Turbocharger: Adjustments
Turbocharger Vacuum Diaphragm, Adjusting
Special tools, testers and auxiliary items required
• Dial gauge holder (VW 387)
• Hand vacuum pump (VAS 6213)
• Pressure control valve (VAS 6342)
• Turbocharger tester (VAG 1397A)
• Dial gauge (0-30 mm) (VAS 6341/1)
• Dial gauge extension (30 mm) (VAS 6341/3)
• Flat pickup (VAS 6341/4)
• The vacuum diaphragm must be adjusted only if the linkage was loosened.
• Adjustment is performed only with turbocharger removed.
- Disconnect the hose - arrow - from the vacuum diaphragm.
- Loosen the clip above the linkage.
- Loosen the lock nut - 2 -.
- Pre-adjust the bypass flap - 1 - above the linkage for the vacuum diaphragm - arrow - so that the bypass flap can still just be turned by hand.
- Tighten the lock nut by hand.
- Connect the (VAS 6213), (VAG 1397A) to connection II and the (VAS 6342) as shown in the illustration.
- Close the (VAS 6342) at the lever - 1 -.
- Set the slide ring - 1 - on the (VAS 6213) to position - B - for "pressure".
- Switch on the (VAG 1397A) and set the slider switch to position II.
- Secure the (VW 387) on turbocharger - arrow -.
- Secure the (VAS 6341/1) with the (VAS 6341/3) and the (VAS 6341/4) onto the (VW 387).
- Set the (VAS 6341/1) to 0 bar with 1 mm preload.
- Rotate the indicator on the (VAS 6341/1) to 0.
- Check the dial indicator for ease of movement.
- Operate the (VAS 6213) until the (VAG 1397A) displays 350 ± 5 mbar.
- The (VAS 6341/1) must display 4.1 mm to 4.3 mm, otherwise rotate the vacuum diaphragm linkage until the value is displayed.
- Tighten the lock nut by hand.
- Repeat the measurement.
• The mm specifications apply to the value read out (includes 1 mm preload).
- Release the pressure via the (VAS 6342) to 0 mbar.
- Set the (VAS 6341/1) to 0.
• The following measurements must be performed in one sequence. In the meantime, pressure must not dissipate to 0.
- Operate the (VAS 6213) until the (VAG 1397A) displays 350 ± 5 mbar.
- Read and make a note of the value on the (VAS 6341/1).
- Operate the (VAS 6213) until the (VAG 1397A) displays 650 to 700 mbar.
- Release the pressure via the (VAS 6342) to 350 ± 5 mbar.
- Read and make a note of the value on the (VAS 6341/1).
- Add value 1 and 2 and divide by 2.
• The result (mean value) must be 5 ± 0.25 mm.
If the result (mean value) is not 5 ± 0.25 mm:
- Correct the adjustment, tighten the lock nut hand tight and repeat the measurement.
If the result (mean value) is 5 ± 0.25 mm:
- Tighten the lock nut and secure it with sealing wax.
• Tightening specification: 5 Nm.
- Secure the securing plate above the vacuum diaphragm linkage.
• Make sure the securing plate is locked in place.