worship79

Well, a little over 6 years after building my 383 she ended up in total self-destruction.

What happened
After a nice day of easy road cruising I decided to add some highway miles. Everything went okay and she drove as always. I'm an "objects in mirror are losing" kind of driver, so it was spirited driving with a bit of sprinting here and there. No endured high-speed driving though, as the highways were too crowded for that.

How it ended
Then, before heading home, I decided to take one last sprint and used the kick-down from a highway insert. Starting at a speed of about 20 miles I pushed the pedal and we hurdled onto the highway. About half a mile further along, at a speed of... 80/90 miles a sudden blow, rattles all over and a sound like I was driving through gravel. White smoke and oil all over...

First I checked if I hadn't just lost my v-belt, causing the engine to overheat. But those were still in tact and the wetness was on the driver side at that. One look down and I knew I was .... because there hung what only could be a piston ring.

How do I determine the cause?
Not quite sure I want to build another engine or just buy a crate/already built and be done with it. However in any case I want to know what went wrong here.

Given this side blow-out. What should I check next/first?





Both plugs on nr.'s 5 and 6 looked like this and for both cilinders a rocker has been forced aside. Note the sludge I found under the carb and in the intake.







Here are pics of the cilinderheads, crank, camshaft and rods.

Left cilinderhead:


Right cilinderhead:


Close-up left chamber for nr. 5 cilinder:


Close-up left chamber for nr. 6 cilinder:


Close-up nr. 5 piston rod:


Close-up nr. 6 piston rod:

HeadsU.P.

What I find interesting is the gouge in the con-rod. The angle of that connecting rod looks a little out of whack or maybe its the photo. Almost looks like that con-rod lost a bearing and cap first, then struck the side of the block.
Then things began to get worse, worser, worstest. Hard to say. Is the piston missing? Can't see.

I am no expert on throwing rods but I would say, that may not buff-out.

Sorry for your loss. Thankfully winter is coming and the best time to regroup.

stingr69

I think you threw a rod through the side of the block.

Need to tear down a bit more to see what failed first. Could be a piston, pin, or rod bottom came apart. One of those let go and the crank came around on the next rotation and smashed the rod out the side of the block. My guess money is on a hypereutectic piston disintegration first but it could be any one of the other things let go first.

New engine time for you....Have you been a good boy this year? Maybe Santa will bring you a short block?

worship79

I have found a piece of what appear to be a piston stuck in my (now flat) rear tire... Think part of it is still in the cilinder.

Whaha! I think I agree on that.

Thanks!

I do have (or: had) hyperteutic pistons. KB's that came with a kit from Jegs, similar to this one: https://www.jegs.com/i/Eagle/356/B13101E030/10002/-1

Santa has me looking at a 400 block, bigblock, LS, another stroker...

Big2Bird

The truth is you may never know, and it won't make a bit of difference.

Jamb in a crate motor and carry on. Buy the one that has those goodies you wanted anyhow.

OMF

MY guess from 1500 miles away......Rod bolt failure. they are the most stressed fastener inside your engine.

And given that side blow out.....the only thing to check is which one of your friends has an engine hoist

Vette5311

I have become a NON believer in hyperutectic pistons, for what it is worth!

sambrand

ive seen similar blow outs, usually caused by a con rod breaking and the piston end up cockeyed in the cylinder, this seldom causes a blow out all the way through the coolant passage unless the engine was under load (ie in gear) and the rotational energy was conveyed throught he wheels causing the engine to continue to rotate, good news is you don't have to replace everything but I would recommend a new crate 4 bolt main and you can keep all your oem intake exhause etc. also though now is the perfect time to install better heads and intake especially if your wanting headers or already have headers,

derekderek

it doesn't matter. It was either the crank, or it was a rod bearing. Or a rod bolt. Either way the crank the rod the engine block is all scrap metal. Don't cry over exploded milk and start shopping for another engine.

derekderek

The only question is did the heads survive? If you're missing a valve head, that could be very well what happened it gets in there get sideways makes the piston stop and bad things happen.and if all the valve heads you're still attached to the stems, are the heads worth hanging onto? Are they plain heads or are they something special?

jb78L-82

Ok..I checked your signature and you had a 4 bolt truck block with eagle 383 crankshaft and connecting rods (I am assuming not forged) as well as the dreaded Hyper pistons. Could be anything but those hyper pistons and 383 stroker cast steel crankshaft kit (?) make me suspicious.

