1999 4.0 engine tapping

[Mako 17]

Hello , new to this site. I have a question concerning my 1999 Explorer, 4.0. when I start it up it has this tapping sound, performance is unaffected, and it doesn't seem to get louder when the engine is reved. any help would be appreciated. thanks

Richard

 

[Bill MacLeod]

Hey Richard, welcome to the site and enjoy your stay.

When posting a ? about the 4.0l motor, its best to advise whether its an ohv or sohc.

Does the tapping disappear after the engine has been run a few seconds?

 

[KC's Ford]

Mako try doing a search on TSB00M12 it might give you some direction

 

[Kamaaina]

'96 XLT 4.0-ohv w/ 34K miles; mine doesn't tap when cold after start up. Mine taps when it's been warmed up a while from driving and I pull into my garage. I do notice that after a long run on the freeway the tapping disappears, sorta like the lifters are sticking and the long run frees them up but after a while they start tapping again. I change oil every 3K miles so it can't be sludge. I'm gonna try a can of engine flush next oil change and see if that helps (although the inside of my motor is spotless).

 

[marragtop]

Usually a lifter would tap when it's cold and once it warms/pumps up the tap should go away. Maybe timing chain related?

 

[Kamaaina]

I think if it were the timing chain the temperature wouldn't make a difference. I'm still gonna try the flush as it's pretty close to change-oil time for me. Please don't tell me to try "RESTORE" oil treatment; I don't believe in band-aid fixes. Oh, by the way, I use Pennzoil 10w-40 oil.