check engine AUDI A4 1996 B5 / 1.G AWM Engine Valve Gear Service Workshop Manual

15-74

Hydraulic valve lifters, checking


Special tools and equipment

Feeler gauge
Wood or plastic wedge

Note:
Hydraulic valve lifters cannot be adjusted or
repaired.
Irregular valve noise during starting is normal.

Test sequence

- Start engine and let run until coolant
temperature has reached approx. 80 C.

- Increase engine speed to about 2500 rpm for 2
minutes (perform road test if necessary).

Note:
If the irregular valve noises stop but recur
repeatedly during short journeys, a new oil
retention valve must be fitted. Oil retention valve
location: In oil filter bracket -Item 6 -, Page
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15-88

Valve seats, reworking


Note:
If a good seating pattern cannot be obtained by
grinding the valve seats (lapping), they must be
refaced (reworked):

Special tools and equipment

Depth gauge
Valve seat machining tool

Note:
When repairing engines with leaking valves, it is
not sufficient to reface the valve seats and
replace the valves. The valve guides must also
be checked for wear. This is particularly
important on high mileage engines Page 15
-
86
.

Only rework the valve seats as far as is
necessary to ensure a good seating pattern.
Before starting to rework the valve seats,
calculate the maximum permissible reworking
dimension.
Pa
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gear, servicin
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11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.GE06.15.2