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-   -   Has Anyone Seen this Defect in a Forged 4.50” stroke Crankshaft? Pics inside (https://forums.maxperformanceinc.com/forums/showthread.php?t=857163)

Pontiac Derek 03-08-2022 10:45 PM

Has Anyone Seen this Defect in a Forged 4.50” stroke Crankshaft? Pics inside
 
2 Attachment(s)
So this is a new one for me and puts a Damper on my build for a little bit, there is a void in the Chamfer of #6 rod journal and it goes into the oil passage!!! WTH? I thought being forged this would not or really could not happen?
If I hadn’t somehow seen this and just thought it was odd before I started inspecting it real close and realizing it was an actual hole this could’ve easily blown at my engine I got real lucky!!!

rod cole 03-09-2022 12:11 AM

Just curious does the drilling make it to the main? Whos crank.

Pontiac Derek 03-09-2022 12:16 AM

Quote:

Originally Posted by rod cole (Post 6324959)
Just curious does the drilling make it to the main? Whos crank.

It does go through like it should, there is a void between the internal passage and the Chamfer

ID67goat 03-09-2022 05:38 AM

Did you get this crank from eBay? It is probably a factory blem crank that the vendor passed on to you as a normal part.

Have you contacted the seller about it? My guess is that this crank garbage and probably not worth putting money into repairing. You would probably be better off getting another one.

charlie66 03-09-2022 07:25 AM

Wow . I've never seen that ..

25stevem 03-09-2022 07:41 AM

If that’s a cast crank then don’t even think about using it!
If it’s forged you could get it welded and recut, but I would still have a big concern that the oil passage was misdrilled enough to not intersect as it should with the other one.
It looks like it could be up to 1/8” off from where it should be!

Pontiac Derek 03-09-2022 10:42 AM

Quote:

Originally Posted by 25stevem (Post 6324996)
If that’s a cast crank then don’t even think about using it!
If it’s forged you could get it welded and recut, but I would still have a big concern that the oil passage was misdrilled enough to not intersect as it should with the other one.
It looks like it could be up to 1/8” off from where it should be!

Forged 4340 3.00 main 4.50 stroke, yeah I’m concerned it might not be repairable, I am getting it exchanged

Pontiac Derek 03-09-2022 10:45 AM

Quote:

Originally Posted by ID67goat (Post 6324988)
Did you get this crank from eBay? It is probably a factory blem crank that the vendor passed on to you as a normal part.

Have you contacted the seller about it? My guess is that this crank garbage and probably not worth putting money into repairing. You would probably be better off getting another one.

Yes, and yes, Vender wants me to pay the 128$ shipping again! They told me to keep the crank, I don’t think I should have to pay the shipping again, by that time I would have bought a nicer crank, I need to see if it’s even worth repairing, probably not

mgarblik 03-09-2022 12:57 PM

That breakthrough is rather frightening in the fillet area. So one of several things may have caused this. 1. Incorrect set-up for drilling. (unlikely IMO). 2. Drilling with a dull drill bit, (possible) 3. Hitting some crap or inclusion while drilling sending the bit off track (possible). 4. Improper index when drilling was started (possible). IMO, that crankshaft is a throw away. Only real way to know where the various drillings are placed would be to X-ray the crank. How many other drillings are .010" or .005" away from breaking through elsewhere in the crankshaft? Great catch on your part! I would be concerned using anything from this vendor. For Chinese forgings, my choice would be Molnar, Scat, Eagle in that order.

Pontiac Derek 03-09-2022 01:06 PM

Quote:

Originally Posted by mgarblik (Post 6325067)
That breakthrough is rather frightening in the fillet area. So one of several things may have caused this. 1. Incorrect set-up for drilling. (unlikely IMO). 2. Drilling with a dull drill bit, (possible) 3. Hitting some crap or inclusion while drilling sending the bit off track (possible). 4. Improper index when drilling was started (possible). IMO, that crankshaft is a throw away. Only real way to know where the various drillings are placed would be to X-ray the crank. How many other drillings are .010" or .005" away from breaking through elsewhere in the crankshaft? Great catch on your part! I would be concerned using anything from this vendor. For Chinese forgings, my choice would be Molnar, Scat, Eagle in that order.

