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As soom as the intake valve dropped from the one cylinder, there was an open passage for chunks to get sucked back up into the intake portion of the head and over into the other cylinder.

 

Espescially when you consider that as the damaged side is on it's "compression stroke" the adjacent piston is travelling *down* on it's intake stroke.

 

Cyl. 1 = pushing to eject, while Cyl. 3 = sucking in. Not to hard to understand.

 

Now if that had been an exhaust valve that dropped it would be different. Or if it had been a set of dual port heads, where the runners are seperated, it would be odd.

 

But there isn't any big mystery here other than what was the first thing to go. My bet is valve.

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Here's an update.

 

I take back what I said. The object that subymech pointed out is not part of the piston. It is not alluminum. I had noticed the piece (we will call it FOD since we are calling it FOD!) and it looked like aluminum, I figured it to have been a piece of piston that exited #1 via vacant intake valve and into #3 via working intake valve. This piece is definately steel, it sticks to a magnet.

 

There are only 2 possibilities. This piece came through the intake, or it came from the crankcase via vacant #1 intake valve. I need to crack the case and see where this came from. I have a broken down engine in my shed I will look for where this piece came from, barring that I will need to take the case apart, If I can't rotate the crank enough to pull the pins, can I just Pull the case apart with the pistons still attached to the crankshaft?

 

I will post pics of FOD removed from the piston. The plot thickens!

 

A couple things bother me, one is Abog posted that pieces of crap were found under his carb after such catastrophe. I have already installed the intake with carb on the replacement engine. Never looked for debris. Been running the car. Also, if FOD came down the intake, what is to say there's not more where that came from? I'm running the same intake. We'll see.

 

For those that didn't read the seized engine thread, This was a newly installed 63K engine with a new out of box weber on top. Engine sat for 10 plus years, and I do think there was pressure built up in the crankcase. see the seized ea71 thread for details.

 

Any mistakes were most likely mine, ie, tools etc. unless the guy I got the engine from hucked a nickel in the head for good luck......

 

But I honestly don't think I left anything to chug down the intake.

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Some of that valve/piston found its way (got sucked) into the other cylindar through the head. Looks to me like a classic sucked valve. Sorry. that sucks especially now that aluminuim values are down.

It's most likely a piece of the valve, which you can see from the pics has been modifyed from its designed shape. What ever it is I bet it came from within (that motor ate itself).

Edited by ihscout54
I sounded like a d*ck for no reason
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Did you take the bellhousing off the back of the block and look at the gears? Were you able to split the case and look at the and cam journals?

 

Something caused the valve to hit the piston. This doesnt just happen.

 

While I will agree that the piece embedded into the piston is alarming there will be something more glaringly obvious if the block is split I think.

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The FOD is definately piston ring. I have nearly recunstructed the entire ring!

 

Shawn, the bellhousing is off, But I can't get the case apart. I don't think it's neccessarily true that the piston and valve met while both intact. Couldn't be as simple and unpredictible as a flaw in the metal of the piston. Engine sat for 10 years plus and was than run at 80 mph for over 200 miles straight, piston cracks, flies and hits valve. I will open the case in the next few days. Can you do that w/out pulling the wrist pins? also I can't get the oil pump off.outer shell came off but left the base plate and such on the block.

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I was gonna say, your object embedded in the pistons looks to be part of a compression ring.

 

I'm pretty sure we have established something came apart.. but I havent seen anyone mention reversion (negative pressure wave caused by the other cylinders drawing air out of the intake) yet...

I had an EJ motor come apart, and it looked nearly identical in every way to this.

I should suspect, looking at your pictures, that the head of the valve snapped off ( for reasons none of us may ever figure out ) and destroyed that piston, shattering it and the rings (which proceeded into other cyl... see below) and thereby caused the resulting damage.

The damage done to the other cylinders I would suspect is due to pressure reversion which will have the tendancy to take all the little broken bits and pieces, such as that piece of piston ring, and suck them back into the intake manifold, then evenly distribute them across the rest of the otherwise functional cylinders, thus resulting in the classic "buckshot" pattern seen on the remaining pistons...and total failure of these remaining functional cylinders.

 

You must remove the wrist pins before the engine will completely separate, but you should be able to crack the block with the pins in... perhaps a larger hammer/wedge? Keeping in mind they are glued together quite tightly...

 

Sucks that it happed, man... Hope the next one goes better for you.

88RxTuner

Edited by 88RxTuner
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I was gonna say, your object embedded in the pistons looks to be part of a compression ring.

 

I'm pretty sure we have established something came apart.. but I havent seen anyone mention reversion (negative pressure wave caused by the other cylinders drawing air out of the intake) yet...

I had an EJ motor come apart, and it looked nearly identical in every way to this.

I should suspect, looking at your pictures, that the head of the valve snapped off ( for reasons none of us may ever figure out ) and destroyed that piston, shattering it and the rings (which proceeded into other cyl... see below) and thereby caused the resulting damage.

The damage done to the other cylinders I would suspect is due to pressure reversion which will have the tendancy to take all the little broken bits and pieces, such as that piece of piston ring, and suck them back into the intake manifold, then evenly distribute them across the rest of the otherwise functional cylinders, thus resulting in the classic "buckshot" pattern seen on the remaining pistons...and total failure of these remaining functional cylinders.

 

You must remove the wrist pins before the engine will completely separate, but you should be able to crack the block with the pins in... perhaps a larger hammer/wedge? Keeping in mind they are glued together quite tightly...

 

Sucks that it happed, man... Hope the next one goes better for you.

88RxTuner

 

 

Okay, now I'm freakin terrified. Heres the deal, regardless of why the initial catastrophy happened, what was said in this post makes a lot of sense. There was a lot of aluminum debris in cylinders 2 & 4 as well. I had initially thought that this mashed stuff had squeeked past the piston rings. Looking at it again, some pieces seem too big for this to be possible. Therefore they went all the way across the intake manifold. Surely there was debris left in the intake manifold, And I never thought to look in there and clean it out, as I hadn't seen what this engine looked like inside. That intake is now bolted to the new engine and the car has been run for an hour and driven a few miles. There is a good chance I have screwed up the new engine. What would you do at this point. I hardly want to pull this motor and take the heads off. I suppose I could take the manifold off, clean it out and pull the plugs and blow the cylinders out. What a freakin mess this whole thing is. The worst is that the new engine is from an FE and I really don't want to destroy it. Not exactly common. So what would you guys do from here?

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STOP!!!!!!! RIGHT WHERE YOU ARE!!!!!!!!!!!!!

 

Run for an hour, like idling and warming up, and put-putting down the road?

 

have you gone WOT on this new engine?

 

Step one when you grenade an engine... DO NOT move parts to your new engine without THOROUGHLY steam cleaning all nooks, crannies, passageways, etc. and replacing all vacuum hoses, check valves, tee's, and any other place where debris COULD, no matter what the chances, end up....

 

I hope we dont have to do this again, for your sake...

 

I would remove the intake, remove the throttle body and all fittings, accessories, vacuum tees, etc, Remove anything that was on the old engine, THOROUGHLY pressure wash / steam clean the intake runners and ALL accessories...

 

I would also pull all the spark plugs and put a flashlight down the tube, rotate the engine by hand and see with your own eyes whether any damage has been done or not. If not, maybe stuff one of those extend-o-magnets down there and see if you get any steel out of your cyl's. Better now after an Hour than let the rest of that crap float into your cyl's...let this be the basis for whether or not you pull the heads off again.

88RxTuner

Edited by 88RxTuner
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