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I took a mechanics stethoscope and probed around the heads and timing chain to find a noise that would correspond to camshaft speed. No luck. So I kept going to the block with no luck. When I crawled under the car and probed the oil pan I heard the noise thru the stethoscope.

It was up front near cylinder 2 (or maybe 1) area. I felt the pan with my hand and did not feel any impact or interference. Maybe the front bearing is not getting lubed right? But not sure why the noise would correspond to camshaft speed vs twice as fast crank frequency. Thinking I need to drop the oil pan, but that damn driver side exhaust pipe is in the way. I'm not sure how to remove it without cutting it and then I would not be able to put it back together in my garage.

Any suggestions on next step and how to remove that exhaust pipe easily?

thx
Bob

If you have dual exhaust. I guess you don't.
Yap bitch.

The power steering cyl.needs to be dropped too.

Getting to the front pan screws are another bitch.

Fuel pump removed helps. And power steering pump removed ..

The trans oil cooler is right in the way. But you can work around it.

Better if removed. But more work..

This happened to us only once in all the Packard V8s we've built, but it is worth mentioning.

The new engine had a knocking which got worse the warmer it got. Repeated teardowns found no problems with crank or rod bearings.

Finally, one of us noted a light smear of aluminum on a crankshaft counterweight. The skirt of one of the Egge pistons had not been trimmed sufficiently and at the bottom of its stroke was ticking the counterweight.

A light touch with the die grinder and the interference was gone.

Egge pistons went through a low point of quality control several years back, but seem much better today. I only mention this as it's not an area we'd have ever thought to check with repop pistons.

One other check; confirm all the pushrods are rotating, which indicates the lifters are rotating. A noise at the front at camshaft speed could indicate a stuck lifter.

jack vines

That's maybe the 2nd or 3rd time in my time in the hobby that a engine sound turned out to be a piston skirt just grazing a crankshaft counterweight. So an obscure occurrence to be sure, but worth remembering!

Progress Report:

I pulled off the valve tappet cover to look inside. Nothing surprising in there, good oil coverage throughout. The pushrods and the lifters could be turned unless the lifter was on the lobe of the cam. By rotating the engine, I was able to twist each rod and lifter easily at some point.

Pulled the plugs and was surprised to see that the front 4 (1-4) were noticeably black whereas the aft 4 (5-8) seemed to look normal in color. The last run I did was starting and keeping at idle speed. So it was running rough and at ~400rpm but I wanted to see when that noise showed up and the initial higher rpms with the choke makes it hard to tell. There was no noise initially, and after about a minute I started to hear it clearly. Any other reason why those plugs would be so black?

Next step is to pull the oil plan. I do have the stock dual exhaust, but looks like I need to remove at least the driver's side exhaust pipe to pull that pan and that is not proving to be easy.
More to come.

thx
Bob

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Howdy,
Been busy the last couple of days and looking for some advice on next steps.

I pulled the oil pan (after cutting exhaust pipe, moving steering cyl out of the way, etc). Evidence of an oil leak at the rear end. Not sure how to tell if it is a rear seal or leaking at the oil pan. (see 1st pic)

Shocked to see that there are remnants of a paper towl in the oil pump inlet screen and in the pan. (see 2nd and 3rd pic). I did see a little piece of paper towel when I removed the mechanical fuel pump too.

Did a search all around with the pan off and didn't see anything unusual. Seemed to be a good amount of oil everywhere. A couple of the cylinders do have some vertical wear from I would guess the piston skirt? Doesn't seem like there should be noticeable wear like that , esp so soon after a rebuild. Any thoughts on how normal this could be? (see pic 4, helps to zoom in)

Any suggestions as to what I should be looking for? No signs of interference or anything that would cause this noise that I am searching for.... I had my son rotate the engine while I was under there and nothing seemed to be hitting something it shouldn't

I pulled the timing chain cover too. I went to autozone to borrow a harmonic damper puller. But after I removed the damper bolt, I just pulled on the damper and it came right off! Should I expect that since I have so little time on the engine since rebuild (probably 1-1.5hrs)??????

