Piston rings Suzuki SX4 I

Piston rings

To measure end gap, insert piston ring (2) into cylinder bore and then measure the gap by using thickness gauge (1). If measured gap is out of specification, replace ring.

Note. Clean carbon and any other dirt from top of cylinder bore before inserting piston ring.

Piston ring end gap

PISTON RING END GAP SPECIFICATION

Piston rings end gap

"a": 120 mm (4.72 in.)

Scheme 177

Scheme 178

Scheme 179

1. Big-end side clearance: Check big-end of connecting rod for side clearance, with rod fitted and connected to its crank pin in the normal manner. If measured clearance is found to exceed its limit, replace connecting rod. Big-end side clearance BIG-END SIDE CLEARANCE SPECIFICATION Standard Limit 0.25 - 0.40 mm (0.0099 - 0.0150 in.) 0.45 mm (0.0177 in.)
2. Connecting rod alignment: Mount connecting rod on aligner to check it for bow and twist. If limit is exceeded, replace it. Limit on bow 0.05 mm (0.0020 in.) Limit on twist 0.10 mm (0.0039 in.)

Scheme 180

Scheme 181

Scheme 182

Scheme 183

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Scheme 185

Scheme 186

Scheme 187

Scheme 188

1. Inspect crank pin for uneven wear or damage. Measure crank pin for out-of-round or taper with a micrometer. If crank pin is damaged, or out-of round or taper is out of limit, replace crankshaft or regrind crank pin. Connecting rod bearing and crank pin CONNECTING ROD BEARING AND CRANK PIN SPECIFICATION Item Standard Crank pin diameter 49.982 - 50.000 mm (1.9768 - 1.9685 in.) Out-of-round "A"-"B" Taper "a"-"b" Out-of-round and taper limits 0.01 mm (0.0004 in.)
2. Connecting rod bearing general information: Inspect bearing shells for signs of fusion, pitting, burn or flaking and observe contact pattern. Bearing shells found in defective condition must be replaced. Two kinds of connecting rod bearings are available; standard size bearing and 0.25 mm (0.0098 in.) undersize bearing. For identification of undersize bearing, it is painted red (1) at the position as indicated in (Scheme 182), undersize bearing thickness is 1.605 - 1.615 mm (0.0632 - 0.0635 in.) at the center of it.
3. Connecting rod bearing clearance: Before checking bearing clearance, clean bearing and crank pin. Install bearing in connecting rod and bearing cap. Place a piece of gauging plastic (1) to full width of crank pin as contacted by bearing (parallel to crankshaft), avoiding oil hole. Install connecting rod bearing cap (1) as follows. Point arrow mark (2) on cap to crankshaft pulley side. Apply engine oil to connecting rod bolts (3). Tighten all connecting rod bolts to 15 N.m (1.5 kgf-m, 11.0 lb-ft). Retighten them by turning through 45°. Repeat step d once again. Tightening torque Connecting rod bolt a: Tighten 15 N.m (1.5 kgf-m, 11.0 lb-ft), 45° and 45° by the specified procedure NOTE: Do not turn crankshaft with gauging plastic installed. Remove connecting rod bearing cap, and using a scale (2) on gauging plastic envelope, measure gauging plastic (1) width at the widest point (clearance). If clearance exceeds its limit, select connecting rod bearing by referring to «PISTONS, PISTON RINGS, CONNECTING RODS AND CYLINDERS INSPECTION AND CLEANING»(ref-268922-S38657426232007102700000) below mentioned item. After selecting new bearing, recheck clearance. Bearing clearance BEARING CLEARANCE SPECIFICATION Standard Limit 0.045 - 0.063 mm (0.0018 - 0.0025 in.) 0.08 mm (0.0031 in.) If clearance can not be brought to within its limit even by using a new standard size bearing, replace crankshaft or regrind crankpin to undersize as follows. Install 0.25 mm undersize bearing to connecting rod big end. Measure bore diameter of connecting rod big end. Regrind crankpin to the following finished diameter. Finished crankpin diameter = Measured big end bore diameter (including undersize bearing) - 0.054 mm (0.0021 in.) Confirm that bearing clearance is within the standard value. NOTE: After checking the connecting rod bearing clearance, make sure to check for "Connecting rod bolt" under «PISTONS, PISTON RINGS, CONNECTING RODS AND CYLINDERS INSPECTION AND CLEANING»(ref-268922-S38657426232007102700000).
