Kelly's engine...serious carnage! PICS

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Does10s

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Well.....something went very bad. Not sure what yet, but we have 4 broken connecting rods. The other two are bent.
Two of the rods went through the block.
One of the wrist pins with a piece of rod attached was in the pan. It ripped the wrist pin right out of the piston. The piston is wedged in the cyl. In fact all of the pistons that are disconnected from their rods are twisted in the cyl. All broken rods show the same twisted format.
All cyl. walls are either cracked or missing part of the cyl.
The camshaft is in at least 4 pieces. The rear camshaft "freeze plug" is gone. I think the back half of the cam pushed it out. Both #6 area freeze plugs are blown out. One in the bellhousing, one on the return road.
Timing chain is OK. Oil pump was still attached by one bolt. The other was apparently hit by #1 rod and it was in the pan along with pieces of the block.
Spark plugs look great. No signs of detonation, no damage whatsoever.
Fortunately, no obvious damage to the aluminum cyl. head. No valves touched a piston. No bent pushrods.
No apparent head gasket leaking.

How it happened:
I was warming it up for Kelly by driving it around the pits. I went all the way down the return road, made a U-turn and stopped. Checked all gauges, everything normal and engine is coming up to temp. I think it was about 140 degrees. Started to roll down the return road. Shifted into 2nd and pushed the thottle down to around 3/4. I wasn't floored. It came up on boost, I noticed the boost gauge swing past 5lbs. then BOOM!
It didn't rattle at all. I would guess the BOOM occured somewhere in the 3000-4000rpm range.

We haven't fully dissassembled the motor yet. The only real "clue" thus far is #6 piston top compression ring is out of it's groove and bent into where the missing cyl wall used to be. So this ring bent when the piston was still moving up. When we pulled the head this was what we saw in #6.
686815_26.jpg


Here's a pic of #3 & #4.
686815_25.jpg


A pic of #6, #5, #4 (L to R). NOTE the rods.
686815_24.jpg


And here's the window'd block.
686815_23.jpg


If you want to see these pics in full size go to http://www.cardomain.com/ride/686815

So any idea what the hell happened?
Anybody have another 250 built short block they want to sell?
I guess we'll just have to build it stronger!
Later,
Will
 
I think you'll find it was mechanical failure by physical obstruction in the first instance; something has come loose and jammed on the way around.

A "big bang" though. :shock:
 
I've heard of that Big Bang theory before...


Seriously though thats a tough break, and its worse not knowing the culprit...soon enough though you'll be back out there having fun, and then we can continue to live vicariously through you.
 
Will, was the entire oil pump bolt in the pan, or just the head, with the shank still in the block? I was thinking maybe you didn't get one of the bolts tightened up when you replaced the pump. If one dropped out it could easily jam up the rotating assembly? Obviously it was something down below, and since you just had the pan off recently, it's a strong possibility.
 
wOops, its Blocken! :shock:


Our 200 and 250's are giant tuning forks. They don't have a fully counterweighted crank, and that's what shakes everything loose. At the raggard edge, lots of vibration tends to cause other problems. More power causes incipient detonationation. In my opinion, that has taken out a cylinder wall, and then the rods and then the cam.

My mates old EFI 250 Fairlane did the same thing.I t was thrashed quite a bit on a regular basis, they lads having a lot of fun with it over many weeks. Then it had a spectacular diasarrangement one night. A six can cope with lots of detonation for a while, then usually a rod ends up giving up, and it then takes out a cylinder wall and the rod takes out the cam and then block. Number 5 and 6 are the most common. Number one is less common.

Remember your first failure that caused the No 1 cylinder to need sleaving? It was most likely detonation related. Piston, rod, wall failure.

1. Track down a block,
2. look at the option of sleaving each cylinder.
3. Then experiment with more piston clearances. Look very closely at the type of pistons. In Australia, they found that the standard Ford pistons were crack prone, and that a better quality ACL or Duralilte or SpeedPro piston eliminates most wrist pin failure.
4. Look at better quality rods...forged ones with very carefull checking of the surface finish of the little end. They can gall and contact pistons.
5. Lastly, if you don't mind traking down a 12 counterweight Aussie crank, it will most likely eliminate piston and rod failures. You'll have to sleave the front snout to fit the larger US 250 timing gear and check the thrust bearing, but it should fit in okay. Best are 1994 to 1997 EF to EL.

Like all post 1969 Ford US blocks except the 370/429/460 , they used very advanced thinwall techniques. Even if core shift is nil, there isn't a heap of metal there.

