Alternator - Drone/Vibration
85ford01Article No. 85-1-18
DRONE/VIBRATION (2,000-2,500 RPM) - 3.8L ENGINE
FORD 1984 T-BIRD, LTD, MUSTANG
LINCOLN-MERCURY 1984 COUGAR, MARQUIS, CAPRI
A drone/vibration in the 2,000-2,500 RPM range on 3.8L equipped vehicles may be caused by alternator bracketry and/or alternator imbalance. This article outlines the procedure for alternator replacement and revised bracketry installation.
A tachometer is essential for proper diagnosis to verify the engine speed. Diagnosis should be made while driving the vehicle and in Neutral Engine Run-Up.
1. Remove the accessory drive belt, alternator, and alternator support bracket and belt tensioner assembly.
2. Remove the idler pulley/belt tensioner from the support bracket and install the pulley assembly on the new support bracket (E5SZ-8680-A). Tighten bolts finger tight.
Figure 18:
Figure 19:
3. Install the new support bracket and pulley assembly and torque the bolts to specification (Figure 18).
4. Install the new fan (E4DZ-10A310-A) and pulley (D9AZ-10344-A) on the new alternator (E5SZ- 10346-A). Install the alternator assembly to the support bracket.
5. If the 2nd and 3rd intake manifold bolts, as indicated in Figure 19 are not studs, remove the bolts and install two studs (N803949-S2) and torque to 28-38 N-m (21-29 ft.lbs.).
6. Install the new rear mounting bracket (E5SZ- 10W151-A) to the studs and torque attaching nuts (N621939-S2) to 28-38 N-m (21-29 ft.lbs.).
7. Install the brace (E5SZ-10B315-B)to the alternator support bracket and the rear mounting bracket (Figure 18) and torque the attaching bolts (E4FZ- 7A291-A) to 20-30 N-m (15-23 ft.lbs.).
8. Inspect the drive belt for excessive wear, severe glazing, frayed cords, etc. Replace the belt if it has any of these conditions. Install the drive belt and tighten to specifications (Figure 18).
PART NUMBER PART NAME CLASS
E5SZ-8680-A Alternator Sup. Brkt. C
E4FZ-7A291-A Bolt (Pkg. 5) B
N621939-S2 Nut (Pkg. 10) R
N803949-S2 Stud (Pkg. 4) S
E5SZ-10346-A Alternator C
D9AZ-10344-A Pulley B
E5SZ-10W151-A Rear Mounting Brkt. C
E4DZ-10A310-A Fan CG
E5SZ-10B315-B Brace C
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual.
OPERATION: SP10346A84
TIME: 1.0 Hr. DLR. CODING: Basic Part No. 8680 Code: 67