Help Identify This Crank
Thread Starter
Pro
Joined: Oct 2000
Posts: 629
Likes: 1
Please Help Identify This Crank (PICS Added)
Well I'm having trouble getting a positive ID on the crank in my Big Block, and one of my biggest concerns is it forged or cast. I'm sorta guessin FORGED but I'm not positive.
Here is the number that I have 3804815 NF from the crank. The other numbers that I've collected from the engine are as follows.
Block Casting Number 3969854
Head Casting Number 3993820
Camshaft Number 3963545
Thanks
Here is the number that I have 3804815 NF from the crank. The other numbers that I've collected from the engine are as follows.
Block Casting Number 3969854
Head Casting Number 3993820
Camshaft Number 3963545
Thanks
Last edited by Indynut; Oct 10, 2004 at 07:36 PM. Reason: Added Pictures
Pro
Joined: Mar 2002
Posts: 511
Likes: 0
From: St. Louis MO
All of this came from mortec.com .... they don't list camshaft part numbers. Good luck.
3904815....396,402...cast, nodular iron
3969854....402.......70-72...2 or 4 bolt
3993820....71......oval...OPEN...402, 113cc chamber, 255/114 ports
3993820....71-84...oval...OPEN...454 Passenger and Trucks, 113cc chamber, 255/114 ports
3904815....396,402...cast, nodular iron
3969854....402.......70-72...2 or 4 bolt
3993820....71......oval...OPEN...402, 113cc chamber, 255/114 ports
3993820....71-84...oval...OPEN...454 Passenger and Trucks, 113cc chamber, 255/114 ports
Instructor
Joined: Aug 2004
Posts: 177
Likes: 0
From: Windsor Ontario
Probably the easiest way to tell if it's forged or cast is that cast cranks ALWAYS have a "flash" line on them. There is a line on either side from end to end from when they put the sand molds together and then pour the iron into the mold. If you look closely you can see the line and also you should be able to see small bits of flashing. These were never able to be cleaned off totally and are in the areas of the rod journals - not the machined areas but the unmachined areas between the rod journals and the mains. Forged cranks do not have this to my knowledge.
Le Mans Master
Joined: Mar 2004
Posts: 7,470
Likes: 1,492
From: Little Rock AR
Originally Posted by babyiza73
Probably the easiest way to tell if it's forged or cast is that cast cranks ALWAYS have a "flash" line on them. There is a line on either side from end to end from when they put the sand molds together and then pour the iron into the mold. If you look closely you can see the line and also you should be able to see small bits of flashing. These were never able to be cleaned off totally and are in the areas of the rod journals - not the machined areas but the unmachined areas between the rod journals and the mains. Forged cranks do not have this to my knowledge.
-Mark.
Thread Starter
Pro
Joined: Oct 2000
Posts: 629
Likes: 1
Thats why I'm having so much trouble. The dang thing does ring just like a bell. But that line looks like what everyone is telling me about.
Does the "NF" and the end of the casting number mean anything at all.
Does the "NF" and the end of the casting number mean anything at all.
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