Checking distributor: VW (AAX, JJ)

AAX
Checking and adjusting conditions

Minimum engine oil temperature 60°C

A - Checking centrifugal advance with TDC sender

Specified => page
28-6
.

Connect ignition tester V.A.G 1367 or V.A.G 1767 in accordance with instructions.
Pull vacuum hose off.
Set engine speed to 950 ± 50 rpm.
Note the indicated angle = basic angle.
Increase engine speed slowly. The beginning of advance is shown by the higher number of degrees.
Set engine speed to next test speed.
Read off advance value on tester.
Work out centrifugal advance angle.

Indicated advance angle
- · Basic angle
= · Centrifugal advance angle

Repeat test at the other test speeds.

B - Checking centrifugal advance with stroboscope lamp

Specified => page
28-6
.

Connect ignition tester V.A.G 1367 or V.A.G 1767 in accordance with instructions.
Check ignition timing; if necessary, adjust.
Pull vacuum hose off.
Set engine speed to 950 ± 50 rpm.
"Bring notch back" to timing mark.

Note indicated angle = basic angle.

Increase speed slowly. The beginning of advance is indicates by movement of the notch.
Increase engine speed to next test speed, "bring notch back" to timing mark and read off advance value.

Work out centrifual advance angle:

Indicated advance angle
- · Basic advanceangle
= · Centrifugal advance angle

Repeat test at other test speeds.

C - Checking vacuum unit for leakage

Advance unit

Connect vacuum tester between carburettor/intake manifold and advance unit. Switch tester to throughflow.
Increase engine speed until tester shows a higher vacuum than that given for the end of the advance.

Note:

If no vacuum is indicated by tester the connection on the carburettor/intake manifold is bloked.

Switch vacuum gauge so that vacuum is maintained on the vacuum unit side.
The indicated vacuum must not drop more than 10% within 1 minute. Otherwise renew vacuum unit.

D - Checking vacuum advance angle

Desired values => page
28-6
.

Connect ignition tester V.A.G 1367 or V.A.G 1767 tester in accordance with instructions.
Connect vacuum tester between carburettor and advance vacuum unit.
Switch tester to throughflow.
Start engine.
Set engine speed to 950 ± 50 rpm.

Checking with
TDC sensor:
Note indicated advance angle = basic angle,
Stroboscope:
"Bring notch back" to timing mark and note indicated angle = basic angle.

Increase engine speed until gauge shows a higher vacuum than that given for the end of the advance.
Switch the vacuum tester so that the vacuum is maintained on the vacuum unit side.
Set engine speed to 950 ± 50 rpm.
Lower vacuum on vacuum tester to the test value - advance end or advance begin.
Note the advance angle (by "bringing notch back" when checking with stroboscope lamp).
Work out vacuum advance:

Indicated advance angle
- · Basicangle
= · Vacuum advance angle

Compare angle with desired value for advance end.