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Drunk and Disorderly
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The clearences were to tight. It was a new engine with only 7 runs, the builder refuses to even talk to me about it, so I have splashed these pics all over the local boards, and made sure everyone knew who built it. I diden't ruin him, but I shure took a big chunk out of his busness. Next time I have the pistons out I will take some pics of the pistons and some better pics of the crank. I put my spare engine in and promptly knocked the bearings out of it last weekend :smt102, so I am just putting it back together now.





 

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It don't look good

Bear.. can you take a top pic of that rod/bearing? It almost looks like standard bearing were used on a crank with thats should have had short or chamfered bearing to clear the radius on the crank.
Just try to help my playing Dick Tracy, now where is my decoder ring anyway?
 

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did the piston tag the head ? What was the quench distance ?Rod failure looks like a mechnical bind.


 

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Drunk and Disorderly
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Yes the piston did tag the head, but did very little damage. The picture there shows the Crower HIPPO lifter took a hit and split the roller. In this pic you can see where the pistion rotated slightly and ragged the head below the spark plug and on the other side below the valve. I am not sure of the quench. It bent slightly both valves




 

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I wonder if the piston was tall in that hole. I do not see detonation,preignition or even oil tattles anywhere in the motor from the pictures you have provided. Hell the crankshaft will normally blue up nicely when it is an oiling issue provided the rest of the motor pistons etc look good. . If the piston tagged the head it could have easily tweaked the rod and started the domino effect of fialure.

Can you find a machnist to check to see if the deck is square to the crankshaft saddles ? If the block was milled a little bit off it could add up to no clearance at one end of the motor.


Yes the piston did tag the head, but did very little damage. The picture there shows the Crower HIPPO lifter took a hit and split the roller. In this pic you can see where the pistion rotated slightly and ragged the head below the spark plug and on the other side below the valve. I am not sure of the quench. It bent slightly both valves




 

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That is why I asked him to get the deck to crankshaft saddle quaring checked out. If the deck surface it running tall on one end and short on the other that would explain the rod fialure. Once the rod bends the bolts will fial mostly due to sheering loads.

That piston was hitting that head, many revolutions before it expired.

Now the question becomes, was it a fastener failure on the rod, or incorrect assembly/tolerance stack up.
 

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I would call Mile high crankshaft in Denver Colorado
I had similiar engine damage done to my crank it is a crower 4 hole indura a little pricy just to junk. Apparently this guy fix top fuel stuff all the time as well. My Engine guy Ken Murray Of Winnipeg MB he's in Canada's drag racing hall of fame says he can't believe how well it came out.
 
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