2011 Case Crack please review pics and offer suggestions . . . Thanks!

The good news is I decided to do a late season tear-down to swap out the piston and inspect the connecting rod.  Wobble on the rod indicated time for a change.  

 

I would appreciate any advice for a new rod or crank assembly.  I was thinking Hot-Rods crank, but I hear 2012 0EM is a good choice as well.  All bearings will be replaced, too.  Wide open for suggestions on this.  Brand/Vendor, etc.  I know there have been some rebuilds of late, so please let me know if you found a good deal.

 

The bad news is, there is a crack that is not supposed to be there.  I took 3 pictures for you to look at.  The first shows the crack in the right exhaust side of the case and the second is a close-up.  The third picture is the opposite side, where some stressing is evident.  I have not seen this before.  So, if you ran into this, what would  be your thought process?  Opinions on how this could happen would help as well.  I appreciate your input.  

 

Here is the surprise I found:

 

CASECRACK1_zpsb7402e74.jpg

 

Here is a close-up:

 

CASECRACK2_zps634e1f60.jpg

 

Here is the opposite side (left exhaust side) some stress is apparent:

 

CASECRACK3_zps30209fd5.jpg

 

Thanks again for looking.  Let me know your thoughts.  Thank you.

 

 

 

 

 

 

 

 

Did you clean this up? Have you been into this engine before? If so, was the "crack" there before? Looks like a casting flaw to me. Unless it wasnt there last time.

I'd continue with your plan and run it.

Did you clean this up? Have you been into this engine before? If so, was the "crack" there before? Looks like a casting flaw to me. Unless it wasnt there last time.

 

No clean-up.  This is exactly what it looked like a couple of hours ago when I pulled the cylinder off.  I did change the piston last fall, and I don't remember seeing anything there before, but that doesn't mean it wasn't there.  It will be interesting to see what the other side looks like when I take the right cover off.  Very much appreciate your feedback.  

I'd continue with your plan and run it.

Classy.....

 

 

 

The only thing I can think of right now that could induce stress there would be side loading of the crank from the "rod wobble" as you put it, and any vibrations caused by that.

 

Bummer, looks like new cases are in order on top of that full rebuild.

Edited by Joshx221

Get a Moose rod (its a repacked carillo) new OEM big end pin and bearing. Have it put on your stock crank halves. Most reliable setup without spending HUGE money. Also, keep the 11 crank halves in there they are lighter than the 12's, and will allow the motor to rev up a bit quicker.

Made the run it comment based on 25 years of diagnostic automotive experience. I have seen marks like this in the castings of many engines. If the metal is in fact cracked and moving under load there will be some fine particles piled up around the so called crack.

Classy.....

 

 

 

The only thing I can think of right now that could induce stress there would be side loading of the crank from the "rod wobble" as you put it, and any vibrations caused by that.

 

Bummer, looks like new cases are in order on top of that full rebuild.

 

Come on, Josh!  I was waiting for you to tell me everything is OK.  

 

Not really, of course.  I could see that happening due to wobble.  Interesting that the motor ran smooth as silk, or seemed to.  Wonder if way over-jumping a table-top (can't believe he held on) could have transferred too much stress to the engine as part of the frame structure?  I'm no engineer, but I hear there are some out there . . . 

Made the run it comment based on 25 years of diagnostic automotive experience. I have seen marks like this in the castings of many engines. If the metal is in fact cracked and moving under load there will be some fine particles piled up around the so called crack.

 

It's all good.  I appreciate the observation.  I am sure I will learn more about this anomaly when I pull the thing apart.  Thank you very much for your input.

Get a Moose rod (its a repacked carillo) new OEM big end pin and bearing. Have it put on your stock crank halves. Most reliable setup without spending HUGE money. Also, keep the 11 crank halves in there they are lighter than the 12's, and will allow the motor to rev up a bit quicker.

 

Good info dmm, thank you!  

OK well thank you for your input pomoco, Josh and dmm. Here is the other side of the story. The green circle is the opposite side of the crack. The red arrow points to a number of imperfections that resemble the crack. At first, I was very concerned about the imperfections pointed out by the arrow, but then I considered the pristine condition of the area circled in Green. This is the area exactly opposite the crack.

My original thinking was supported by Josh. Best to be conservative on matters of structural integrity. Nobody wants to have to buy new cases, but at just over $300 or so, if you are doing the labor yourself and replacing everything anyway, it's better than risking failure on the face of a triple. That could cost more than anyone would be willing to pay.

Pomoco pointed out that he had seen flaws like this before in 25 years of diagnostic experience. I have been working on bikes for a long time, too, but I have never seen anything like this in what I would consider to be a critical area. It turns out, there is a lot structural support in this area, and no evidence of stress at all on the other side. It also seems that similar looking imperfections are all over the outside corners of this case. I could see where casting imperfections could appear bad, yet be perfectly fine. I hope that's the case here.

Of course, I haven't split the cases yet. Busy weekend. I will take a another careful look when the cases are split, but I think I may be OK here. If I am way off base, I know you will let me know. Thanks very much and have a great week!

7265badf-bad5-444b-a849-b58b6289d5a7_zps

Edited by Dragon67

Those are casting imperfections. A real crack is really bearly visable. These castings are full of small "Flaws"  that show up when pouring the aluminum in.

Those are casting imperfections. A real crack is really bearly visable. These castings are full of small "Flaws"  that show up when pouring the aluminum in.

Thanks Al. Never saw anything like it before. I appreciate the reassurance.

I do a lot of Mechanic work on Aluminum blocked import engines, and these crack look a likes are all over the place. Gets confusing sometimes,

Boy these pictures look way better on my computer than my phone. That said one thing that still concerns me is I see an oil jet near by. As long as the flaw doesn't cause the oil to leak by than I guess you would be fine. I would figure out a way to pressurize the oil system on that case half and see if there is any leakage. Maybe coolant too, but I would figure you would have seen a coolant loss.

Boy these pictures look way better on my computer than my phone. That said one thing that still concerns me is I see an oil jet near by. As long as the flaw doesn't cause the oil to leak by than I guess you would be fine. I would figure out a way to pressurize the oil system on that case half and see if there is any leakage. Maybe coolant too, but I would figure you would have seen a coolant loss.

I hear you it looks scary, casting flaw or not. I'm going to take a much closer look tomorrow. Thanks bud.

Did you clean this up? Have you been into this engine before? If so, was the "crack" there before? Looks like a casting flaw to me. Unless it wasnt there last time.

 

I failed to update this thread with a conclusion  :lame: These scary looking "cracks" are exactly what you said they were.  The motor has been running strong since I put it back together.  Thanks very much again.  :thumbsup:

It is a casting flaw. It has not gotten worse. Forget about it.

Come on, Josh!  I was waiting for you to tell me everything is OK.  

 

Not really, of course.  I could see that happening due to wobble.  Interesting that the motor ran smooth as silk, or seemed to.  Wonder if way over-jumping a table-top (can't believe he held on) could have transferred too much stress to the engine as part of the frame structure?  I'm no engineer, but I hear there are some out there . . .

 

This was the post I was talking about.

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