Chrysler Repair: 1996 Chrysler Cirrus lifter tapping, cylinder head bolts, ft lbs torque

Question
Hi Roland,

I recently purchased a 1996 CirrusLX 2.5L from someone who didn't want to spend the money to repair it after overheating on the highway
( Dodge dealership said could cost $1500 to replace head gasket ).  Car overheated due to water pump leaking, no water in the oilpan, however, there is a predominant "tapping" of what sounds ( to the untrained ear ) like the lifters...

1.) Oil light comes on when key turned on, goes out when started.

2.) Vehicle has 47,000 original miles ( reason I bought it ), with oil changes every 3000 miles ( verified with CARFAX ).

Could the water pump failure caused the lifters or something else inside the engine to be warped or damaged?  I would be grateful for any insight you might provide.  

Answer
Hi Gregory,
The tappet noise could be well due to a compromise in the oil delivery to the cylinder head as the result of either one of the gaskets being compromised or perhaps at least not being torqued to the necessary level to prevent a loss of oil pressure and thus delivery of oil to the valve train. The manual shows that oil to the lash adjusters, camshaft jounals and rockers depends upon a passageway thru the #2 camshaft cap above the cylinder head.
There is one approach that you might want to try, just on a chance. You might try retorqueing the cylinder head bolts on both banks of cylinders. Loosen them in the reverse order of normal tightening to say about 55 ft-lbs. torque level. Then retighten them as if you were installing them again to the final spec. of 80 foot pounds. I have had success with this approach when a cooling leaks occured internal to the engine that were apparently caused by too loose head bolts. I just did that trick Tuesday on a little 3 cyl Geo engine which had lost virtually all its coolant on the expressway and it seems to have worked!
So give it a try, there is nothing to loose. You might also want to verify the rocker arm shaft bolts torques. In my experiences the water loss originally occured because of head bolts loosing their required torque level, rather that a water pump leak. But at least it would be worth a try. Please let me know what happens.
Roland