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#1
03-16-2017, 12:04 AM
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First tear down in 50 years, block casting flaw?
Rebuilding a '67 400. Tore it down and pressure washed 50 years' worth of non-detergent oil scum off it. Bearings looked good, save for the camshaft bearings but I noticed what appears to be a crack in the very bottom of the cylinder and would like to know if it's a failure or just a casting artifact and if this means I need to do more testing before I spend more time and money on this block.
Thanks for looking! |
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#2
03-16-2017, 03:43 AM
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Just a casting thing no damage seen it quite a few times
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#3
03-16-2017, 06:43 AM
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Its all normal! Just grind and then polish them all out.
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#4
03-16-2017, 10:11 AM
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See that all the time. No worries.
__________________
Paul Carter Carter Cryogenics www.cartercryo.com 520-409-7236 Koerner Racing Engines You killed it, We build it! 520-294-5758 64 GTO, under re-construction, 412 CID, also under construction. 87 S-10 Pickup, 321,000 miles 99Monte Carlo, 293,000 miles 86 Bronco, 218,000 miles |
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#5
03-16-2017, 04:41 PM
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Looks like a particle of cast iron broke awar during machining.
I would smooth out that surface on the bottom of get rid of that imperfection in the cylinder wall and then build your 67 engine. 2 Bolt Main Engine???(Not drilled for 4 bolt mains?) Tom V. I have seen guys actually grind a small notch where the break-away was and the block is just as strong as before when the piston is at bottom of the bore.
__________________
"Engineers do stuff for reasons" Tom Vaught Despite small distractions, there are those who will go Forward, Learning, Sharing Knowledge, Doing what they can to help others move forward. |
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#6
03-17-2017, 06:22 AM
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The main thing to do so that this area does not produce the start of a crack under load is grind out the start of that casting seam notch at the point where it stars up on the cylinder wall.
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#7
03-17-2017, 06:47 PM
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Yea, seen that a bunch of times, and each time no crack. Worth a grinder blend.
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