lifters tapping under a load

[charlie challenger]

I have about 500 miles on my 440 since the rebuild now, and I'm trying to find out what is making a hard rattling sound in my engine.  First I thought it was my rocker arms, and when I looked at them I noticed I had an intake and an exhaust rocker arm on backwards, so I swapped them around and tightened them down and heard the sound of the rocker arms clacking since I didn't use grease between the rods and the valves.  Now I know what rocker arm clacking sounds like.  I put some grease on those, but still the rattle is there, so now I think it's coming from the cam & lifters.  I only hear it when the engine is under a load at 2500 rpms or so. 

It just so happens I blew a head gasket recently so I'll have a chance to look in there to see if damage is being done.  I suspect lifters are not getting oil.  My question is, am I going to be able to see the holes in the cam shaft bearings when I have the valley pan off?  where should I look?

I think I blew the head gasket due to overheating since I adjusted the fuel mixture and I was probably running lean & hot. I was going 70 or so up hill on the highway.

[Chryco Psycho]

Could be just poor quality lifters that cannot handle the high spring loads , you want to get Johnson lifters

[Bullitt-]

I'm wondering why grease is needed between rods & valves...   

[charlie challenger]

I meant I put grease between the push rod and rocker arm, and between the rocker arm and the top of the valve spring.  The book said to do it like that.   

I don't remember where I got the lifters.  It was 2007 when I put them in.  I think I got the comp cam ones from 440 source, but it could have been the cheapest ones I could find on ebay also.  They are pretty noisy, but only under a load.  They're fine at startup and cruising around town.  All of them rattle like a maraca at high rpm.

I'm going to open the engine up and turn it over a few times to make sure oil is getting to the rocker arms and the cam shaft. 

If it is oiling fine maybe I'll look into Johnson lifters.  From the other site: a contact for accessing GENUNE North American made QUALITY Hylift JohnsonLifters for your Mopar call "Paul" direct at 1-800-441-1400 and enter extension #609 when prompted.

[1 Wild R/T]

Lifters don't see engine load, they open & close valves thats all.. Whether your on the gas or coasting they see the same load at the same rpm... Oil pressure may vary & they could rattle because of that.. But if your oil pressure were so low the lifters start making noises you've got bigger issues.... As was previously mentioned valve spring pressure can cause them to be noisy but typically that at idle where the oil pressure is lowest & dwell time is longest...

I think your hearing detonation, Many people hear that rattle & say it's valves.... It's not... And if thats what your hearing you need to correctly ID it & get it fixed before it destroys pistons or rings ...

[Strawdawg]

Second detonation.  Try backing off the timing as well as checking that the car is not running lean.

Also be sure the advance is not sticking at full advance and the advance curve is working properly from idle and up.

Old gas, which sounds unlikely, can also be the culprit.

[charlie challenger]

Come to think of it, I haven't timed it since I switched the tach out.  It was reading about 1000 rpm too low.  So I was timing it when it was probably about 1500 to 2000 RPM instead of 2500 to 3000.