[Chevelle Bob]

I'm helping out a friend with his 69 SS.
Engine has rocker noise and engine runs poorly
Engine lost a set of ported stock heads a couple years ago , different owner then,so very little info not sure what the failure was.
When I started helping , rockers ticking like they were loose and comp roller tips had burnt ball and sockets some worse than others. Oil just runs over rockers .Replaced rockers with Harland Sharp rollers and adjusted valves. Also changed oil
Engine ran good for about 200 miles, then same rocker ticking came back worse when engine is hot. We have checked spring pressure , coil bind , rocker arm geometry and checked oil pressure with a mechanical gauge (56 psi hot) taken at the lower left of engine .
Wondering if maybe cam bearing failure or cam bearing spun could cause this issue or maybe just bad lifters.
Engine is a used 427 short block that from what I can gather had a lot of 1/4 mile passes on it , cam is a Crane hydraulic flat tappet PowerMax .534/.553 lift, Heads are new Merlin II's, Harland Sharp roller rockers.
Any idea's or help would be great, this one has me stumped .
Thanks Bob

 

[Tom Mobley]

check the lift on the valves, see that they're all the same within a few thou.

I wonder what "lost" a set of ported heads means?

 

[Mike]

What year's the block ?
Post the 'block casting date'.

 

[Mastif]

I had a terrible valve train noise, and it also was worse when hot. Turned out to be a bad set of lifters for me.

 

[FRYNTYR]

If it was like that from the begining and the timing chain had been r&r"d I'd say the timing chain was off a few teeth. Excessive valve train noise with the poor running is one of the symptoms of the timing chain off. Of course could be many othere reasons as well.

 

[Chevelle Bob]

Mike the build date is L18-72

Thanks all for your help I will check out everything you all have suggested thank you very much !!!

 

[F1 Speed]

I'm not an engine expert but i agree with the posts above. It looks like the next logical thing to check would be the lifters, cam and timing set, especially if you suspect a lot of 1/4 mile passes in the past. Might want to go ahead and throw a new cam & lifters in along with a new timing set just for peace of mind if your confident everything else is OK.

 

[Mike]

Mike the build date is L18-72

Thanks all for your help I will check out everything you all have suggested thank you very much !!!

Wanted to verify that it wasn't an early block that needed the grooved cam and bearing.

 

[Chevelle Bob]

Thanks Mike , I thought that might be where you were going with that question. We're thinking at this point the best direction would be to pull the motor and at the very least inspect and freshen up the bottom end. Also check out the heads and make sure no damage has been done to them.

 

[OLDED]

noisy fuel pumps and the push rod can make you crazy sometimes too with this kind of sound - FWIW.

 

[BLT4FN]

just finished taking a 454 apart that I was told had a bad ticking noise.
Along with a bunch of other problems we found a lifter that was broken.
One of the two little retaining pins was broken and the valve part came out when we took the lifter out.