Yeah I barely caught it, it is an actual void in the metal, it’s actually a little ways off from the drilled oil hole, which is scary because if it’s not from the machining process it’s a bad forging process or the material wasn’t pure? Idk it’s a SGI crankshaft, I’ve had good luck with them until now

mgarblik 03-09-2022 02:15 PM

I understand what you are saying. But it must be pretty close if you can poke a wire through the fillet from the oil hole? Star Galaxy Forgings have been decent as you stated. Hopefully the replacement will be good to go. You might want to try and negotiate some compromise on the replacement shipping.

charlie66 03-09-2022 07:16 PM

So much for quality control .

That's not your fault. You shouldn't have to pay anything...

I hope it works out for you Good luck...

Pontiac Derek 03-09-2022 08:44 PM

[QUOTE=charlie66;6325189]So much for quality control .

That's not your fault. You shouldn't have to pay anything...

I hope it works out for you Good luck...[/QUOTE

Yeah no kidding!!! I don’t have a lot of time though so I think what I’m gonna do is do like they said and just keep this Crankshaft find somebody who knows what they’re really doing and see if it can be repaired if they can grind it out weld it back up and then re-grind it I don’t know and then get the new crank so I guess that’s some consolation but still I would’ve just bought a nicer Crankshaft if I had all this extra money to spend on shipping

Jim Zeek 03-09-2022 08:54 PM

[QUOTE=Pontiac Derek;6325213]
Quote:

Originally Posted by charlie66 (Post 6325189)
So much for quality control .

That's not your fault. You shouldn't have to pay anything...

I hope it works out for you Good luck...[/QUOTE

Yeah no kidding!!! I don’t have a lot of time though so I think what I’m gonna do is do like they said and just keep this Crankshaft find somebody who knows what they’re really doing and see if it can be repaired if they can grind it out weld it back up and then re-grind it I don’t know and then get the new crank so I guess that’s some consolation but still I would’ve just bought a nicer Crankshaft if I had all this extra money to spend on shipping

how long ago did you buy it? who is the vendor. file complaint with credit card company. $128.00 is cheaper than a 7-10k engine

turbo69bird 03-10-2022 12:26 AM

Wow I was just about to buy a rotating assembly w a forged crank and now I’m. Completely second guessing it over my factory Pontiac stuff that thing is a POS and I’d never pay them the $128 I’d charge them for my wait time. I’d keep it to make a lamp or something but it would NEVER go in one. Of my engines . That’s crazy, too much to lose Just my .02

Pontiac Derek 03-10-2022 12:48 PM

[QUOTE=Jim Zeek;6325216]
Quote:

Originally Posted by Pontiac Derek (Post 6325213)

how long ago did you buy it? who is the vendor. file complaint with credit card company. $128.00 is cheaper than a 7-10k engine

It’s an SGI crankshaft from EBay, they are sending me another one, even though this is an all iron low rpm deal if I didn’t catch that it for sure would have eventually smoked the bearings or broke, I will be having the next one thoroughly checked out!

Dave Polichena 03-10-2022 01:38 PM

[QUOTE=Pontiac Derek;6325350]
Quote:

Originally Posted by Jim Zeek (Post 6325216)

It’s an SGI crankshaft from EBay

Why not support our Pontiac Vendors? This probably would not have happened.

Pontiac Derek 03-10-2022 01:57 PM

5 kids, mortgage, awaiting a major back surgery, So I can either build my engine on the budget I have or I could not do it at all with my personal situation anyways now if you can’t understand that I don’t know what to say I’m sorry I didn’t buy from your favorite vendor


QUOTE=Dave Polichena;6325363]
Quote:

Originally Posted by Pontiac Derek (Post 6325350)

Why not support our Pontiac Vendors? This probably would not have happened.



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