Unhappy 57 Fuelie Update

[Mike E.]

Well, for those of you who were kind enough to offer input several weeks ago, here's what removal of the motor and teardown indicates.
Conecting rod broke off about an inch below the wrist pin.
Therefore it was long enough to poke holes in both sides of the pan, break two lobes off the cam at no. 5 cylinder and 2 lobes at no. 6 cylinder (both lots of 2 lobes were in the oil pan),. It was also long enough to break out significant chunks from the bottom of both no. 5 and no. 6 cylinder bores.
1 lifter went all the way through, into the pan, in 6 identifiable pieces and many chips and chunks.
As the rod flopped around and broke off chunks of the cylinder bore, it also dented in the bottom of one of the piston skirts.
(the rod ended up much shorter than when it broke--it's about an inch long and bent at 90 degrees)
Apparently, as the lobes on the crank were broken off, it disturbed the timing (fancy that--the front and the back turning at different rates because the middle was missing) and bent three connecting rods.
It took a chip out of one of the crank counterweights and beat up on another one.
There's absolutely no sign of anything hitting a valve.
So, I still have a pair of heads that are good, maybe a crank, and a number of paperweights that need to be degreased.
Mike

[Mike M.]

Re: Unhappy 57 Fuelie Update

bet ya do alright selling the paperwieghts. clean them in holy water first, bless em and turn em loose. seriously, wouldn't re-use the crank. its been thru a good deal of stress and replacements are plentiful. will trade a nice crank for a paperweight. mikie

[John G.]

Re: Unhappy 57 Fuelie Update

Sorry about your mishap, Mike. I'm sure this won't make you feel any better but I had this exact same thing happen years ago to my original engine too, though the damage was not anywhere near as extensive as what you describe. In my case a con rod broke off just enough above the crank pin to serve as a 'flying nub' - ruined both the oil pan and cracked the block good. My car wasn't a fuelie, though. I can imagine how upsetting this must be to you, especially at this point in the engine's history.
John

[Tracy C.]

Re: Unhappy 57 Fuelie Update

Mike,

I'm very sorry the autopsy revealed what it did, but I for one thank you very much for sharing the experience with us. This validated the sermon Duke and others have preached about the need to replace early stock rods.

I've purchased new rods for my 63 SHP as a result of the threads here on the board a week or two ago. I really liked the Crower pieces, but I have a shoestring budget. I bought a set of Scat rods and had them delivered to my door step for less than half the price. They have all the advantages of the Crowers but they wiegh about 8% more. While this might mean something to a serious "fast rap" drag car, I doubt if I will ever run it hard enough to notice it.

Good Luck finding your replacement parts.
tc

[John H.]

Re: Unhappy 57 Fuelie Update

Sorry about your findings. Did you run the block by a machine shop to see if it is salvageable? The way I read your post is that the piece of rod remaining on the crank was still turning and was not seized nor broken. Is this statement true? If so, I stand by my first post and say that your fuel unit was the culprit and had a couple of other rods bent besides the one that broke.
One broken rod would not cause others to bend. John.

[Mike E.]

Re: Unhappy 57 Fuelie Update

John--
I'm having trouble understanding how the fuel unit was the culprit. At highway speed there's no way it can flow enough fuel through a nozzle to cause an issue like that. Yes, the piece of rod rem aining on the crank was still turning--bearings were still fine.

[Roy B.]

Re: Unhappy 57 Fuelie Update

What happened is called metal fatigue

[John G.]

Re: Unhappy 57 Fuelie Update

I bought those SCAT rods too for use in my recent engine rebuild. Though the block isn't original I liked the 'insurance' aspect of the beefier rods. When the rotating assembly was balanced weight had to be added back onto the crankshaft because of the heavier rod weight. I ground off and polilshed the forging rib lines on each side of the rod beams to lighten them further. This helped a little bit.
John

[David Bodily]

Re: Unhappy 57 Fuelie Update

Mike,
I have what is supposed to be a 57 fuelie block in my 59 that I am redoing. because the engine is not original I have decided not use it . The 57 block was rebuilt 22 years ago but never completed. It came with the car that way. The guy I bought the car from sealed the cylinders when he puit it aside and when I uncovered one bore it was pristine. I do not know the block #s and there are no heads.

[John H.]

Re: Unhappy 57 Fuelie Update

This failure might have occured while the engine was running. The problem bagan when you shut the engine off long ago and on several occasions. There is a problem with the early FI units that allow fuel to be cyphoned from the fuel meter bowl into an open intake valve after the engine is shut down. The result is that fuel in liquid form (non compressable) floods the cylinder that has the open valve. The next time you try to start the engine, the piston comes up on the compression stroke and since the liquid fuel cannot be compressed, something has to give - in your case the rod bends slightly. After this happens, every compression stroke (and subsequest liquid fuel flooded conditions) bends it a little more until it reaches a point where it breaks. Chances are that if you have other rods that are bent, they too (individually) had the intake valve open when the engine was shut off (cyphoning fule) and started the same process bending the rods toward failure. Does that make sense? I used my own layman terms - I am sure the FI rebuilders/experts can use better scientific terms and know of this problem and how to fix it. Hope this helps - someone more knowledgable may chime in. John.

[Mike E.]

Re: Unhappy 57 Fuelie Update

John--
I've owned 11 fuel injected Corvettes, and rebuilt over 20 fuel-injected units. I've experienced hydraulic lock of a cylinder when the anti-siphon valve failed. This was nothing like that. Let me tell you--the way these rods were bent, there would have been major vibration issues and much more. This was a strong-running, no-vibration motor that would run up to 6000 rpm with no vibration whatsoever.
I appreciate your input, but I'm solidly convinced that this had absolutely nothing to do with the FI unit--it was simply a 47-year old connecting rod that failed.

[John D.]

Re: Unhappy 57 Fuelie Update

Rev. Mike, When you get your fuel engine back together I strongly suggest you install a siphon breaker kit on the old fuel injection unit. It does help prevent hydraulic lockup and bent connecting rods or worse. It's a hard sell for me until after the fact. Good luck, John