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Remove/Install Brake Booster - AR43.10-P-0350MFB

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Model 118.###2#, 177.###2#, 247.###2# 

Fig 1: Brake Booster Components Location - Model 118.###2# (Shown On Model 177 With Engine 260)
G16050159Courtesy of MERCEDES-BENZ USA

Shown on model 177 with engine 260 

G16050160Courtesy of MERCEDES-BENZ USA
DANGER Risk of fire  due to ignition of R1234yf refrigerant on hot components. Risk of poisoning  caused by inhaling overheated refrigerant vapors. Risk of injury  to skin and eyes caused by contact with escaped R1234yf refrigerant and when working on pressurized parts. Risk of explosion  due to formation of ignitable refrigerant/air mixtures Never perform welding work on or near a closed air conditioning system. No smoking or open flames. Wear safety glasses and protective gloves. Work only in well ventilated rooms. Carry out repair work on the air conditioning system circuit only after the system has been evacuated. AS83.00-Z-0007-01A
DANGER Risk of death  when working on component parts and systems with U >= 30 V alternating voltage (AC) or U >= 60 V direct voltage (DC) Do not touch damaged or defective live component parts and lines or non-insulated electrical connections and lines.
Model 118.### 2#, 177.### 2#, 247.### 2# with engine 282 with code ME08 (Hybrid drive 75-84 kW VARIANT (INCLUDING PLUGIN))
AS00.00-Z-0035-01A
DANGER Risk of accident  when commissioning the vehicle due to a lack of braking effect when the service brake is operated for the first time after repair work. Before starting the engine, actuate brake pedal several times until pressure is built up and maintained in the brake system. AS42.50-Z-0002-01A
WARNING Risk of poisoning  caused by inhaling overheated refrigerant vapors from an air conditioning system containing R134a. Risk of injury  to skin and eyes caused by contact with liquid R134a refrigerant and when working on pressurized parts Never perform welding work on or near a closed air conditioning system. No smoking or open flames. Wear safety glasses and protective gloves. Work only in well ventilated rooms. Carry out repair work on the air conditioning system circuit only after the system has been evacuated. AS83.00-Z-0006-01A
WARNING Risk of injury  . Skin or eye injuries may result when handling hot or glowing objects. Wear protective gloves, protective clothing and safety glasses, if necessary. AS00.00-Z-0002-01A
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 poisoning  from swallowing brake fluid. Risk of injury  from skin and eye contact with brake fluid Only pour brake fluid into suitable and appropriately marked containers. Wear protective clothing and eye protection when handling brake fluid. AS42.50-Z-0001-01A
Notice  Information on preventing damage to electronic components due to electrostatic discharge   AH54.00-P-0001-01A
Notice  Notes on avoiding damage through contamination and foreign objects   AH00.00-P-5000-01A
Notice  Notes on self-locking nuts and bolts   AH00.00-P-0001-01KOA
Notice  General information on vehicles with high-voltage on-board electrical system and/or lithium-ion battery and/or gaseous-fuel drive system as well as personal protective equipment Model 118.### 2#, 177.### 2#, 247.### 2# with engine 282 with code ME08 (Hybrid drive 75-84 kW VARIANT (INCLUDING PLUGIN)) AH00.00-Z-0300-01A
Notice  Brake fluid notes   AH42.50-P-0001-01A
Notice  Notes on repairs to brake system   AH42.00-P-0003-01A
Notice  Notes on externally invisible brake fluid loss   AH42.10-P-9406-02A
  Notes on safety-relevant components   AH00.00-Z-0019-01A
REMOVINGINSTALLING Remove/install     
1 Reduce vacuum in brake booster (1) by depressing brake pedal several times.    
2 Clean area around brake fluid reservoir (2) thoroughly. Assembly cleaner *BR00.45-Z-1028-04A 
3 Remove cap.    
4 Remove sieve from brake fluid reservoir (2).    
5 Extract brake fluid from brake fluid reservoir (2).    
6 Install sieve into brake fluid reservoir (2).    
7 Attach cap.    
8.1 Remove the catalytic converter. Model 118.### 2#, 177.### 2#, 247.### 2# with engine 282  
    Model 118, 177, 247 with engine 282.8 AR49.20-P-0100MFA
    Model 118, 177, 247 with engine 282.9 AR49.20-P-0100MFD
8.2 Remove exhaust gas aftertreatment unit. Model 118.### 2#, 177.### 2#, 247.### 2# with engine 608  
      AR49.20-P-1500MFE
8.3 Remove engine with transmission. Model 118.### 2#, 177.### 2#, 247.### 2# with engine 139, 260, 654  
    Model 118, 177, 247 with engine 139 with transmission 724.1 AR01.10-P-2401MFG
    Model 118, 177, 247 with engine 260 with transmission 724.1 AR01.10-P-2401MFJ
    Model 118, 177, 247 with engine 260 with transmission 724.0 AR01.10-P-2401MFC
    Model 118, 177, 247 with engine 654 with transmission 711.63 AR01.10-P-2401MFS
    Model 118, 177, 247 with engine 654 with transmission 724.1 AR01.10-P-2401MFF
9 Remove brake lines (6) from hydraulic unit (7).   AR42.40-P-0816MFA
10 Remove refrigerant lines from expansion valve.   AR83.30-P-5520MFA
11 Remove holders for power electronics. Model 118.### 2#, 177.### 2#, 247.### 2# with engine 282
with code ME08 (Hybrid drive 75-84 kW VARIANT (INCLUDING PLUGIN))
 