Timing cover had no gasket. But each timing cover mounting bolt had evidence of black RTV on it, esp at the tip. See pic 5. It looked fine to me. There was a little paper towel wedged into a couple of the valleys.
But aside from the damper coming off so easily, it all looks good.


Where to go next?????????

-Pulled the tappet cover, all rocker arms and lifters seem to turn and look good.
-Luckily found the paper towel screw up, but hard to believe that is causing this metallic noise. (i likely left that where the fuel pump attaches to timing chain cover when I was painting)
-No obvious problems looking at crank and associated piston chain except that vertical wear in a couple of cylinders.
-I did not use the stock oil baffles installed in the heads. Instead I had positive valve seals installed on intakes valves. AND I also put umbrella seals on the exhausts. Figured without the baffles and the Olds high volume oil pump mod, it wouldn't hurt to put umbrella seals on exhaust. (?)
-But since the noise I hear coincides with the timing light and doesn't start until about 1 min after cold starts, I am wondering if it could be valve related? No indication of that with mechanics stethoscope, but I don't see any indication of a problem anywhere.

Hoping smart people out there will have some suggestion as to what to look at next? I don't know what else to do.

Also what gaskets should I consider safe to reuse?
-Intake manifold
-Exhaust manifold
-Exhaust pipe to manifold
-No timing chain gasket evident
-Front seal on timing chain cover
-oil pan

Thanks for reading this.
-Bob

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Bob,

I have been following your post... My first question would be "Why is there a paper towel stuck in your oil pick up?"

I have removed the oil pans on many motors that I have rebuilt shortly after start up (Cadillac 331-500's Chev., Ford., etc.) and have never seen that amount of metal "just after start up".

If you have a paper towel stuck in your pick up, then you aren't getting sufficient oil flow. I would worry that that towel has been torn apart and drifted thru your oiling system and has clogged oil passages, etc.

Pull the rod bearing caps.

And the main caps that you can ..one at a time..

There is just no way to know where paper towel residue may or may not have gotten to, so IMO the only completely safe alternative is complete disassembly, cleaning and reassembly. Very unfortunate oversight to leave a towel inside the engine.

Yes, I do realize that I am an idiot. Before I installed mechanical fuel pump, i put a paper towel in the opening to keep crap from falling inside. I must have forgotten to pull it out.

So good thing I have this hollow knock sound that I have been chasing as it led me to pull the pan and find this mess now.

Pulled rod bearing caps 1,2,4. Pics attached. Some slight wear evident but I would think there is an initial break in with new bearings and machined journal and this would be okay. Seem like plenty of oil everywhere.

I mentioned in a previous post a little evidence of vertical scuffing in a couple of the cylinders and some wear evident on those piston skirts. Probably doesnt sound normal,??


I have seen no evidence of paper anywhere but in the pan and all over the inlet screen. Without a doubt, some of the paper towel must have 'extruded' itself through the screen in tiny bits.
Next step is to pull the heads. Those are easy enough to clean up and I am curious if there is any debris in the ports between the block and heads. I'll pull the rocker arm assemblies apart and give them (arm, rockers themselves etc) a good cleaning.

I don't know what dissolves paper towel, so I'm thinking I'll buy a new inlet screen for the Old high vol pump as I won't be able to get all the paper out of the screen. I assume I can buy those separately from the pump?

1 step forward, huge few steps back! But I'll get there.

Since I got this think mostly apart, I see that Jack has an updated cam retainer plate for sale. My understanding is that the mod allows more oil to flow past it. With the Old high volume mod (and no paper towel...) would that plate still be worthwhile? Again, there seems to be plenty of oil everywhere in this engine.

But I still can't figure out where this cam-speed noise is coming from. Maybe pulling the heads will help.

Thanks to all for reading and esp to those that are replying. Your willingness to share and your advice is crucial to me getting this back on the road. BTW, if anyone wants to hear an audio recording of this elusive sound (small file size), PM me your email address.

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