I've got an 89 Bronco II with a 2.9L engine. It cracked a head, and so I went ahead and put two rebuilt heads on the engine. The mechanic told me he changed the lifters, turns out the guy is a compulsive liar and didn't. It started tapping right after getting it back, now it's getting worse, and worse and worse... it sounds at times like it's going to break the rocker arms off!

So, the engine is tapping like crazy now, and I'm afraid that instead of just lifters, it's going to need rocker arms, maybe even a camshaft (if that is possible).

What can I expect in the way of cost, to replace the lifters in this engine?

=ALSO=

Just recently while on a trip I noticed something odd with the oil pressure. It went to zero at idle, and as I rev'd it up, it went back up - so while I was driving it was fine, but then slowing down it would go all the way to zero. When it's cold, it has decent pressure all the time - I can drive probably 20 miles no problem, but as it warms up, it will disappear at idle speeds (like at a red light or stop sign). Any clue what is causing this? Now scare me and tell me the engine has to be lifted to get to what looks like the silliest oil pan design I have ever seen - to replace the oil pump if that is what you guys think it is?

Do you think my first problem (all the clacking) is just due to this goof not replacing the lifters?

Do you think my second problem is the oil pump?

Thanks for your help.
Mike