      AR08.00-P-0005MFH
12 Remove right engine mount. Model 118.### 2#, 177.### 2#, 247.### 2#  
    Model 118, 177, 247 with engine 282 AR22.10-P-1102MFD
    Model 118, 177, 247 with engine 608 AR22.10-P-1102MFE
13 Release and disconnect electrical connector from brake vacuum sensor (B150).    
14 Cover painted surfaces in the repair area. NOTES
Protect painted surfaces from brake fluid. Otherwise damage will be caused by escaping brake fluid.
 
15 Clean master brake cylinder (5) in area of connections of brake lines (6). NOTES
Thoroughly clean area around connecting points before opening the brake system. Otherwise minute dirt particles in the hydraulic components result in malfunctions and total failure of the brake system.
 
    IMPORTANT Only use clean, lint free rags and cleaner free of mineral oil.
Do not use any compressed air for cleaning when the brake system is open.
 
    Assembly cleaner *BR00.45-Z-1028-04A 
16 Remove brake lines (6) from master brake cylinder (5).    
  Note on calculation of tightening torque when using insertion or socket tools with various effective lengths   AH00.00-P-0015-01CW
    NOTES
Seal connections immediately.
Otherwise damage can be caused by escaping brake fluid.
 
    IMPORTANT Collect escaping brake fluid.  
    TORQUE SPECIFICATION Retaining screw, brake line to master brake cylinder *BA42.10-P-1002-04Q 
    SPECIAL TOOL Box wrench bit Fig 4
    SPECIAL TOOL Record plug Fig 2
17 Move brake lines (6) far enough into holders to free up the installation space of the brake booster (1). NOTES
Do not deform brake lines (6).
Otherwise failure can occur to the brake system.
 
18 Detach vacuum line (3) from brake booster (1). INSTALLATION IMPORTANT Ensure that seal is correctly seated.  
    SPECIAL TOOL Record plug Fig 2
19 Check seal of vacuum line (3) in brake booster (1) for damage. If damage is found,

Replace seal of vacuum line (3) in brake booster (1).
 
20 Release and disconnect electrical connector (4).    
21 Remove electric line from brake booster (1). SPECIAL TOOL Dismantling tool Fig 3
22 Remove lower trim for instrument panel on driver's side.   AR68.10-P-1501MFA
23 Remove screw (9). TORQUE SPECIFICATION Bolt, brake pedal brake booster retaining bolt *BA43.10-P-1002-01L 
24 Remove nuts (8). TORQUE SPECIFICATION Nut, brake booster to front end *BA43.10-P-1001-01L 
25 Remove brake booster (1) forward. NOTES
Do not damage boot when removing/installing brake booster (1). Otherwise the brake booster (1) will fail.
 
26 Remove master brake cylinder (5) with brake fluid reservoir (2) from brake booster (1). When replacing brake booster (1).  
      AR42.10-P-0300MFA
27 Remove brake vacuum sensor (B150) from brake booster (1). When replacing brake booster (1).  
28 Install in the reverse order.    
INSPECT Check     
29 Perform brake test on roller brake test stand.    
REFER TO MAINTENANCE Brake test   AP42.00-P-4290BA
BRAKE LINES

Number Designation Model 118 Model 177
BA42.10-P-1002-04Q Retaining screw, brake line to master brake cylinder Nm 16 16
BRAKE LINES

Number Designation Model 247
BA42.10-P-1002-04Q Retaining screw, brake line to master brake cylinder Nm 16
PNEUMATIC BRAKE BOOSTER

Number Designation Model 118 Model 177, 243, 247
BA43.10-P-1001-01L Nut, brake booster to front end M8 Nm 22 22
PNEUMATIC BRAKE BOOSTER

Number Designation Model 118 Model 177, 243, 247
BA43.10-P-1002-01L Bolt, brake pedal brake booster retaining bolt Nm 22 22
Fig 2: Identifying Record Plug (129 589 00 91 00)
G11971934Courtesy of MERCEDES-BENZ USA
Fig 3: Identifying Dismantling Tool (000 589 95 63 00)
G15042193Courtesy of MERCEDES-BENZ USA
Fig 4: Identifying Box Wrench Bit (140 589 00 03 00)
G13668668Courtesy of MERCEDES-BENZ USA
REPAIR MATERIALS

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