Tapping from engine

If it's your tappets (hydraulic lifters). Noise in the rocker arms

And not something mechanically broken, such as a rocker arm bolt (you'd be skipping too!)

Imma Jeep CJ 5 kinda feller, I know them well, I answer the CJ 5 & 7 forums a lot!

Your mileage may reflect a good bit of wear, on every part of the valve train!

You might also, think about pulling your valve covers and see if there is a Mechanical problem causing the worst of the ticking (loose rocker arm bolt, bends, holes worn in the rockers, bent push rods)

If maybe your Tappets (lifters) are not operating as they should, because of Goop/ carbon buildup/ anything similar. You might try this, before you break out the wrenches:

Do an oil change, substitute 1 qt. Of MARVEL MYSTERY OIL for 1 qt of motor oil. This will sort clean and free up the internals of your Tappets (will not restore metal into the push rods and rocker arms, etc. [Sorry])

Tappets READJUST the Push rod Slack to the Rocker arms every time they drop down into the oil pressure in the oil galley, that they ride in. They open and refill and Take-Up Slack. Upon raising up they Close off and function much like a hydraulic jack, oil has refilled the slack void that was there when they traveled downward.

. Unless crap prevents it from sealing off, or internals from moving. The MMO may fix that!

After you run a Full Term oil change w/MMO. Forget the Marvel Mystery oil, for now. Try a oil stabilizer (such as Hi-Tach or Lucas) Substitute it for a qt. Of oil during your oil change

If you do not understand but one thing, with additives, Do not overfill your crankcase. Ever!

After I got 25,000 miles (I let everything seat-in and wear in, before I used stabilizer, on my rebuilt engine). I started doing it on every oil change I do in my Jeep. We are still sounding good. Its been a long, long time, and many miles. The only bad thing about it is, it's about $5 more, than a normal oil change.

But to me it's a wonderful insurance policy!

Whachu Think?

The Medic