Knock and smoke

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moper said:
That was also my thought Mad... I fixed a 416 done by a local shop that has two pistons in backwards. It seemed fine during the break in, but hit valve and piston when driven hard.
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Yes, I have seen it before. The 340 that was in my 70 Dart had all the pistons installed upside down with all the valve notches facing the bottom of the cylinders. With a Mopar 484 Purple cam in it I missed a shift to 2nd without a rev limiter in it. " I just got the car" The valves ended up hitting the pistons at about 7200RPM, it dropped a valve and took out a cylinder/piston/rods/Crank/Block and everything else in its path......, I will never run a car, especially a 4spd without a rev limiter again. This was about 4 years ago. Learned big time on that one.:angry5:
 
USCG CHARGER said:
I will take the heads off tomorrow... now I just need to decide what I'm going to do about a short block! Stroker or not? Who is going to build it?
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How close to Georgia are you? If you aren't real far, I'll be glad to assemble it for you if you bring it to me.
 
StrokerScamp said:
How close to Georgia are you? If you aren't real far, I'll be glad to assemble it for you if you bring it to me.
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I a good 8 hrs from ATL.... I need to decide which route I need to go with this build after I take the heads off... I know Ryan or Brian can build me a monster but at what cost? If I let a friend do it (such as ur self) I might be putting myself in the same predicament as b4..
 
I think a local shop, with all the right equipment, and that makes you feel respected and confident, is the one you want.
 
Mad Dart said:
I can't believe that the skirt on the piston is broke when it was never really ran.

Are you sure the correct pistons were installed in that engine? Seems like the skirt may have been smacking the crank on the down stroke to do that kind of damage.
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It had steam b4 carnage. He shut it down overnight and started it again and then it went south. Could have had a cylinder full of water and broke the piston pin boss when it came up on compression. Water dont compress and either head gaskets blowing,rods bending or pistons breaking.
 
"No break in needed on a used cam and lifters if they are put back in order,"


Not true. The term "break-in" on a used cam isn't a correct term to use either. It is important for the lifters to be installed on the cam lobes that they were run on. The reason that you want to do a "break-in" on a used cam, or any cam for that matter, is because on initial start-up, you don't have oil pressure for a few seconds. What you do have is the cam lobe surfaces and the lifter bottom surfaces lubricated only by the Moly-disulfide (MO S2 for you chemists) lubricant that was, or hopefully, was put on those surfaces. That doesn't last long while the engine is running. For the new cams, the zinc in the break-in oil comes into play as the cushion on these surfaces once oil pressure is obtained and the engine is run for a short while.

Just my 2 cents.

Ken
Edison, NJ
 
Bummer!

This is why normally when I find similar problems, I shut the engine down and don't run it until I run through the paces with diagnosing and have a good idea of whats going on. That way IF there is a problem, I can possibly fix it before causing more damages and costing more $$$

Which is why you cant go off of what every guy says when they say "it just hasnt broken in yet,run it" .....well its definitely "broke" in now lol.

Its strange to say the least when it comes to chunks of the pistons laying up top. And like others said, I would expect to see some damage to a spark plug or some carnage to the valves or something with all that going on inside the cylinder.

BUT you live and learn. Now all you can do is move on and make the next one better.
 
daredevil said:
It had steam b4 carnage. He shut it down overnight and started it again and then it went south. Could have had a cylinder full of water and broke the piston pin boss when it came up on compression. Water dont compress and either head gaskets blowing,rods bending or pistons breaking.
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Well I we all don't know about that one. There could have been both. I don't see how the bottom of the piston skirt could break from water in a cylinder. Usually a Rod will bend or break but not the bottom of the piston..... We all are guessing here since none of us were there. It could be anything at this point.
 
well I pulled the head off.. found a piston that was side ways in the block with part of the cylinder wall missing.. not sure what happen... maybe rod bolt didn't get tighten? I I don't know what would cause it.. the piston is stuck in the cyl so I couldn't do anymore research. Here are a few videos of what I found.. Also my heads looked good.. I see where the piston might have kissed the valve though.. not sure if it damaged it or not... the valve is not seated all the way down now.. very small gap.

