Windshield Area - Wind Noise
90oldsmobile12SUBJECT WIND NOISE AT DASH
(SERVICE PROCEDURE)
MODELS/YEARS 1991 BRAVADA
NUMBER: 91-T-12
CORP.REF.NO: 061007
DATE: October 1990
SECTION: 10B
Some owners of 1991 Bravada models may experience a condition described as wind noise near the windshield.
SERVICE PROCEDURE:
This condition may result from a sealer gap, or a light application of the sealer, to the seam between the windshield and the cab frame. This light application can separate and create a gap for air to pass through. To determine if either of these conditions have occurred, perform the following steps.
Figure 1:
1. Remove the cowl vent grille to expose the base of the windshield, windshield frame, and the plenum assembly (see Figure 1).
2. Visually look for any sealer skips at the base on the windshield.
3. If no gaps are found, blow compressed air at the sealer and attempt to locate air movement inside of the cab. This will help locate any non-visible gaps.
4. If either of the above conditions is found, reseal area with GMS type B silicone base sealant (P/N 1052917 or equivalent). Repeat step 3 to insure all gaps have been located.
Figure 2:
NOTE: If performing the above procedure does not appear to correct the condition, a gap at the back of the dash where the dash and cowl assembly come together with the windshield frame and plenum assembly may be the cause (see Figure 2).
When these two pieces are welded together in production, a gap may be created on the vehicle. After the welding process, this gap (as well as the rest of the joint) is sealed. If this gap is not sealed properly, a howl condition can occur.
Figure 3:
To eliminate this condition, the entire joint will have to be resealed. This can be done at the same time as procedure 1 (see Figure 3).
1. Using Bowman Distribution(R) black caulking, (P/N 19023 or equivalent) it is possible to seal the area where the dash meets the plenum assembly through the exposed cowl vent windows located on the plenum assembly.
2. Remove caulking from package and apply through the exposed cowl vent grille. Firmly push the caulking into the area where the dash and cowl assembly meet the plenum assembly. To insure proper seal, it is necessary to install the calilking the full length of the windshield. {88.9 mm (3.5 inches) from the inside of the hood opening (see Figure 3)}
3. Test with compressed air to insure all leaks liave been eliminated. Once repairs have been made, install cowl vent screen, grille, and cowl vent screws.
WARRANTY INFORMATION:
For vehicles repaired under warranty use:
Labor Operation Number: C0020
Labor Time: See current Labor Time Guide
Trouble Code: 92
NOTE: Labor Operation is coded to base vehicle coverage in the warranty system.