualified, the oil return to normal, and then dismantled and found the supercharger spindle in the middle ( two floating bearings between ) have very thick grease some hard to eradicate, found after cleaning spindle middle pale yellow and supercharger oil return pipe is also the oil dirt, from the above phenomenon can be judged for the diesel blowby caused a supercharger oil return. Replacement of diesel engine four supporting exclusion of diesel engine under gas channeling, the supercharger oil return pipe, cleaning, fault can be ruled out
      3), turbocharger using requirements
      Because the supercharger is work in the high speed and high temperature, correctly use and fuel requirements are very strict, we must use the diesel engine manufacturers specified oil, must not to mess with, when the turbocharger damage caused by oil spill, must identify the damage cause and elimination for turbocharger, if don't find reasons.Will replace supercharger will appear with a same fault, in brief analysis of supercharger failure is a systematic work, do not settle rashly, changed.