The real delight with our sixes is that nothing is a irresolvable...there are plenty of good cores around to start over. Most six cylinder guys just grab another good block, and often with an army of blister pack bearings and parts, slap a replacement together with a bare minimum of work.
 
OUCH! So sorry to hear about that. :cry:

In the words of my brother; "There's the problem - you've got a hole in your block!"
 
Mike,
The first thing I obviously thought was that I missed something with the new oil pump. But the pump was still in place and the one bolt that was holding it was tight. The other bolt was in the pan without much damage at all. If it did fall out and jam up something the bolt would've had some sort of damage I would think. The washer was bent a little, but very little. Slightly distorted would be a better term.
It is still possible that the bolt came out.
Also all of the rods turn freely within their journal. The crank still turns for a little bit anyway. The broken rods end up jamming that up. I would guess the crank is still usable. I'm never going to us it again, but it "appears" to be fine.


I'm still leaning toward #6 cyl. wall distorted, cracked, and jammed the piston. But maybe when we tear it down we'll find something.

Kelly thinks this motor was possessed from the start. Our machinist had issues cutting the O-rings, but was finally successful, we tore up a timing chain, camshaft, an oil pump, two dizzy gears and one dizzy.

We have two more blocks laying around, one of which is already at the machine shop. So we'll be down for just a bit.
Later,
Will
 
Will, possibly massive hydrostatic lock. Several of the rods are twisted at the point of breakage, like one side of the piston-wrist pin jambed in the bores.
Feel very fortunate the head & valve train was spared.
Did a rod break one of the oil pump bolts where it goes into the block casting?? Was the bolt hole where the oil pump bolts to still in tact or was that part of the block broken out?? Bill
 
8) i think you spun a bearing or three that cause all that damage. by the way i have a 250 that i might be willing to part with. pm and we will talk.
 
Will, I have an Australian 250 short block, with a forged crank and pistons, that I might be willing to sell. Nice thing about it, you can get dual roller chains, performance balancers, high volume oil pumps, etc, right off the shelf. I might go with a 221ci instead, if I can find one.
I'll call you tonight.
 
wsa111":1e40xo8z said:
Will, possibly massive hydrostatic lock. Several of the rods are twisted at the point of breakage, like one side of the piston-wrist pin jambed in the bores.
Did a rod break one of the oil pump bolts where it goes into the block casting?? Was the bolt hole where the oil pump bolts to still in tact or was that part of the block broken out?? Bill
Click to expand...

Bill,
It's possible that we hydrolocked it, but I'm not sure. My experience with this motor is that the copper headgasket seal would let go long before a rod would bend/break. The gasket shows no signs of leakage into or out of the cyl and the head and sparkplugs had no signs of water.
But who knows?

I'm unsure on whether or not #1 rod broke the oil pump bolt out of the block or not. I'll take a better look at that. But it appears the first 7 or 8 threads are stripped. The block is broke right thru the middle of that bolt hole.
I'll look into this further to see how far the bolt goes into the block.
The other pump bolt was still tight and the pump still had a good seal with the block.
The only problem with this theory is that there are no marks on the rod bolts/nuts for cyl. #1.

rbohm,
I doubt a bearing spun. As the motor sits right now I can spin each of the broken rods around it journal. #2 & 5 still move the pistons up/down. The crank rotates just fine other than the broken parts getting jammed up.
When we dissassemble it this weekend we'll learn more.
I'll take some more pics too!
Nothing like good carnage pics! :shock:
Later,
Will
 
i'll go with the hydrolock theory.with probabley water from a hole or crack in the cylinder wall opened by a stab at the throttle, could have been an underlying problem.a thin cylinder wall combined with boost may have just fatigued and cracked with no damage to the head had to be water and the broken rods and cam looks like the pistons stopped first. hard to tell by the pic but the cylinder walls look thin from what i can see around the breaks.
 
It's hard to tell because the bare iron rusts so fast, but from the pictures it looks like some of the edges of the broken cylinder wall chunks in #6 are not uniform. Specifically, some edges look like very fresh breaks and one or two look older, like maybe cracks had formed for a while before the final blowout and water had seeped into them (not enough to really leak, but enough to rust/discolor the surfaces inside the cracks). Then one day the cylinder goes into boost, the cracks flex for the last time, and boom. There is a lot of carnage to other rods but I'm thinking most of that could be explained by the camshaft getting snapped and the other rods hitting it and wedging in their cylinders, etc. Just a guess.
 
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