[461bird]

First post-hello to everybody.....Has anyone else had a eagle cast crank break, 3 in. main, 4.25 stroke. Was in a street car, 5 speed, 2.78 gears - approx. 2k miles on the motor when it let loose. Never a problem with oil pressure or over heating. Hope pic. went thru-thanks to all that respond.

[Txbobcat]

WOW

[74Grandville]

what rpm did you run the engine too.

[461bird]

5800.....broke at approx. 5000 rpm in first gear accelerating from a stop sign out on a country road-no warning at all,no shudder or anything else.

[J.C.you]

any dowel pins in the pan, block split?

[400 plus]

Originally Posted by Txbobcat

WOW

My words EXACTLY

[grivera]

What's the casting number on the block?

[2manyponchos]

What brand of balancer? My cousin had a similar failure at about 1000ft on 1/4mile pass. No warning, just boom. His crank split just behind the 1-2 rod throw. Pretty text book torsional failure. The damper was also wasted. I believe the damper was a CAT. I have compared his failed crank to an Eagle that I have and there is a difference in the 2 pieces that I would like to understand. His crank was drilled into the 1-2 rod pin from both sides with a large diameter drill to remove material. My crank (unbroken) is only drilled from one side and not all the way through?

[old66tiger]

One of the main reasons why I spent the extra $200 on a forged unit. The aftermarket cast units are not like the nodular units of years past. Ask Cliff Ruggles about his experiences with stress fractures in the cast units.

[GTOLou]

Post/pic of the day...WOW..

[screamingchief]

Originally Posted by grivera

What's the casting number on the block?

That ^^^^ was my first thought too.

Could easily have been the blocks fault if it were a 557 block.

The fact that this crank came apart right in the area that those blocks are known to fail (second & third main journals) kinda supports that theory at the moment.

Plus I can see pieces of a busted main web right at the top LH corner of the pic...

Originally Posted by 2manyponchos

What brand of balancer?

And this ^^^^ was my second thought.

It's all too easy to blame a crank for a failure like that,but honestly it could be almost anything that leads to these sorta failures.

We're always at the mercy of the owner to fill us in on all the details before we can even begin to take a WAG at what might be to blame.

FWIW

Bret P.

[rexs73gto]

Was the crank & the complete assy. balanced before you put it together. If it wasn't that could also point to a problem because the newer cast cranks I don't believe are true balanced when there sold to anyone. Trosional vibration with mismatched parts will do just what your seeing in those pics.

[TheCirque]

The headline on the newspaper sitting on the table in the upper right of the pic is funny.

"U.S. Steel Takes Serbia Hit"

LOL

[lust4speed]

How did the balancer end up over an inch out on the crank? If the crank bolt backed out, that would explain things.

[461bird]

Was a 988 block and yes it broke at the #1 & #2 mains. Engine was professionally built by a company that participates on these boards. I bought it as a complete crate motor minus distributer & carb for $11,000.00 in 08. I wanted a forged crank but they recommended a cast stating its good to 600hp-they dynoed this motor at 534hp, 561lb-ft. Damper was a professional products rated to 6500rpm according to paperwork recieved with motor. Car was used for local cruise nites and drives around town.

[grivera]

Was it converted to 4-bolt caps? Splayed? Studs or bolts? Have you been in contact with the builder for their opinion/assessment/resolution?

[Bruce Meyer]

Must have had too many chop sticks in the mix when that crank was cast.
There have been a lot of Eagle cast crank failures over the years. Do a search, your not the only one. They are junk and should never be used for anything. Well maybe a mailbox stand.

[72LuxuryLeMansLa.]

Originally Posted by grivera

Was it converted to 4-bolt caps? Splayed? Studs or bolts? Have you been in contact with the builder for their opinion/assessment/resolution?

Exactly what I'm wondering! What is the builder saying/doing? I would think that an inspection by them would verify if engine was oil starved or abused and they should be willing to make things right to preserve their reputation over something like a defective crank. I'm not saying the crank is defective or that there is any particular fault by the customer or builder. This may just be bad luck but the builder needs to see all of the parts to figure this out. By the way, welcome to PY Forums.

Karl

[Mr_GTO]

$11K holy F. Wow.

[461bird]

Block was 2 bolt-ARP studs. Minimal contact with builder as they are hard to get ahold of, haven't returned e-mails. I do know that they still use these cranks and they said they've never seen one end up like mine.