I can tell you when I did my 355 L-82 build in 2014 and mentioned hyper pistons innocently just for feedback, my builder who did the bottom end of the motor, said he would not do the bottom end of my motor with hyper pistons. He said "they are junk" and will implode at the slightest detonation. I used JE Forged racing Pistons (pistons alone were about $700/set). I reconditioned my L-82 forged crank, reconditioned the OEM L-82 forged rods, with new ARP bolts everywhere etc. It was expensive but I was going to do as much as possible to avoid the terrible outcome you have just experienced. I was building a fairly stout 355 L-82 and was not going cheap anywhere. Not a fan of Bill Clinton but I feel your pain....

worship79

Thanks all! I know: bygones be bygones. Seven steps in the process I guess...

@ jb Correct: bottom end not forged, did use all ARP bolts throughout.

@ Derekderek: heads are Edelbrock performer (60909) with CompCams 1.52 roller tip rockers. Heads have been cc-ed en springs shimmed. Block was zero decked, and torqueplate honed.

@ Big2Bird: as it looks, I can reuse the top end and perhaps my XE274H nitrated camshaft + comp dual chain, etc. This is relatively expensive over here and there is not a large market to sell them on to (without considerable loss).

I'll be pondering my options for a while I guess.

HeadsU.P.

On the good side of a event like this is, its not likely any metal shavings went into the oil system destroying salvageable parts. So you should be good to go if you purchase a short-block.

Hang on to the block and four connecting rods. That will make a hella of coffee table with a story behind it. If you have never seen a bare block coffee table with con-rod legs, I believe I spotted them on Etsy maybe? Or try Google pictures. Radical stuff for a man-cave.

DUB

I hope you find the engine you want due to what happened to this one is a shame. Not that it matters but I would go with a LS conversion myself. I work on several and they are great on gas and also have wicked power.

I am a believer that it all started with the connecting rod....as what we called them at the drag strip a 'rodney'...because they would often times fail and sometimes it was a piston literally melting down and then cause catastrophic damage to an engine. I have seen enough oil pans that when they were pulled off that what was laying in the bottom of the pan looked like a hand grenade was set off inside it.

DUB

ddawson

[img]http://coreshotmedia.com/upload/2018...85d631c50a.jpg[/img]

Vette5311

Big2Bird

Over here? Where is here?

derekderek

As it currently looks, you have no clue what you can use and what you can't. a couple of rods that let go you have to check those combustion Chambers in the cylinder heads for any kind of impact damage with those Pistons. that piston went up and smack that head hard at head could well be no good whatsoever.the cam? No way. Too much stuff flying around within inch of that camshaft I'll bet you that camshaft is snapped in half.I'm just still possibility with a valve head let go and blue the Piston up and caused it all in the first place and then when the valve head got wedged between the piston in the top of the head it will also have destroyed that cylinder head.

Rescue Rogers

I think a piston pin came apart then the rod came loose and sawed your block in half, regardless yo had a bed component that you wont be able to identify until the motors out and the heads are off. On the bright side, as you said, you are up for an upgrade. It sounds like you like to express your joy for Horsepower so I would look at building a small block 427, which can reuse your top end and accessories , A LS3 5.3 conversion which can be expensive getting all the parts to fit, or the crate engine pre built but with all the trimmings you desire. I like to build my own stuff so I can do the quality control and if it blows then I know it was my fault. Plus if it runs good I can proudly say i built it.

Good luck, keep us updated

OldCarBum