Massive Stage II engine carnage. What do you think caused it? Painful pics inside. :)

[Alky V6]

What does it matter? It's just about all junk now. No data logs of prior runs. The rod failed. It could have been bent for many passes before this. It may not have been bent at all. You're not going to know for sure.

To people that have gone through the process of learning alky fuel, the lesson looks very familiar. Heed the warning or at least have a deep pocket.

 

[nucnova]

Ethanol is another alcohol. Not as good in a high performance application as methanol, but it's attraction is price. E85 has pump gas mixed in with it making detonation a possibility if mixtures aren't right. I'm not even going to get into the varying percentages of pump gas that you have to keep on top of with the stuff. Detonation being preferred over preignition if you're unfortunate to have either. Alcohols will typically skip the detonation mode and go straight to preignition. Preignition is not good on parts. If alcohol goes into preignition, the damage can be very quick. My second engine that I blew due to a mis-match of a/f mixture strength, static CR, boost, and the wrong spark plug happened to bend a mighty Carrillo right as the car left the line. The front end was rising, then bang! No pinging. No warning. Just a big bang, then clattering as I rolled the car to a stop. The tell tale sign was a melted ground electrode from one of the rear cylinders. The conditions got the ground electrode hot enough to preignite the mixture. The rod came out looking exactly like James'. Bearings and crank journal were fine. In fact, I'm running the same crank in the present build.
Every blown engine has a lesson to teach. Ignore the lesson and you risk having the lesson repeated to you. I have been one of the luckier alky burners. It only took two blown engines for me to learn respect for the fuel. Some will go through a storage unit of blocks before they get it figured out.

I guess that I should just count my blessings that someone with such limited engine tuning and building knowledge like myself still has all of his rods in his engine.

 

[Alky V6]

I guess that I should just count my blessings that someone with such limited engine tuning and building knowledge like myself still has all of his rods in his engine.

Yep. Avoiding the lessons is important. Alcohol lessons are not pretty.

 

[Mike E]

I would have to say that the wrist pin was too tight. Looking at the pin bore of the piston you can see black death on one side. Setting pin clearance too tight on a power adder engine is a VERY common problem with many engine builders. The wrist pin on my Stage 2 number 1 cylinder was so tight that it rotated the bushing in the rod and if I would have made a pass down the track my engine would have looked just like yours. Luck was on my side and when I tore the engine apart to fix the many other problems I found the tight pin. If the big or small end of a rod sticks for even a second the crank will tear it to shreads. A rod is no match for the rotating mass of a crank. I have pushed "cheap import" H-beam rods (which I wont name) to 1300+ hp and never bent or broken one but I always run the clearances loose. Just my 2 cents.

I've never run across this, so teach me. I'm far from an expert. On a floating pin setup. wouldn't the pin have to lock up in the small end of the rod and have issues in the piston to cause problems. I can see the markings on one side of the pin bore, but the other side is so beat up and scored I can't hardly tell what's going on there. He has some pics of the pin in the photobucket link and other than the carnage from bashing around the motor, the pin looks good.

 

[Turbo-Archie]

If the timing chain had let go first, the motor would immediately lose all power (no valves opening, no air and fuel to burn) and it would be very unlikely to break a rod with no cylinders producing power.

Wouldn't valves still be open and cause this?

One thing I noticed is that several teeth are missing from the cam gear. Not sure how that relates but it happened before the gear broke..


..

 

[Alky V6]

I've never run across this, so teach me. I'm far from an expert. On a floating pin setup. wouldn't the pin have to lock up in the small end of the rod and have issues in the piston to cause problems. I can see the markings on one side of the pin bore, but the other side is so beat up and scored I can't hardly tell what's going on there. He has some pics of the pin in the photobucket link and other than the carnage from bashing around the motor, the pin looks good.

I too was up in the air about the pin thing. With all the bashing of the lower part of the piston going on, that's a tough call. I've always run typical high performance clearances with the wrist pins with no problems. I think .0009 - .0011" was it, if I remember right.

 

[Alky V6]

Wouldn't valves still be open and cause this?

One thing I noticed is that several teeth are missing from the cam gear. Not sure how that relates but it happened before the gear broke..


..

I think if the cam drive broke first, only a few cylinders would end up with valve contact. Maybe someone else can confirm that one way or the other.

 

[Mike E]

Wouldn't valves still be open and cause this?

One thing I noticed is that several teeth are missing from the cam gear. Not sure how that relates but it happened before the gear broke..


..

Yes, if a valve is open air and fuel could still be drawn in. But if the valve never closes there is no compression. Without compression, the air and fuel charge would have very little affect and most of it would go back out that still open valve.

 

[nucnova]

Yep. Avoiding the lessons is important. Alcohol lessons are not pretty.

And...........i'm sure that you could teach me all that I need to know.

 

[Turbo-Archie]

I guess it would have less carnage..

