Engine - High Frequency Noises
911 Turbo (996)1/04 1001
Binder - 1, Engine - Part 1
Date: 3-26-04
Replacing Engine - Install Additional Rear Lid Seal
Vehicle Type:
911 Turbo (996) Cabriolet
Model Year:
04 (4)
Concerns:
When engine replacement is necessary an additional seal must be installed on the engine compartment lid. This will reduce high-frequency engine noises from reaching the passenger compartment.
Information:
The 911 Turbo engine can produce high-frequency engine noises in the 2500 to 3000 rpm range. The engine noises are transferred from the engine compartment to the passenger compartment via the convertible-top compartment.
To improve noise insulation, an additional seal is installed on the engine compartment lid (Figure 1, arrow) in vehicles as of the date of introduction listed below. It will be placed on the cross member of the convertible top rest with rear lid closed.
When engine replacement becomes necessary the seal must be retrofitted on vehicles which were manufactured before the date of introduction.
Introduction:
September, 15th 2003, as of VINs:
99 54S 67 5342 USA
Parts Information:
Part Number Description
996512 711 00 Additional seal, rear lid
000 043 157 00 Cleaning solvent
N/A Tie-wrap, 1-15 cm, 1 ea.
Tools:
Side cutters
Screwdriver
3/8 ratchet with extension
Socket - a/f 10
Torque wrench 0-50 Nm (0-37 ftlb.)
Grease-free and lint-free cloth
Cleaning solvent
Plastic roller
Work Procedure:
Installing seal to engine compartment lid
1. Remove engine compartment lid; see 911 Turbo (996) Technical Manual; Group 5, Repairs, 55 90 19 - Removing and installing rear lid.
Note:
Before loosening fastening screws on lid the following points must be observed:
- Cut through tie-wrap used to hold the electrical wires to the inside of the wing.
- Remove electrical wire from the wire retainer on the pneumatic spring. To do this, press the locking tabs on the wire retainer and open the wire retainer.
Caution!
Damage to the lid due to insufficient securing and improper storage!
> A second person is required when loosening the fastening screws, to prevent the lid from slipping and to avoid damaging the lid.
> Carefully remove the lid from the guides on the hinges.
> If necessary, clean the lid for handling, and place it on a clean and level surface.
Caution!
Insufficient adhesion if the bonding surface is dirty!
> The bonding surface on the lid must be absolutely clean and free of grease.
2. Clean the bonding surface on the engine compartment lid (Figure 2 arrows) with a cleaning solvent and a grease and lint-free cloth.
3. Remove protective film on the bonding surface of the new seal (Figure 3).
Caution!
Damage to the lid and seal due to residual water!
> The length of the seal is especially designed for the spacing of the two water drain holes in the lid.
> Do not stretch the seal during assembly. otherwise the water drain holes could be covered up, pre venting water from draining.
4. Install seal on engine compartment lid (Figure 4).
4.1 Maintain a distance (X) of 0.5 mm between water drain hole and seal.
4.2 Apply upper edge of the seal base (arrow A) flush to the edge of the lid (arrow B) over the entire length of the seal and press the seal lightly.
4.3 Using a plastic roller, press the seal on the lid firmly over the entire length.
5. Install lid again.
6. Close the lid.
Note:
If the seal folds over on the end when closing the lid, open the lid again partially and put the ends of the seal into position by hand (e.g., with a large screwdriver). The seal will settle in over time and will adapt to the contour of the cross member.
Working Time:
Literature:
911 Turbo (996) Technical Manual, Group 5:
> Repairs: 55 90 19 - Removing and installing rear lid
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