Engine - Single or Multiple Ticking Noises
88chrysler02 Models1988 M-N-B-D-AW Models Equipped With 3.9L & 5.2L Engines
Subject
Tappet Noise
Index
ENGINE
Date
March 7, 1988
No.
09-01-88 REVISION A
P-928
This bulletin supersedes Technical Service Bulletin 09-01-88 which should be removed from your files. This bulletin revises the labor operation time allowances for air conditioning equipped vehicles and updates the 3.9L intake manifold gasket package part number.
SYMPTOM/CONDITION
Some vehicles equipped with "LA" family engines (3.9L or 5.2L built prior to October 29, 1987), may exhibit tappet related noise. This condition can be identified as a single or multiple ticking noise originating in one or both cylinder banks. The noise is due to air trapped in the tappet. The causes usually involve one or more of the following:
^ Insufficient oil fill of tappet
^ 1988 roller tappet socket/solid push rod leak condition
^ High clearance/high dry lash
^ Seized/sticky/defective tappet
^ Insufficient oil supply to tappet
DIAGNOSIS
The vehicle should be started cold and operated in park or neutral at idle. Isolate the noise for bank and approximate cylinder location. The noise can also occur intermittently at higher rpms, and can be checked by increasing the engine speed to approximately 2500 rpms and holding it there. The noise should cycle in and out, possibly changing locations. Remove the cylinder head covers on the noisy bank(s) one at a time. Check the rocker shaft fastener torques. If loose, retorque and re-evaluate the engine noise. If noise is still present, proceed with the repair procedure.
PARTS REQUIRED
12 *Tappet & Push Rod Package - 3.9L PN 4494467
1 Intake Manifold Gasket Package - 3.9L PN 4397732
16 *Tappet & Push Rod Package - 5.2L PN 4494467
1 Intake Manifold Gasket Package - 5.2L PN 4494462
* Small "c" on axle of roller
REPAIR PROCEDURE
This procedure involves replacing the hydraulic tappets and push rods.
1. Remove the cylinder head covers and intake manifold.
2. Remove the rocker shaft assemblies.
3. Remove the push rods and tappets from the engine.
FIGURE 1:
4. Fill the new tappets, PN 4387682, in the following manner:
a. Insert the end of a wire or rod through the oil hole in the push rod socket, and push down gently until the push rod socket moves down inside the tappet body approximately 1/4" (Figure 1).
b. Holding a finger over the oil inlet hole, fill the exposed cavity in the roller tappet body with 10W30 engine oil.
c. Slightly extract the wire from the tappet body, allowing the push rod socket to rebound to the retaining clip. The oil placed in the tappet body now enters the roller tappet through the hole in the push rod socket.
d. Repeat Steps a. through c. until the push rod socket becomes "solid". A socket is determined to be "solid" when a load can be applied with a push rod and the socket does not move.
5. Install the new filled tappets in the engine.
6. Install intake manifold, using procedure outlined in appropriate service manual.
7. Install new push rods, PN 4483721. Install rocker shaft assemblies and torque fasteners to 200 inch pounds.
WARNING: THE ROCKER ARM SHAFT SHOULD BE TORQUED DOWN SLOWLY, STARTING WITH THE CENTER-MOST BOLTS. ALLOW 20 MINUTES TAPPET BLEED-DOWN TIME AFTER INSTALLATION OF THE ROCKER SHAFTS BEFORE ENGINE OPERATION.
8. Install cylinder head covers.
Engine should be started to verify elimination of tappet noise. If some tappet noise is still present, operate engine for 30 minutes at varying rpms (900 - 2000) or until noise is gone.
POLICY: Reimbursable within the provisions of the warranty
TIME ALLOWANCE:
Labor Operation No. 09-85-02-92 - 3.9L B Models . . . . . . . . . . . . . 3.1 Hrs.
D-N Models . . . . . . . . . . 3.0 Hrs.
09-85-02-91 - 5.2L B Models . . . . . . . . . . 3.6 Hrs.
A-D-X-W-M Models . . . . . . . 3.5 Hrs.
09-85-02-60 - A/C Equipped B Models . . . . . . . 0.8 Hrs.
A-D-X-W-N-M Models . . . . . . 0.4 Hrs.
FAILURE CODE: 68 - Noisy