Outer Exhaust Manifold Studs Breaking on 1991-1999 Jeep 2.5L engines - Engine Builder Magazine

Outer Exhaust Manifold Studs Breaking on 1991-1999 Jeep 2.5L engines

Inspect either manifold stud for breakage, if breakage is noted, perform the repair procedure outlined below.

Models Affected:

1996 – 1999 (AN) Dakota

1991 – 1992 (MJ) Comanche

1997 – 1999 (TJ) Wrangler

1991 – 1999 (XJ) Cherokee

1991 – 1995 (YJ) Wrangler

NOTE: This information applies to Jeep vehicles equipped with a 2.5L engine.

REPAIR PROCEDURE:

This bulletin involves replacing both outer mounting studs, clamps, and
nuts with new parts and tightening the outer studs to a reduced torque
of 180 in.lbs. (20 Nm).

1)    Remove the intake/exhaust manifold per service manual procedures to gain access to the broken stud(s).

2)    Remove the outer studs from the cylinder head. Use a stud removal tool if possible or drill the broken stud from the head.

3)    Install two new outer studs p/n 06036193AA into the cylinder block. Torque the studs to 126 in.lbs. (14 Nm).

4)    Clean any carbon deposits or debris from the exhaust manifold.

5)    Reinstall the exhaust manifold.   **Use only the new parts listed above to attach the outer ends (Figure 1).

6)    Torque the bolts in the order and specification as listed in Figure 1.

Some or all of this information was provided by the Automotive
Parts Remanufacturers Association (APRA). For more information on
technical bulletins available through APRA call 703-968-2772 or visit www.AutoBulletins.com.
Figure 1

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