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hi i just bought this motor and i wanted to know what kind of crank is in it, if its a 4340 forged or cast crank i was told it was a 4340 any help would be great thanks ken
 

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Sorry bud, I'm no help. I was hoping I'd be able to see casting marks around the rod journals. I know it is not a 4340. It does look like a really nicely done cast crank. Look for some markings (numbers).
 

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Usually a crank that heavily shot peened is cast. I had a Scat cast steel crank that was peened heavy like that. Never saw a 4340 crank that heavy.

Scat and many others put their info on the fron of the fron counterweight. Its hard to see with the front main cap in the way sometimes. Might need to remove it.
 

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i was told it was a scat crank it is about 7 years old i looked with a flash light it has no stamping on it
 

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Usually a crank that heavily shot peened is cast. I had a Scat cast steel crank that was peened heavy like that. Never saw a 4340 crank that heavy.

Scat and many others put their info on the fron of the fron counterweight. Its hard to see with the front main cap in the way sometimes. Might need to remove it.
Yeah, if you can pull that front cap off and look for some casting marks.
 

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I have seen only one other crank like that, came from Doug herbert.... supposed to be a 4340.......

are all the rod throws gun drilled like the one in the pics...... i am fairly sure you have a herbert 4340 OFF shore crank....... no -name....... who ever they get them from

in fact it looks totally like one of there rotating assemblies....for about $1200.00

do yourself a favor and put a better crank in it.......
 
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