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Remove/Install Piston Rings - AR03.10-P-7311MFC

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Engine 260 in model 118, 177, 247 

G16048190Courtesy of MERCEDES-BENZ USA
CAUTION Risk of injury  caused by scraping or cutting body parts on sharp vehicle parts Always wear protective gloves when working on or near sharp and non-deburred vehicle parts.
Deburr repair panels.
AS00.00-Z-0017-01A
CAUTION Risk of injury  to skin and eyes due to handling of engine oil. Risk of poisoning  caused by swallowing engine oil Wear protective gloves, protective clothing and safety glasses.
Do not fill engine oil into beverage containers.
AS18.00-Z-0001-01A
Topical note  Notes on avoiding damage through contamination and foreign objects   AH00.00-P-5000-01A
REMOVING Remove     
1 Remove pistons (5).   AR03.10-P-7021MFC 
2 Measure side clearance of the piston rings (6a, 6b, 6c).   AR03.10-P-7311-01MFC 
    Piston ring vertical clearance *BE03.10-P-1001-05L 
3 Remove piston ring (plain compression ring) (6c) with piston ring pliers. SPECIAL TOOL Pliers Fig 1
4 Remove piston ring (taper-faced hook scraper ring) (6b) with piston ring pliers. SPECIAL TOOL Pliers Fig 1
5 Manually remove piston ring (oil scraper ring) (6a).    
6 Clean piston rings (6a, 6b, 6c) and piston ring grooves. Assembly cleaner *BR00.45-Z-1028-04A 
7 Check crankcase, crankshaft, pistons (5) and connecting rods for damage and wear. If wear or damage is detected.
Replace the affected component.
 
8 Measure end gap of the piston rings (6a, 6b, 6c).   AR03.10-P-7311-02MFC 
    Piston ring end gap *BE03.10-P-1002-05L 
INSTALLING Install     
9 Install piston ring (oil scraper ring) (6a) by hand.    
10 Install piston ring (taper-faced hook scraper ring) (6b) with piston ring pliers. IMPORTANT Observe installation position of piston ring (taper-faced hook scraper ring) (6). The marking N must point upwards.
SPECIAL TOOL Pliers
Fig 1
11 Install piston ring (plain compression ring) (6c) with piston ring pliers. IMPORTANT Observe installation position of piston ring (plain compression ring) (6c). The marking N must point upwards.
SPECIAL TOOL Pliers
Fig 1
12 Offset piston ring end gaps of piston rings (6a, 6b, 6c) by in each case 120° at circumference of piston (5).    
13 Install pistons (5).   AR03.10-P-7021MFC 
CHECK VALUES FOR PISTON RINGS

Number Designation Engine 260
BE03.10-P-1001-05L Piston ring vertical clearance Groove 1 mm 0, 03...0, 07
Groove 2 mm 0, 02...0, 06
Groove 3 mm 0, 01...0, 18
CHECK VALUES FOR PISTON RINGS

Number Designation Engine 260
BE03.10-P-1002-05L Piston ring end gap Groove 1 mm 0, 2...0, 3
Groove 2 mm 0, 3...0, 5
Groove 3 mm 0, 2...0, 7
Fig 1: Identifying Pliers (000 589 51 37 00)
G13655415Courtesy of MERCEDES-BENZ USA
REPAIR MATERIALS

Number Designation Order number
BR00.45-Z-1028-04A Assembly cleaner A 000 986 56 01