Inspect condition of brake disks - AP42.10-P-4258GZ

MODEL 164, 251 

Fig 1: Inspecting Condition Of Brake Disks

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

	Remove/install
	Risk of death  caused by vehicle slipping or toppling off of the lifting platform.	Align vehicle between columns of vehicle lift and position four support plates at vehicle lift support points specified by vehicle manufacturer.
	Risk of injury  to skin and eyes caused by handling hot or glowing objects.	Wear safety gloves, protective clothing and safety glasses, if necessary.
	Notes on repairs to brake system
1	Remove wheels	Model 164
	Checking	-
2	Check brake disks (1) at front and rear axle	Inspect for scores and cracks. Hairline cracks can occur due to high stress. Ventilated, brake disks (1) with perforations and without perforations do not have to be replaced if the crack length (2) is a maximum of 25 mm. With perforated brake disks (1) measure crack length (2) inclusive hole diameter. For cracks and scores which have split open and are deeper than 0.5 mm: ↓ Replace brake disks:
		-
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3	Measure thickness of brake disks on front and rear axles using caliper gauge (010)	Observe recommended limit dimensions to ensure that the wear limit is not dropped below before the next change of brake pad, if necessary: ↓
4	Install in the reverse order

TEST VALUES FOR FRONT BRAKE DISKS

Number	Designation			Model 164 except model 164.177	Model 164.177
BE42.10-P-1001-08N	Brake disk thickness	New	mm	32	36
		Wear limit	mm	29.4	33.4
		Wear limit for maintenance service	mm	30	34

TEST VALUES FOR REAR BRAKE DISKS

Number	Designation			Model 164.175 with code 494 or 498 or 625, model 164.120/121/122/125/156/182/186/195/825 without code U29, model 164.124	Model 164.120/121/122/125/156/182/186/195/825 with code U29, model 164.175 without code 494 or 498 or 625, model 164.128/172/822/823/824/828/871/886	Model 164.177
BE42.10-P-1001-09L	Brake disk thickness	New	mm	14	22	26
		Wear limit	mm	11.4	19.4	23.4
		Wear limit for maintenance service	mm	12	20	24

TEST VALUES FOR REAR BRAKE DISKS

Number	Designation			Model 251.020/022/026/122/125/126 without code U29/225/847, Model 251.021/023/054/056/065/123/154/156/165 without code 225/847, Model 251.075 with code 498/625, Model 251.175 with code 494/625 without code 225/847	Model 251.072/124/172, Model 251.020/022/026/122/125/126 with code U29/225/847, Model 251.021/023/054/056/065/123/154/156/165 with code 225/847, Model 251.075 without code 498/625, Model 251.175 without code 494/625, with code 225/847
BE42.10-P-1001-09K	Brake disk thickness	New	mm	14	22
		Wear limit	mm	11.4	19.4
		Wear limit for maintenance service	mm	12	20

Fig 2: Identifying Vernier Caliper (140 589 00 19 00)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.