Duracast Crank?

STEVE29

Registered User
I know the likelyhood of having a duracast crank is very slim. I recently bought a motor and it didn't have a flywheel or harmonic dampener to tell if it was neutral balanced. The previous owner said it was a late 89 build which would tell me its a forged crankshaft but after I pulled the oil pan and looked at the crankshaft I'm not sure anymore. The number on the last main seems to indicate it is an 89 block (E98 ECA). The crankshaft weights do appear to have holes drilled in them for balancing (sorry forgot to take a picture of that) but the crankshaft also has numbers that appear "cast" into it. There is also some number stamped onto one of the counterweights (9E 398 with an N above the number), but searching those hasn't revealed anything. I took some pics, they are not the best. I've checked the other posts about Duracast cranks and I'm still not sure. Anybody know for sure by looking at the pictures? Need to know before I purchase a balancer and flywheel. Thanks in advance.
 

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See if you can take a better picture, something like this which is an example of a forged crank in an SC block.
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The casting parting line is another way to tell if its cast or a steel crank. I just foget which is which at the moment.
 
My understanding is the welds on the crank for forged are upwards of 1/2" wide and are rough finish. Cast crank had narrower and cleaner finish.

2 or 3 knowledgable guys walking thru the shop pointed out the forged cranks immediately.
 
Thanks everyone. I think it may be a forged crank. While I was taking more pictures I think I found a casting/parting line on one of the counterweights and near another journal on the opposite end. They are wide and don't line up. From what I read on another thread, the crank is twisted during the forging process and so the casting/parting lines won't align. What threw me off was that I wasn't expecting to see the raised numbering and lettering on the crank. Are there any other tell tale signs? I added some more pics. Let me know if what I'm seeing is right. Sorry, don't know how to add large pictures directly into the post.
 

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I've never seen a duracast crank, or anyone post a picture of one. I'm calling yours forged, as it looks just like the other picture as well as what mine looked like.
 
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