I'll guarantee you he did NOT hydraulic that cylinder. That appears to be a woodruff key or crank snout key. Was there anyone around while you had the intake off? It happened to me so it is a possibility. Was there anything like a crank key laying around like on a workbench or ?? I wouldn't rush out to buy anything until you get a good look down in that cylinder, most likely with the shrapnel that was in there combined with the broken piston the walls are undoubtedly scored. Remember,,
.030 is not very much material so it may need to go out .060 or need to be sleeved to clean it up. Since that piece of whatever bounced around in there so much there is even a strong possibility of a bent rod. I don't mean to be giving bad news but with the type damage you have you have to be sure of everything. Good luck

 

Yep..
several possibilities. I'll start with the closest first.
PM me when you;re ready and know what you need for sure. heads, blocks, misc rods w/ pistons etc.

Sorry to see this. Lets focus n getting it fixed.

 

Holy sh*t!

These guys where right.

Hard to tell what that thing is. The piece off the head seems to fit the entire area that broke off at the water jacket making the other piece seem foreign. Looking at the witness marks on the piston and head it looks like it was bouncing around in the beefy quench area at first then got wedged over near the thin coolant passage where it was able to break. Looks like evidence that a foreign object was dropped inside the engine while you had the intake manifold off that nobody noticed. A coin from a shirt pocket possibly? Because you heard a clunk on startup after the intake gasket swap and the car was fine (besides the intake leak according to you) before the work, the most likely explanation was that a foreign object was introduced during the intake gasket replacement. I mean unless you didn't drain the coolant before lifting the intake off the block I can't see how the cylinders would have been flooded with coolant before cranking either.

I once dropped a small metal object down a cylinder by accident. I had to pull the head off to retrieve it all at my expense. It was a hard learned lesson I never forgot. I didn't actually start the car and cause damage since I knew right away when something went down the engine. I tried everything to retreive it though the spark plug hole and nothing worked. One of the stupidest things I ever did. Ever since I always lay clean paper towels or stuff them inside open intake ports when doing this type of work to prevent anything from falling into the engine. This is the type of stuff I cringe could happen if I don't cover the open ports with clean shop towels and accidentally drop a nut or something without noticing and then start the car. I could not imagine having to explain that to one of my customers.

 

Junk that engine.

Get on ebay and find another engine near your home.

Or build a stroker sbc from 401 ci to 500ci with a tall deck and raised cam tunnel aftermarket "LITTLE M" or BRODIX Block.

Don't spend 1 dime on what you have in the photos for an engine that grenaded badly.

BR

 

https://picasaweb.google.com/1046378...eat=directlink

I put some more pictures of what was in the cylinder. Like I said it appear to be somesort of soft metal. The item orginally was round and had the colaped into this shape.

 

If it's magnetic, I'd bet it was a washer.....

Either way, Lee's right.. Time to focus on repairs..

 

FWIW, looking at this picture...



I would say it's a nut. You can make out what appear to be ridge lines, what appears to be the flat sides, and you can see metal folded over at the top, which would be the flange or intergral washer at the bottom of a typical nut...



I recall on my L98 car a lot of items being located on studs and then secured with a nut.

Doesn't matter at this point. Time to yank that engine.

 

96gs#007, thanks, that exactly what it was. Can you tell what size?

 

If I had to guess, I'd say 9/16" if standard or 14mm if metric Those seem to be the favorite sizes of GM engineers

Kidding aside, there's no doubt the cylinder is fubar'ed. Probably some pretty deep scarring in the walls. My recommendation...

- Determine when you need the car back on the road
- Determine how you will use it...continue as a nice cruiser or ?
- Determine your budget. If you've never built an engine before, you will be amazed at how quickly it can add up
- Determine what you can do vs what needs to be sourced to a shop

Without the above items defined, the range of possibilities will run from dropping a good used engine in there that may need nothing more than a little exterior clean-up to look nice to a full-blown stroker. The associated budget will run from ~$2,000 complete (if you do the R&R yourself) to "the sky is the limit".

 

I've always went against the grain so I am sticking by my guess of the offending piece being a woodruff key. Some of those had some flats on the side that goes into the groove. Most woodruff's are stamped out of flat stock and you can see the shear mark on them, that is what the one side of this piece looks like.
BUT, like 96GS said, it don't matter one bit what it was, it killed your engine. All the advice that he gave on planning your next move is good advice. Let us know where you are going from here.

 

What are the odds of something like that getting in there though?

anyone else around when you took it apart?

 

Put it in a vise and opened it up. Measured the thickness and about how big the threaded hole would have been, 10mm shoulder nut.

 

I see you are nearby in Atascadero. A forum member here in Santa Maria has a 391 for sale. It's a roller block out of an '89.

http://santamaria.craigslist.org/pts/2293860436.html

 

Thanks for the info but I really just want to keep it stock as much as possible. It only has 42k miles on her and she a daily driver. I have to see if the cylinder need machining. If you know anyone selling one piston and one head though.

 

looks like a piece of the piston for that cylinder that broke off and impacted the valves.
Doesn't look like a woodruff key to me,and if it was a nut that big you would see the oil pan through the piston.pull the engine and let a good profesional machinist look at it and have it fixed right.

 

 

Like the ones that hold the plastic injector wire covers in place??

 

Midnight, could just be

 

The connecting rod on attached to the piston that bashed the steel nut or woodruff key around at speed likely bent a connecting rod.

Good chance the same crankshaft throw the connecting rod is attached to is bent also.

The cylinder wall might have a crack too.

Magnaflux crack detection time and careful inspection of the crank on machinist "V" blocks and a dial indicator is required if you want to try and save that engine.

If the crankshaft is bent & / or cracked..............

It is just a L98.

How much $$ do you want to spend fixing it?

Take the money and build a stroker engine.

383 's are affordable to build these days.

Brian

 

Well,
if anywhere near Ventura/Oxnard....go to Fains machine shop for the motor repair. Might even make you a piston... and he'll balance the finished assembly.
Good guys. Real machine motor shop.

My motor is running strong11 yrs later...

20th st auto in Phx will have some donor blocks, as will J&D there is Bellflower.Good Luck bud !