2011-11-28165005.jpg

2011-11-28164734.jpg
 
Certainly a bent valve. Thanks not too bad to repair. The block and piston is certainly another story. It looks like #4 piston got hammered or is that just water beads?
 
physixx said:
Certainly a bent valve. Thanks not too bad to repair. The block and piston is certainly another story. It looks like #4 piston got hammered or is that just water beads?
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All the piston are good on the face of them..
 
So all that happened and you did not hear anything?? It should have made a horrific noise. When I blew up my 340 taking out a cylinder it sounded like a big jar of Marbles and then a knarly KNOCK...

You sure there is not a Piece of Piston or Cylinder Material stuck under that valve?? Looks like that valve never hit anything to me from the pictures.
 
It kinda looks like that piston was hitting the valve. Did you check for piston to valve clearance when you assembled the engine? Maybe the 508 cam was too big for the notches in the pistons.

Hate it.

Another theory is that the valve was hitting the piston from the get-go and was getting bent so the thing would not return fully to the seat. The lifter started to pump up and the cam kept trying to give the valve full lift but starting from a point of already having some "lift" due to the valve not being all the way down in the seat. Eventually the lifter pumped up enough to cause the thing to hit hard enough to fail the piston. There are clearly witness marks on both the valve and piston from contact.

If the cyl hydrauliced it would not have caused the valve to get bent.

My stroker has a cyl sleeve in one of the holes. Can a cyl be sleeved even after a piston knocks a hole in it?

I didn't like the paint on the valve train either. Somebody has been doing some serious corner cutting. Cost a motor.

Still hate it.
 
It looks to me like it just hydrauliced. I would say that's not a huge possibility, but that's what it loks like to me. I guess at this point, dead is dead and "how" isnt a big deal to know.
 
moper said:
It looks to me like it just hydrauliced. I would say that's not a huge possibility, but that's what it loks like to me. I guess at this point, dead is dead and "how" isnt a big deal to know.
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exactly
 
It,s never good news when your expecting a good running engine and something like this happens.I hope this doesn,t deter you from your dream of cruising in that cool Dart.Take a step back and draw out a plan for the next build.Right now with the economy the way it is,there,s plenty of deals to be had with performance parts,complete engines.I hope you can get things figured out and move forward with a stroker build.My stroker took a dump on me also:eek:ops:,but hey,thats racing and will build again.Good luck.
 
Sucks to hear man...I just went through the whole thread and watched all the vids.

it looks like to me....so IMO...

The Piston contacted the valve, broke the skirt then catastrophically self destructed.

Did you measure the Piston to Valve clearance with playdoh...or mocking clay? .509" lift cams usually do not do this....were the installed Heights on the valves set to Spec during the head refurb?...I noticed the Smog Ports are blocked off.....what castings are those?

Was the camshaft degree'd or set Straight Up?

(1) piston was replaced ?
Was it that one? The one that is stuck in the #2 Cylinder?

More and More to this engine failure is not adding up.

Ohh and these new cars (your SRT8 Charger) will NEVER stack up to be as cool, or collectible as our Oldies....the old ones may die, but rest assured the new ones will too and will never have the resale value the 64-74 Mopar cars do.


:happy1:
 
I have to disagree with the statement "dead is dead, and how doesn't matter". Sure, it won't fix this engine, but you should at least try to figure out what happened to prevent making a similar mistake on your next build. If you learn that the piston to valve clearance was no good on this build, then you know to check it next time. Or if you learn water was getting in the cylinder, the question should be "Why?" That would be the "learn" in the phrase live and learn. Just my 2 cents.
 
That can probably be repaired just fine with a sleeve and new piston and rod.
 
StrokerScamp said:
That can probably be repaired just fine with a sleeve and new piston and rod.
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Carefully magnaflux the block and check the crank, and Stroker may be right.

On the "dead is dead" comment, I simply meant the whys no longer matter if he's planning to pay a shop to take care of it.
 
StrokerScamp said:
That can probably be repaired just fine with a sleeve and new piston and rod.
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That bent valve would also have to be adressed...probably also a guide if the existing one was damaged. Something caused the valve to hit the piston and that should also be understood.
 
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