catastrophic failure

[JP-s-in st. louis]

My guess is that you did not have the wires attached completely to that coil pack. This would not allow that plug to fire and then have the plug crushed by the piston. But that is just my .02...Maybe not even that much.

[David N.]

Sounds like a perfect time for an engine upgrade!

[Lil bastard]

Originally Posted by JP-s-in st. louis

My guess is that you did not have the wires attached completely to that coil pack. This would not allow that plug to fire and then have the plug crushed by the piston. But that is just my .02...Maybe not even that much.

I don't see where that could happen, though I may be wrong. How would a spark failing to fire cause the piston to travel higher in the cylinder than it normally would? And, don't we have a spark cut-out type rev limiter? When that kicks in you don't have the pistons impacting the plugs.

I would seem to me that the center eletrode and it's porcelain insulator would be much less robust than the grounds and would sustain more damage than the grounds if struck by a piston, which from the pics doesn't seem to be the case.

Looks more to me that there was something bouncing around inside the cylinder, broken ring, or even a sheared piston. That could go along with the excessive cranking - the starter puts out a lot of torque and can easily break rings and pistons in some circumstances.

There were failures of some of the cylinder lips on earlier cars, always cylinders #3 and #4 attributed to the block torqueing like this:



Wonder if something like that occurred?

Doesn't sound like hydro-lock though. It's usually the pistons which take the beating from that. And, once the plugs were pulled, all sorts of gas/oil/coolant would have come gushing out.

A borescope would give better information, but the engine would need to be torn down anyway, so it may not that helpful either.

Everything here is a guess. The only way to know for sure is to have a pro check it out.

[csu15919]

brief update, i finally got a hold of a tech who does a little business on the side. i went ahead and put the car back on my lift, and this evening he's going to swing by and take a look at it. he did mention the deal to me about the cylinder liners cracking/failing and said that it's fairly common on the 996 motors, and somewhat on the 3.2 S motors. he also mentioned the motor jumping time. he claims that some of the earlier models had issues with the chain guides having to be replaced often, and the tensioners also. basically, his intial speculations are right in line with me and everyone else, and hopefully tomorrow we'll get somewhere with this. by the way, that plug was removed from cyl. 2 (center cylinder on passenger side of motor).

alright, so considering my motor is done, and with the research i've done thus far....is it feasible to install larger cylinder liners in the 3.2 case? so far, i've found that the 3.2 and 3.4 share the same bottom end, just with a larger bore on the liners in the 3.4. i'm thinking maybe run 3.6 liners (i doubt you'd be able to safely bore the 3.2 to 3.6), with some nice head work would be somewhat cost effective in terms of upgrading. it's just a random type of thought.

[Lil bastard]

@CSU15919

As I understand it, the liners are cast-in-place and not easily swapped like many other engines.

There are companies who do this work. One of the most interesting is AutoFarm in the UK.

Don't know what kind of budget you're working with or what your ultimate goals are.

It is usually easier/cheaper to just do a total swap for a 3.2 - 3.6.

AutoFarm can bore it out up to 4.0, but they're pricey. + I don't know what arrangements or costs are available for shipment to the US.

Nevertheless, their site has a good bit of info. See them at - http://www.autofarm.co.uk/

[superglide]

Originally Posted by Lil bastard

I don't see where that could happen, though I may be wrong. How would a spark failing to fire cause the piston to travel higher in the cylinder than it normally would? And, don't we have a spark cut-out type rev limiter? When that kicks in you don't have the pistons impacting the plugs.

I would seem to me that the center eletrode and it's porcelain insulator would be much less robust than the grounds and would sustain more damage than the grounds if struck by a piston, which from the pics doesn't seem to be the case.

Looks more to me that there was something bouncing around inside the cylinder, broken ring, or even a sheared piston. That could go along with the excessive cranking - the starter puts out a lot of torque and can easily break rings and pistons in some circumstances.

There were failures of some of the cylinder lips on earlier cars, always cylinders #3 and #4 attributed to the block torqueing like this:



Wonder if something like that occurred?

Doesn't sound like hydro-lock though. It's usually the pistons which take the beating from that. And, once the plugs were pulled, all sorts of gas/oil/coolant would have come gushing out.

A borescope would give better information, but the engine would need to be torn down anyway, so it may not that helpful either.

Everything here is a guess. The only way to know for sure is to have a pro check it out.

LB,
Great forensic analysis! It had to be an event of that magnitude, to beat up those plugs in that manner. But why would someone with all of the stated problems, prior to the muffler upgrade, even spend the bucks on the new muffler; while, to use an historic analogy, "Rome is Burning"?

[csu15919]

Originally Posted by superglide

LB,
Great forensic analysis! It had to be an event of that magnitude, to beat up those plugs in that manner. But why would someone with all of the stated problems, prior to the muffler upgrade, even spend the bucks on the new muffler; while, to use an historic analogy, "Rome is Burning"?

sometimes, it's even difficult for me to determine a method to my madness. if you took at peak at my previous threads, you'd probably get a better understanding. the muffler purchase was actually to solve another issue as opposed to just an "upgrade." anyhow...for those that were interested (geez, this was a long time ago), the problem was solved. i believe i started another thread...but in short...my motor was bad. i dropped 2 valves (more than likely caused by a mis-shift), which destroyed the piston & liner in that particular cylinder. lesson learned....BE CAREFUL SHIFTING AT HIGHWAY (high rate would be a better term) SPEEDS.

[superglide]

Originally Posted by csu15919

sometimes, it's even difficult for me to determine a method to my madness. if you took at peak at my previous threads, you'd probably get a better understanding. the muffler purchase was actually to solve another issue as opposed to just an "upgrade." anyhow...for those that were interested (geez, this was a long time ago), the problem was solved. i believe i started another thread...but in short...my motor was bad. i dropped 2 valves (more than likely caused by a mis-shift), which destroyed the piston & liner in that particular cylinder. lesson learned....BE CAREFUL SHIFTING AT HIGHWAY (high rate would be a better term) SPEEDS.

CSU,
Yeah, it was an old thread; I ran across it while in the middle of a search on a related subject, and much like a puppy chasing a ball; I got distracted.

Those pics of your plugs are Hall-of Fame stuff... Too bad you didn't have the soundtrack to go along with the pics. But someone, somewhere, said "if you don't break something, you ain't trying hard enough". By this reasoning; I've tried very hard (enough) more than once during my "adventures in motoring"..... I sure hope that things have gone better for you since then, and wish you & yours a Happy '09.
Best Wishes,
Andy