my lil 6.1 died at the 1000ft mark at the track

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Buschi340 said:
Cross drilled? What does it mean exactly? I think it got that hot there because of a turned bearing. But that's just one of my 100 guesses...
Pics should show what exactly?
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Bearings only spin because the journal sticks to them from lack of lube.
Absolutely bolts can stretch, but I wouldn't necessarily say that's why the motor went.
It could have stretched when it slammed into the side of the block, or even from the hammering it took when the bearing spun causing clearance issue's before it actually let go and threw parts.

I have to agree with YR on this one, as it looks like a lack of lube.
 
ok, makes sense too. But if there is a oiling issue why only one this con-rod Journal? All other journals a more than fine, not even starting to wash out
 
I still think the piston exploded and that is why there are rings left in the bore. Discoloration might wipe off the rod, car craft just had blurb on how sometimes discolor end rods is just a coating and not actually something in the metal

But I don't think I am any kind of expert on this.
 
Don't remember if the 6.1 had floating pins. Had an LA 318 spit the circlip out. Got in between the rods. Messed up the oiling and tossed a rod. Hammered for five or so miles before saying goodbye. Differences forged and powdered metal rods. Rod journal on the 318 crank looked "dry" like yours.
 
yellow rose said:
The Rod looks blue to me. That means it ran out of oil.

Can you post some pics of the main bearing bores for us?

Also, did you verify the crank is cross drilled? If it is, can you take a thin screw driver and and stick it from the Rod bearing feed to the main journal? That will show how they did the cross drill, if they did cross drill it.
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Now I got you. I checked the crank and it is cross drilled on the main crank journals on 1,3,5. On 2 & 4 even 2 holes all the way through. The rod journals are fed from there. All holes are ok.
 
pulled the remaining Pistons and saw that the rod of cyl 2 is bend. No visible damages from impacts or similar. Piston top is ok and has no valve markings. Strange. Guess it got it ignition on the way up to TDC while the crank stopped reving for a nano second during the Situation on cyl 3 & 4...
 
Buschi340 said:
almost 6000rpm @100 mph
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is it possible that my speedhut tach was showing less rpms than i actual had? So I over reved the engine? for what reason ever max rpm of the engine shown was 6000 on the tach. maybe it was over 7000 in real? I had the rv limiter set to 6800 previously and i sounded like i hit it but Tach showed just 6000. strange, isn't it? maybe the tach is inaccurate in lets say 10 to 15%.

That can make a rod bearing spin, right? That can make the oil film on the bearings get lost?

I am still searching for reasons.
 
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