Checking check valve - AR43.10-P-0023NKB

MODEL 117, 156, 176, 242, 246 

Shown on MODEL 246 

Fig 1: Checking Check Valve - Shown On Model 246

Courtesy of MERCEDES-BENZ USA

	Risk of injury  due to fan starting unexpectedly	Do not reach into the rotation or hazard area of the fan. Wear closed and close-fitting work clothes.	AS20.40-Z-0001-01A
	Remove/install
1	Eliminate vacuum in BAS brake booster (A77)	To do this, press the brake pedal several times with the engine switched off.
2.1	Remove cylinder head cover trim	MODEL 117, 156, 176, 246 with ENGINE 607 MODEL 117, 156, 176, 246 with ENGINE 651
		MODEL 117, 156, 176, 246 with ENGINE 651 MODEL 117, 176, 246 with ENGINE 607	AR01.20-P-5014-02OLB
2.2	Remove engine cover	MODEL 117, 156, 176 with ENGINE 133 MODEL 117, 156, 176, 242, 246 with ENGINE 270
	Check
3	Connect vacuum tester (030) with test connection (031) to BAS brake booster (A7/7)	Test connection	Fig 3
		Vacuum tester	Fig 2
4	Start the engine and produce a vacuum of 0.75 to 0.8 bar by pressing and suddenly releasing the accelerator pedal	Reduce vacuum >0.8 bar by depressing the brake pedal.
5	Turn off engine	The vacuum must not reduce by more than 0.2 bar within 30 seconds. In the event of a vacuum loss >0.2 bar: ↓ Install new vacuum line with check valve (2):
			AR43.10-P-0355NKB
		Check brake booster if necessary.
			AR43.10-P-0325NKB
6	Detach vacuum tester (030) with test connection (031) from BAS brake booster (A7/7)
7	Install in the reverse order

Fig 2: Identifying Vacuum Tester (201 589 13 21 00)

Courtesy of MERCEDES-BENZ USA

Fig 3: Identifying Test Connection (168 589 08 63 00)

Courtesy of MERCEDES-BENZ USA