Below is one of the mentioned photos. I did not take this photo.

I just adjusted the contrast. Lost more going on here than too much water one time.

The following is a copy of part of an email I got from an experienced person in the industry who had heard from the engineer involved, "Bill". Based on it I'm wondering if perhaps the adjustment in the big end was out of length short to limit the clearance towards the rear head, and the wrist pin getting loose might have allowed the piston travel to exceed the remaining clearance and strike the head, causing the fracture and related hoopla. If so, here's some motivation to get out those trams and steel tapes and verify the main rod length, and to make sure the wedges and wrist pins are as they ought to be.

From his description of the incident I'd say it was a mechanical failure of some kind as opposed to water in the cylinder. The main rod big end strap was broken and the rod was laying on the ties when they got stopped. The wrist pin was either completely out or was out of position (can't tell from Bill's rantings). Bill says the engine was barely working and was not working water (which I'm sure he would know as on my ventures down there we experienced and discussed at length).

Further information most welcome - this one is puzzling due to differing reports.

dave

Ahh, they just need about 238 tubes of JB Weld and it'll be good as new.... ;-)

Seriously, that is one seriously broken cylinder. WOW!

That would/could make some sense, but they had been dragging it around...seems like someone would have heard any rattling and banging that would have led to this....could be everything loosened up on the way out, and a power stroke made everything want to come out the back. We had one of ours get water logged while out on lease, and it did stretch the head bolts.

I can still get mad about it.

That could be part of the issue, as I'm sure the rods have not had much done to them in years. It grows more and more curious.........

I am curious as to why the cylinder casting itself failed, as well as the back cylinder head. As another poster mentioned, doesn't water usually stretch or break the bolts and head casting because that's where the pressure gets applied? If the cause was water then the highest pressure would be when the piston is almost at the end of its stroke, and so the area of the cylinder which would see the pressure would be small. If the flange strength was compromised then that might break away too.
On this engine it appears that the whole side of the cylinder has broken away, not just the flange. And only part of the head broke away.

Actually, since water doesn't compress, the build up of pressure is immediate, and seeks to relieve itself in all directions. If the wrist pin came out, and there was water in the cylinder, it wouldn't have done anything too horrible-the steam pressure on the other end couldn't overcome the water lock-it would take additional mechanical force, ie from momentum or another engine pushing. However, I have seen old photographs of waterlock damage, and not only was it known to damage cylinder componants, but bend rods, break pins, ect.. The fact this happened almost at start up is what throws me, but whatever happened, the pushing force from the rear could have had something to do with it...in other words, had the only power being applied been from the steam engine itself, there would have been some "give".

If the piston was free, and came back with a significant BANG, the hammerblow would have fractured the block and head. It would be educational to see the fragments, and see if the head fragments remain bolted to the cylinder fragments.

I also find it curious. If this did happen during startup, and the engine was moving slow, I find this damage (including the rod issue) very strange. I have had a cylinder cock stick and remain closed (even when the other 3 were open) and the engine hydrolock. It simply rolled a revolution and the wheels stopped turning....the engine gracefully slid a foot or two to a halt-no damage.

Mark

And I've had a newly reactivated locomotive plug itself up with scale from the drypipe and completely waterlog upon its second firing. Refuse to do anything........until the cocks were removed, water and scale blown out and then no problem. Unfortunately, happened in front of a bunch of citizens, but a lot of them appeared to enjoy watching the process, especially the part where I was growling and running around with a hammer while my client followed me around asking dumb questions.

A slug of water intruding into a piston valved engine already moving under load - that's the prescription for major water related mechanical failure. Bent rods, broken crankpins, blown heads most common.

I have had another private email informing me that there were reports of some knocking evident in the locomotive from several days before the incident that was not addressed. I'm in no way able to comment on that information. If true it lends credibility to the mechanical failure theory. Knowing the engineer involved, I'm certain it wasn't an issue of crew qualification or operator error. I hope to get additional pictures and information which might help solve this mystery, if I can first solve the mystery of making them appear in this forum.

dave

Is it just me or does the piston and related areas seem completely devoid of any steam oil? It really does look like the piston overtravelled and caused the damage. Just seems strange that it's so dry.
I've looked into cylinders on engines that haven't moved for years and there's almost always steam oil lube inside.
For the record, I think it's mechanical also.

More information secondhand from those directly involved. Passed along without comment for your perusal. I am quoting the secondhand source below:

dave

More info on #2248. I spoke with Bill again and got more details. They had started out up a slight grade which leveled out after about a quarter mile. Bill was backing off the throttle when all hell broke loose. When he got stopped and on the ground to see what was up the little (wrist pin) end of the main rod was on the ties. The big end was still up. The wrist pin was found, intact, along the track a ways back. Amazing as it seems the wrist pin popped out, without getting hit by the siderods, and allowed the piston to slam back against the head. Speculation is the wrist pin nut came off at some point and the pin was being held in by the taper. When the dynamics changed (shutting off the throttle) the taper broke free and the pin popped out with amazing timing, missing the side rods.[color=#FF0000][/color]

Ah, now that explains the damage; a good hard whack from a free piston. The lack of wrist pin in the pictures is apparently not because it was removed to limp the engine home, but because it fell out.
For the record, I assumed that the water wouldn't fill up the space between the cylinder head and the piston until the piston reached a point near the end of travel. That's the point at which the pressure would skyrocket. Is that a fair assumption?
This is a really graphic reminder to go over the running gear while you're firing up, and check it over whenever you get a chance to look for loose nuts and things amiss. We rely on our senses to feel and hear and smell when there is something wrong, but it would be nice to catch these things sooner than that.

The nuts which hold running gear components - such as wrist pins - in place are usually secured in some way to prevent them from coming off.

For example, some engines have a slotted nut which is keyed through the wrist pin itself, such as Western Maryland Scenic 734 (also notice the single keys running through the nuts for the pins which hold the alligator style crosshead together on the top and bottom):



The Rio Grande accomplished the same task on the Layard style crossheads of their narrow gauge Mikados by means of a lock plate which fit over the wrist pin nut, and attached to end of the tapered pins which hold the crosshead shoe in place:



Does anyone know how the wrist pins nuts on the 2248 were secured?

Think 1896. This engine was double nutted at the wrist pin.