Cylinder Taper and Cylinder Out of Round

Cylinder Taper and Cylinder Out of RoundAditya PatelEquipment UtilizedAn medley of hand tools, pullers and specialty measuring tools were used during this assignmentHealth and Safety PrecautionsSafety boots and glasses were mandatory in the shopProper lifting techniques, and getting inspection and repair lifting was very importantUnit IdentificationGM 3100 EngineReferencesGM 3100 service manual, and our classroom text book were used. Lab notes and internet were used for near of the notes. system1. List solely the steps needed to note piston chamber taper and out of round.a bore quality calibration unit was baffle up by using fixture and calibration unitthe bore gauge was entrustd in this unit and calibrated using the micrometre scale on the unit. To calibrate for specific bore, use the standards. For example, for 4.406 bore, install 4.000+ standard and set the scale to 0.406. Bore gauge is calibrated until the dial shows 0 on it. Or more than adjustment should be done.the bo re gauge was then placed inside the cylinder at Top gormandise surface and rock the bore gauge front and back until dial goes up and comes back. Note the highest reading, the dial reaches. Do same for bottom thrust surface.To measure the cylinder out of round, measure purloin thrust surface of the cylinder but perpendicular to the first heedful.Now compare both reading for top thrust surfaces readings. If the difference between the metric reading is more than 0.0005 then the cylinder is out of round or else, it is good.To measure the taper, subtract the reading of bottom thrust surface from top thrust surface. If the reading is more than 0.0008 then cylinder is not good.Cylinder Taper is the difference of the diameter between top of the cylinder bore under the rooftree and bottom of the cylinderCylinder out of Round is the difference of diameter when mensural parallel to crankshaft and then perpendicular to the same at top of the cylinder using bore gauge.Method Continued 2. Document 2 methods of measuring piston to cylinder bore clearance.Feeler Strip Method off all compression and embrocate control rings from pistonsInvert the piston and place it back in the cylinder in upside down position with advance strip. The advance strip should not be on the piston pin hole. After piston is placed in the cylinder easy take the filler gauge out. While victorious the filler gauge out, if it feels too laborious or loose the try different size of the gauge until you get the gross(a) size. The perfect size of filler gauge should not feel too tight or smooth while taking it out.(Measuring clearance using feeler strip)Calculated MethodMeasure the diameter of the piston across the skirt with well calibrated micrometre. Note the reading.Now using the bore gauge measure the cylinder diameter under the ridge. Record the reading.Now subtract the piston diameter from cylinder diameter. The measurement achieved is the piston to cylinder clearance.Note that before tak ing any reading the micrometre should be well calibrated and the surfaces should be cleaned.(Bore gauge measuring the cylinder diameter)(Measuring piston diameter using Micrometre)3. Construct a graph listing cylinder, piston ring and crankshaft clearances.Located under observations heading4. Record how to check ring clearances. (side and end)Side ClearanceRemove all compression and oil control rings from pistonsClean the piston ring groove before measuring.For measuring the ring clearance, the ring doesnt need to be installed in the piston. Gently place the ring in the groove. After placing the ring measure the clearance with the help of feeler gauge between the ring and upper edge of the groove.Compare the measured ring clearance with the manufacturers specification. If the measured clearance is more then the manufacturers specification the change the ring.(Measuring lot Clearance using Feeler Strip)End GapRemove all compression and oil control rings from pistonsPlace the ring in the same cylinder from which piston come out.Using the piston slowly push the ring in the cylinder. Then measure the gap between the two ends of the rings with filler strip.The filler strip should not too hard or too smooth to pass between the two ends of the rings.Then do same for the second ring and note the measurement. Compare this measurement with the manufacturers specification.If the measured end gap is more then the actual specification the change the ring.(Measuring piston ring end gap using feeler strip)5. Describe 2 methods of measuring crankshaft bearing clearance.Plastigauge Methodremove the main bearing caps from the block and clean the surface of the crankshaft journals with a clean rag.Now place a flip of plastigauge according to the width of the journal. ground back main bearing caps on their same position as before.Check that the bearings are in the correct direction.Install the bolts and tighten them with torque wrench at the manufacturers specification.Now remo ve the main bearing caps and check the spread of plastigauge.Compare with the marking given on the retain of the plastigauge and note the reading.Now compare this reading with the actual specification.Before installing main bearings back, carefully wipe the plastigauge marks.(Measuring the Crankshaft bearing clearance using plasti gauge)Calculated MethodMeasure the crankshaft journal diameter using a well calibrated micrometre. Measure every journal two times both perpendicular at each other. Note every reading.Now put the bearing journals back on. Use torque wrench to tight the bearings with specified torque. Using inside micrometre or bore dial gauge measure the diameter of the bearing. Note the reading.To measure bearing clearance, subtract the crankshaft journal diameter measurement from bearing journal diameter.The permissible clearance for crankshaft is between 0.0008-0.0025.6. Explain what causes cylinder taper and cylinder out of roundCylinder Taper is caused by wear caused by friction and conflagration cause the bore to be cone shaped.Cylinder Out of Round is caused by pressure created by piston rings to the cylinder walls.ObservationsCylinderMeasurementsCyl 1Cyl 2Cyl 3Cyl 4Cyl 5Cyl 6(Thrust Surface under(a) Ridge) A0.00160.00180.00180.00150.00150.0014(Thrust Surface Bottom) B0.00130.00140.00120.00140.00110.0013(90 Under Ridge) C0.00120.00150.00120.00130.0010.0011Taper ( reckon B from A)MeasurementsCyl 1Cyl 2Cyl 3Cyl 4Cyl 5Cyl 6(Thrust Surface Under Ridge) A0.00160.00180.00180.00150.00150.0014(Thrust Surface Bottom) B0.00130.00140.00120.00140.00110.0013Taper0.00030.00040.00060.00010.00040.0001Specification0.0008Out of Round ( Subtract C from A )MeasurementsCyl 1Cyl 2Cyl 3Cyl 4Cyl 5Cyl 6( Thrust Surface Under Ridge ) A0.00160.00180.00180.00150.00150.0014( 90 Under Ridge ) C0.00120.00150.00120.00130.00100.0011Out of Round0.00040.00030.00060.00020.00050.0003Specification0.0005Observations ContinuedPiston Ring ClearanceMeasurementsSpecs123456 Ring End GapTop Ring0.006-0.0140.240.240.240.270.170.19Second Ring0.0197-0.02800.300.160.200.180.160.19Ring Groove ClearanceTop Ring0.002-0.00330.0020.00250.0020.0020.0020.002Second Ring0.002-0.00350.0020.0020.00250.0020.0020.002Bearing ClearanceChecksSpecs1234Bearing Bore Dia. (A)2.6472 2.65022.6492.6522.6482.650Journal Diameter (B)2.6473 2.64832.6472.6462.6472.645Clearance (A B)0.0008 0.00250.0020.0060.0010.005Plastigauge Clearance0.0008-0.00250.00150.00200.00100.0020ConclusionsUpon completing the measurements and optical inspections, I would recommend that due to the excessive wear and out of round cylinder, the cylinder should be bored. While measuring the piston ring clearance we notice that the piton rings were replaced and were both of same size on one piston.