The 1998 Jeep Cherokee was available with a 6-cylinder 4.0 litre engine. As with all engines, rebuilding the 4.0 litre requires careful attention to detail. One of the most important and commonly overlooked details is the engine's torque specifications. Tightening a bolt too much can damage the component it is designed to secure, and may even break the bolt off inside of the engine block. Failure to the tighten the bolts enough can cause them to come loose and cause severe engine damage. Use a torque wrench and follow the specifications to tighten the bolts to their proper settings.
Unlike most engines, which feature an intake manifold and an exhaust manifold as separate components, the 4.0 litre engine uses a combination manifold that is removed and installed as a single component. The torque specification varies depending on the location of the manifold's bolt. Tighten the bolt at each end of the manifold to 17ft-lb. of torque. Tighten the remaining bolts to 23ft-lb. of torque.
The head bolts must be tightened in a particular sequence. Tighten each head bolt to 22ft-lb. of torque, then tighten all bolts to 45ft-lb. of torque. Tighten all of the bolts a third time to their final torque setting of 110ft-lb.
Tighten the crankshaft's bearing caps to 80ft-lb. of torque. Tighten the rod bearing caps to 100 in-lb. of torque.
Tighten the harmonic balancer bolt to 80ft-lb. of torque.
Tighten the crankshaft pulley's retaining bolts to 20ft-lb. of torque.
Rocker Arm Shafts
Tighten each of the rocker arm shaft's bolts to 19ft-lb. of torque.
- 20 of the funniest online reviews ever
- 14 Biggest lies people tell in online dating sites
- Hilarious things Google thinks you're trying to search for