Strange Metallic Whirring Noise

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Never did hear the noise.

I had a starter drive come apart in such a manner that the fork no longer pulled the gear back allowing the drive gear to move into the ring gear every time the car accelerated, making intermitant noises similar to those described.
 
Well I tried swapping the balancer, and while it was worn, it did not cure the noise. I also checked for excessive timing chain slack, and there really is none. I did take the stethoscope and listened on every header tube and sure enough, the front tube on right side, or cylinder #2, the noise was most present on that one. Still came and went though. Definately isn't a bearing of any kind since it is intermittent and no oil pressure changes. Additionally, it doesn't have that sound or that of a piston pinot, being that it is more of a metallic rattle. So with that said, I will be pulling the right side valve cover tomorrow: I will be investigating the rockers for that cylinder and the pushrods. I think I'm getting close....
 
Look at the lifters too. Sometimes, it is exploratory surgery to get to these issue. We had to pull the covers to positively ID a loose lifter.
 
nm9stheham said:
Look at the lifters too. Sometimes, it is exploratory surgery to get to these issue. We had to pull the covers to positively ID a loose lifter.
Click to expand...

Ding ding ding! This is what I did last night. All of the valve train was tight, so on whim, I put some Marvel Mystery Oil down the pushrod bores of cylinder number 2 and onto the top of thone lifters and buttoned things up. Started it up and no noise. Drove it 10 miles, varied engine speeds, and shut it off a few times, and never once heard the noise. And it was running smoothly. I'll keep an eye on it, but maybe there was a small piece of dirt or something inside the lifter keeping it from pumping up properly? Who knows.
 
OK that is good. Now keep in mind that the engine stops in different positions with different valves open, and sometimes will put higher open valve pressure on a lifter with issues, and other times not. This may cause a leaky lifter to leak down badly at some stops, and not much at all at other stops. And a some faulty lifters take overnight or a few days to leak down.

So keep an ear on it for a while. If it comes and goes, then cleaning may not do the trick. We seem to have one of those that comes and goes, and eventually, it'll have to come out.
 
Update: been a couple weeks with a couple hundred more miles of driving under the belt. Noise still gone
 
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