Finally pulled the motor to view the carnage...

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flyfish

flyfish

C8H18+N2O = :-D
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Well, its been a long time, but I finally stopped shunning my car for blowing up at the finish line and decided to pull the engine to see what broke 2 years ago. Here is the original thread if interested.

I think I’m done for the year….


I drained the oil and found lots of copper particulates in the oil filter (bearing material). I pulled the motor and opened it up yesterday to confirm my what I thought….broken connecting rod, #3. It broke the block as well. The bearing on the #3 rod was destroyed, so my guess its the bearing went first, which in turn caused the rod to snap. Now starts the long process of finding a new block, machining it, getting new rods, pistons, bla bla bla....Thanks the good Lord my heads are fine. One of the valves lightly kissed the top of the #3 piston, but nothing major. It looks like the crank will clean up fine too after turning it 10 thousandths.

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I didn't spray this motor, this one was NA.

The rods were Scat I-beams. I don't blame the rods, it was probably the bearing failure that started this whole mess. I built the motor in 2008. About 3 months prior to the motor expiring I had the engine out to replace a cracked oil pan...I checked all the bearings at that time and everything looked good....fast forward 3 months later (and about 7 races later) the rod let go somewhere north of 6000 rpm (in the 3rd round of a race). I checked all the bearings again on autopsy and the rest still look perfectly normal.
 
flyfish said:
I didn't spray this motor, this one was NA.

The rods were Scat I-beams. I don't blame the rods, it was probably the bearing failure that started this whole mess. I built the motor in 2008. About 3 months prior to the motor expiring I had the engine out to replace a cracked oil pan...I checked all the bearings at that time and everything looked good....fast forward 3 months later (and about 7 races later) the rod let go somewhere north of 6000 rpm (in the 3rd round of a race). I checked all the bearings again on autopsy and the rest still look perfectly normal.
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that is gonna be expensive. I see you're in Indy, what shop do you use up that way
 
dukeboy_318 said:
that is gonna be expensive. I see you're in Indy, what shop do you use up that way
Click to expand...
Not sure yet...in 2008 I had Indy Cylinder Head bore the block and order pistons for me....that was a fiasco...not sure if I'll go that route again. All I need is machine work on a "new" block, and someone to turn the crank and re-balance the rotating assembly. I will do the rest.
 
flyfish said:
Not sure yet...in 2008 I had Indy Cylinder Head bore the block and order pistons for me....that was a fiasco...not sure if I'll go that route again. All I need is machine work on a "new" block, and someone to turn the crank and re-balance the rotating assembly. I will do the rest.
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Cool, let me know when you find a place and how it works out if you dont mind. I'm looking for a new shop to correct my block. Do not use Cummings Engines in Bedford, period.
 
Bill Smith Motorsports in Muncie ind or Shorts Machine in Anderson ind. Indy cylinder heads good at yelling at you and not doing what you want....
 
Bought my SB 383 blown... three rods four pistons. Block and W-2 heads are ok even though every valve kissed a piston.... good luck.
 
Flyfish Sir,
That looks like a Hydraulic failure to me. Ask me how I know? Was there any evidence of water getting into that cylinder. The main reason I think this, is because the rod cap and crankshaft would be blue, from heat, had they failed first. Squeezing water will fold a connecting rod like that, faster than flailing around loose, from lack of a bearing.
Just my opinion, Sir.
 
Shifting at what rpm?
Did the block have any oiling mods done to it?
Sorry, style of cam?

I hope you get back up and running quickly. It sucks to be out for a spell.
 
sst3193 said:
Flyfish Sir,
That looks like a Hydraulic failure to me. Ask me how I know? Was there any evidence of water getting into that cylinder. The main reason I think this, is because the rod cap and crankshaft would be blue, from heat, had they failed first. Squeezing water will fold a connecting rod like that, faster than flailing around loose, from lack of a bearing.
Just my opinion, Sir.
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or detonation and it don't take much of that to do it . rods don't fail like that there was a cause .
 
sst3193 said:
Flyfish Sir,
That looks like a Hydraulic failure to me. Ask me how I know? Was there any evidence of water getting into that cylinder. The main reason I think this, is because the rod cap and crankshaft would be blue, from heat, had they failed first. Squeezing water will fold a connecting rod like that, faster than flailing around loose, from lack of a bearing.
Just my opinion, Sir.
Click to expand...

I did not see any evidence of water in the cylinder, but I will double check later tonight. The head gasket was intact, and there was not evidence of corrosion....but I'll double check and get back to you.

Thanks
 
That engine in my opinion did NOT fail due to a oiling issue, or a bearing issue.
 
flyfish said:
I did not see any evidence of water in the cylinder, but I will double check later tonight. The head gasket was intact, and there was not evidence of corrosion....but I'll double check and get back to you.

Thanks
Click to expand...
Nope, no evidence of water, head gasket was intact. I don't know...the rod could have folded from the years of abuse, then the broken piece of the rod hitting the block which the crank spinning caused the baring to get crunched (just speculation). Being a bracket racer, I have been known to Womp Womp Womp a few times...lol. I'm sure that didn't do it any favors.

Doesn't really matter to me, I'm just going to rebuild it....stronger and faster :)
 
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