okay, so I'm busy looking for good pictures of my vette for the C3 show. I'm scouring the road down by the river for excellent sites, and I believe I got some great shots once I got about 15-20 minutes out of town. however, on the way back, I'm going about 60, and I hear a loud thud. now, my engine was clicking prior...similar to a lifter knocking, but I was told that it was from a bearplug or something similar sounding, don't recall *blushes*. anyhow, something's plugged and oil isn't getting everywhere it should in the engine, and they said it couldn't be fixed unless I rebuilt the engine or bought a new one. so now, after that loud thud...it's clicking like mad. every time I push on the gas, there's a series of loud, rapid-fire clicks until I let up on the pedal...and when I got home, popped the hood, and really listened, it seems like it's that same clicking from before, only louder, and now tied into the accelerator somehow, where it wasn't before. any ideas?

Sounds like you have a collapsed lifter or broken rocker arm. Pull your valve covers and check them.

or bent or broken pushrod..

and as redwing suggested.. pull the covers ..

I wish I could hear it. It may be upper end and valves, but from you description, I'm worried about a rod or main bearing. Get someone who knows to listen. This could be a real big problem. Don't drive it until some one skilled lends an ear.

back in the day, when I first heard it, the mechanic I took it to listened and said it was a lifter. they put a brand new cam in, did some work, said the noise would go away in about 500 miles. after 700 I took it in, they looked at the engine again, said it was because something was blocked from getting oil, and wouldn't be fixable...I'd have to have the engine rebuilt or buy a new one. they said it wouldn't hurt at all to drive. back then it sounded like it was cycling...click click click click then it would fade away, couple of seconds it'd come back and get loud again, then fade away again, when I had the car idling. now it gets really loud and rapid when I push in the pedal, I take my foot off, the noise goes away. I could prolly make a sound file of it to email to some people...I just dunno what to do. I had planned on putting that Banks twin turbo in there, but I can't afford that engine at least until April...unless Banks Power has some kind of monthly payment plan or something. dunno what to do until I get a new engine.

Did they replace all of the lifters? It really sounds like a bad lifter from your description. Check the oil pressure with a external gauge. You may find the pressure is down, in which case you could use a high volume oil pump. The high volume pump is not a cure, but could buy you a long long time without a rebuild.
If the pressure is okay, either you will need some new lifters, or you may get by with lifter adjustments.

CorvetteRacer1977 said: after 700 I took it in, they looked at the engine again, said it was because something was blocked from getting oil, and wouldn't be fixable...I'd have to have the engine rebuilt or buy a new one. they said it wouldn't hurt at all to drive. back then it

Id take it to a real mechanic.

place I took it to was Northwest Tire...their mechanics said (this is more or less exact) that the boreholes aren't letting oil through everythere it needs to be...either their blocked or worn out or something...so oil is getting to one part of this lifter, but not the other part. this was the original clicking. I have done nothing to it since the clicking became tied in with the accelerator.

"Blocked or worn out or something" What a load.

Yes the lifter bores can wear out and cause a drop in oil pressure. But that's typical in certain Ford engines. I have never seen it in a Chevrolet. Doesn't mean it could not happen. Blocked? only if the engine was dirty. If the oil was long overdue and maintance was not done, there could be a build up in the engine. But if that's the case an engine flush would help quite a bit. Not a rebuild.

Again, check the pressure with a gauge, not the one in the car. See what the oil pressure actually is in the engine. If it's good, run an engine flush chemical, then change the oil. If not, you may need a high volume pump to make up for wear.

But before going to far into it, try adjusting the lifters. You may find they are out of adjustment, or perhaps one or more failed and collasped. You can find this by adjusting them.

To adjust the lifters, remove the valve covers and start the engine. You may want to install the anti splash clips before you start it, to prevent a oily mess. Loosen each rocker one at a time until it clicks, and continues to click. Slowly tighten the rocker until the click stops. Specs for a new lifter says turn it one more full turn. This centers the lifter plunger in the center of it's travel. Worn lifters usually won't allow a full turn. Shoot for half a turn. You might need to settle for 1/4.
As you tighten them, the car may miss. Wait a minute for it to smooth out. If it does not, back off until it does smooth out, and stop there.

If you get to Zero lash (no noise) and it will not adjust anymore without starting to hurt performance and idle, the lifter is collasped. It's best to replace it, but setting it like a manual lifter will get you by for quite some time.

when the "mechanical geniuses" you took it to replaced the cam did they replace the lifters ???

most sane people would... but Ive seen way too many people reuse lifters, pushrods, springs, (note you dont have to replace spings... you can shim them.. but its bad style) etc. when you really shouldnt do this after replacing a cam.

my advice is at least follow ken's instructions... but ill go further and say unless you are 110% SURE the lifters were replaced...

buy a new set of lifters and pushrods and then adjust the lifters dynamically as ken detailed above.

in fact.. step by step, this is what you do..
1 remove valve covers
2 inspect rocker arm play.. check pushrods for bending..
3 remove distributor
4 remove spark plugs
5 insert oil pump primer (auto zone loan a tool)
6 connect break over bar to crank bolt
7 have someone slowly turn engine while you have a drill connected to oil pump priming tool.
8 make sure oil comes out of every pushrod.
9 remove carb
10 remove intake
11 inspect lifters... (pay close attention to any that failed #8, check these lifters for lateral play..
12 replace lifters, pushrods
13 reassemble top half in reverse order
14 dynamic valve adjustment

and when you do... make sure you get a GOOD brand name.. not some lifters/pushrods made by that prolific taiwanese company "soshiti"