4. Selection of connecting rod bearings: NOTE: If bearing is in malcondition or bearing clearance is out of specification, select a new standard bearing according to the following procedure and install it. When replacing crankshaft or connecting rod and its bearing due to any reason, select new standard bearings to be installed by referring to numbers stamped on connecting rod and its cap and/or alphabets stamped on crank web of No. 3 cylinder. Check stamped numbers on connecting rod and its cap (Scheme 186) Three kinds of numbers ("1", "2" and "3") represent the following connecting rod big end inside diameters. For example, stamped number "1" indicates that corresponding connecting rod big-end inside diameter is 53.0000 - 53.0060 mm (2.0867 - 2.0868 in.). Connecting rod big-end inside diameter CONNECTING ROD BIG-END INSIDE DIAMETER Stamped numbers Connecting rod big-end inside diameter 1 53.0000 - 53.0060 mm (2.0867 - 2.0868 in.) 2 53.0061 - 53.0120 mm (2.0869 - 2.0870 in.) 3 53.0121 - 53.0180 mm (2.0871 - 2.0873 in.) Next, check crank pin diameter. On crank web of No. 3 cylinder, four alphabets are stamped (Scheme 187) Three kinds of alphabet ("A", "B" and "C") represent the following crank pin diameter respectively. For example, stamped "A" indicates that corresponding crank pin diameter is 49.9940 - 50.0000 mm (1.9683 - 1.9685 in.). Crank pin diameter CRANK PIN DIAMETER Stamped alphabet Crank pin diameter (without bearing) A 49.9940 - 50.0000 mm (1.9683 - 1.9685 in.) B 49.9880 - 49.9939 mm (1.9681 - 1.9682 in.) C 49.9820 - 49.9879 mm (1.9677 - 1.9680 in.) There are 5 kinds of standard bearings differing in thickness. To distinguish them, they are painted in the following colors at the position as indicated in (Scheme 188). Each color indicated the following thickness at the center of bearing. Standard size of connecting rod bearing thickness STANDARD SIZE OF CONNECTING ROD BEARING THICKNESS SPECIFICATION Color painted Bearing thickness Green 1.482 - 1.485 mm (0.05835 - 0.05846 in.) Black 1.485 - 1.488 mm (0.05847 - 0.05858 in.) Colorless 1.488 - 1.491 mm (0.05859 - 0.05870 in.) Yellow 1.491 - 1.494 mm (0.05871 - 0.05881 in.) Blue 1.494 - 1.497 mm (0.05882 - 0.05893 in.) From number stamped on connecting rod and its cap and alphabet stamped on crank web No. 3 cylinder, determine new standard bearing to be installed to connecting rod big-end inside, by referring to «SPECIFICATIONS OF STANDARD CONNECTING ROD BEARING SIZE TABLE»(ref-268922-S40603732372007102700000). For example, if number stamped on connecting rod and its cap is "1" and alphabet stamped on crank web No. 3 cylinder is "B", install a new standard bearing painted in "Black" to its connecting rod big-end inside. Specifications of new standard connecting rod bearing size SPECIFICATIONS OF STANDARD CONNECTING ROD BEARING SIZE TABLE Number stamped on connecting rod and its cap (Connecting rod big end inside diameter) 1 2 3 Alphabet stamped on crank web of No. 3 cylinder (Crank pin diameter) A Green Black Colorless B Black Colorless Yellow C Colorless Yellow Blue Check bearing clearance with newly selected standard bearing by referring to «CRANK PIN AND CONNECTING ROD BEARINGS»(ref-268922-S10152393602007102700000). If clearance still exceeds its limit, use next thicker bearing and recheck clearance.
5. Connecting rod bolt Measure each thread diameter of connecting rod bolts (1) at "A" on 28.5 mm (1.12 in.) from bolt mounting surface and "B" on 42.0 mm (1.65 in.) from bolt mounting surface by using a micrometer (2). Calculate difference in diameters ("A"-"B"). If it exceeds limit, replace connecting rod. Connecting rod bolt measurement points "a": 28.5 mm (1.12 in.) "b": 42.0 mm (1.65 in.) Connecting rod bolt diameter difference limit ("A"-"B"): 0.1 mm (0.004 in.)

Clean carbon from piston head and ring grooves, using a suitable tool.

Scheme 189

1. Disconnect negative (-) cable at battery.
2. Drain engine coolant.
3. Remove exhaust manifold cover.
4. Remove engine block heater (1).