340 with metal in oil pan

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jason's duster

jason's duster

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OK so I’m going to make a long story short my engine was making a very slight knock so I pulled it it’s a 340 out of my 69 Dart and I found these in oil pan. Any ideas where they came from?

BF64BB7A-66C9-4CEA-B64A-3F9FB9A91591.jpeg
 
Ouch! That does look like a valve seat. Compression test will tell you if it’s one currently missing from the head or left in there from another KABOOM! Whats the history of the motor?
 
I don’t know the history on the motor I just bought the car a little over a year ago and haven’t had time to really drive it much it started making a slight knock so I stop driving it pulled the engine and found the metal. After I left this post I pulled the heads and somebody put one of my pistons in 180° the wrong way and the valves have been tapping the piston I am believing this would explain my debris ending up in the oil pan?
 
That's not a valve seat, that's a valve LOCK.

And yes, that would make sense if the piston made contact with a valve and shattered the lock. So you likely have a bent valve and a valve spring that is free of its retainer. Not good.

EDIT-

Based on that picture you'd better make it two bent valves.
 
72bluNblu said:
That's not a valve seat, that's a valve LOCK.

And yes, that would make sense if the piston made contact with a valve and shattered the lock. So you likely have a bent valve and a valve spring that is free of its retainer. Not good.

EDIT-

Based on that picture you'd better make it two bent valves.
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It could be depending in the diameter of the debris... Hard to tell in the picture he posted...

jason's duster said:
Here is the piston

View attachment 1715461131
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The piston still looks useable, but like bluNblu posted I would have the valves checked for straightness, guides checked to make sure they are round and not oval, then the head can be repaired... New seats for sure....
 
jason's duster said:
Any reason to remove rotating assembly or just repair heads?
Click to expand...

If it turns over by hand with no hang-ups (remove all spark plugs so you're not fighting compression), then the rotating assy should be ok... Fix the head(s) and go...
 
It all needs to be taken down to it's smallest components and everything needs to be "Santa Claused", as in check everything twice. They put a piston in backwards, why would you think they may haven't messed anything else up in the bottom end? That's a new one on me, I suspect liquor (or worse) may have been involved... Wonder how many of the rod bearings are oiling the cam and how many are throwing oil to the outside of the block. Untelling what surprises await.
 
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Or the piston is correct and the block is upside down, rotate the picture 180°... :poke:
 
krazykuda said:
It could be depending in the diameter of the debris... Hard to tell in the picture he posted...
Click to expand...

I agree pictures can be misleading, but with that kind of curvature the diameter is way too small for a seat.

If it's got a "small knock" like the OP described the whole thing has to be disassembled.
 
Personally I’d go over everything. The rods on the big end have a large and small chamfer. If the piston is backwards there’s a good chance the chamfer is incorrect. You “may” find crank damage.
 
Ok I’m tearing down to the smallest components. Thank you for all your help. I will update in near future. And yes liquor was prob a factor. Can’t fix stupid.
 
72bluNblu said:
I agree pictures can be misleading, but with that kind of curvature the diameter is way too small for a seat.

If it's got a "small knock" like the OP described the whole thing has to be disassembled.
Click to expand...

I think that you're correct on the valve keeper/retainer as that will fall in the crank case and into the oil pan when it fails...

If it were a valve seat, it would have fallen into the cylinder and would have beat up the piston top... I've seen that too many times... There would be many small dents in the top of the piston if the debris fell into the cylinder...
 
jason's duster said:
Ok I’m tearing down to the smallest components. Thank you for all your help. I will update in near future. And yes liquor was prob a factor. Can’t fix stupid.
Click to expand...

When you tear it down, make sure that they have the rods correctly oriented to the pistons.... The squirt hole should be on the same side as the valve relief "eyebrows" and point to the inside of the block, and the anchor slots should be on the outside of the block...

Here's a thread on how that all goes together...

How to Rebuild a Small Block Part 7: Install Pistons in Block

I'm still working on the rest of them to complete the series....
 
They are your tops of the valve spring retainer keepers. The valve are falling out . Been there.
 
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Tear it down. That's gotta be a valve lock, don't see how a seat could end up in your oil pan anyways. Plan on going through the whole thing as long as it's out; none of it looks promising- but at least you didn't ventilate the block. You might be able to save the rotating assembly, just inspect EVERYTHING and replace what's necessary. Then reassemble it RIGHT. You've seen the results of shortcuts.
 
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