I don't understand the missing teeth unless a chunk of debris got caught in the chain, wiping out those teeth and then breaking the chain/gear..


..

 

[Turbo-Archie]

. Without compression, the air and fuel charge would have very little affect and most of it would go back out that still open valve.

But what happens when the piston hits the valve?
It seems like you had to have some type of valve train failure in order the break the cam??
I don't think you would break the cam if the chain went first though.
The cam wanted to stop moving but the crank and chain kept going causing the cam, chain, and gear to snap.
What caused the cam to stop moving?

So, in order to snap the cam, I don't think it could be a chain/gear failure..

..

 

[Alky V6]

And...........i'm sure that you could teach me all that I need to know.

If you want to know ways to blow up an alcohol engine, then yes, I could probably teach you a thing or two.

 

[Alky V6]

But what happens when the piston hits the valve?
It seems like you had to have some type of valve train failure in order the break the cam??
I don't think you would break the cam if the chain went first though.
The cam wanted to stop moving but the crank and chain kept going causing the cam, chain, and gear to snap.
What caused the cam to stop moving?

So, in order to snap the cam, I don't think it could be a chain/gear failure..

..

With a rod failure, it's very common for the cam to break. What's left of the big end of the rod will slap the camshaft until it breaks apart. The slapping will also hurt some lifters. Maybe even jam a damaged lifter up into the lifter bore, hurting the bore. Could also explain the bent pushrod. My first engine blow up, the camshaft broke into 3 sections. One of the sections exited the block never to be found along with some rod sections. That engine used a timing chain. I don't remember what the condition of the cam drive was. The chain may have been broken, but I don't recall the gears being shattered.

 

[Mike E]

But what happens when the piston hits the valve?

It bends the valve. The piston cannot close the valve, because it does not travel all the way up into the combustion chamber.

It seems like you had to have some type of valve train failure in order the break the cam??
I don't think you would break the cam if the chain went first though.
The cam wanted to stop moving but the crank and chain kept going causing the cam, chain, and gear to snap.
What caused the cam to stop moving?

So, in order to snap the cam, I don't think it could be a chain/gear failure..

..

It's a slow day at work. I explain things with drawings all the time at work, so I figured it would be a good way to explain this.

I think the broken rod broke the cam.

 

[Alky V6]

An interesting thing about my second engine blow up. The heads came away with no contact to the head surface or the valves from the pistons. Lucked out on that one. That cam stayed in one piece too, even though you could see where the rod was slapping the heck out of it. Did damage some lifters.

 

[Alky V6]

You have to understand that there is very little clearance between the rod ends and the camshaft with normal rotation. An even worse situation with a stroker setup. If the orientation of the rod end gets out of whack just a little, there will be rod to camshaft contact, and the shock loads of that happening are going to ring throughout the engine.

 

[Turbo-Archie]

It bends the valve. The piston cannot close the valve, because it does not travel all the way up into the combustion chamber.



It's a slow day at work. I explain things with drawings all the time at work, so I figured it would be a good way to explain this.

I think the broken rod broke the cam.

Works for me, I'm visual..

Ok, so the rod broke the cam, binding it causing the cam gear to shatter..


..

 

[turbofabricator]

Looks to me the tune up was off causing the rings to butt in the bore and the rod/pin pulled outta the piston and then carnage began. Q16 and these tuning issues are easier as Donnie is alluding to. I've seen an intake valve from one side of an engine end up over into another side of the engine and beat the crap outta everything in site. Burn a plug on one cylinder and it'll kill other cylinders, too. Dealing with that right now. Thanks for sharing the carnage. I hate/love to see it. I have rods and pistons out of a 2,240 cid Rolls Griffon that windowed the block. Can't call up Dart and order one of those. We welded 'em back together, and ran them in heat races. (never in the final, though.) Anyone else think the rings butted and pulled the pin out of the piston?

 

[nucnova]

Looks to me the tune up was off causing the rings to butt in the bore and the rod/pin pulled outta the piston and then carnage began. Q16 and these tuning issues are easier as Donnie is alluding to. I've seen an intake valve from one side of an engine end up over into another side of the engine and beat the crap outta everything in site. Burn a plug on one cylinder and it'll kill other cylinders, too. Dealing with that right now. Thanks for sharing the carnage. I hate/love to see it. I have rods and pistons out of a 2,240 cid Rolls Griffon that windowed the block. Can't call up Dart and order one of those. We welded 'em back together, and ran them in heat races. (never in the final, though.) Anyone else think the rings butted and pulled the pin out of the piston?

Another possible answer in my opinion. Something stopped moving which caused that piston to be ripped apart. Something was too tight.

 

[turbofabricator]

Look closely at the top ring land to see if it's distorted. Preignition will do this. Right Donnie. Preignition is a KILLER!!! We should call our US Marines "Pre-Ignition Men" They'll kill you dead with out warning.:biggrin: