No Fun Here...
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Ok... This is weird. I just pulled the intake and the head and I was right but can't figure it out. Number 2 piston has a hole in it. There is no damage to the cylinder and it measures within 4 thou of stock. It looks like a clean hole...
Any ideas?
Any ideas?
Racer
Joined: Jan 2015
Posts: 293
Likes: 43
From: Vernon B.C.
What does the cylinder head look like on that chamber? Does it have any marks from something getting in there? The two dents above the hole looks like something got in there. Beautiful car by the way! I`m partial to 69 427s!
Race Director
Joined: Dec 1999
Posts: 11,094
Likes: 990
From: Sierra Foothills CA
My thoughts exactly. The imprints look to be the same size as the hole, so something got in there and bounced around. You may find it in the crankcase.
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Looked at the head. Same marks in the same place... Ah geeze.
At least it is going to come to a happy ending as it is rebuildable without much fuss although it will probably get quite a bit of that. After pulling the head, I'm a pretty happy camper as I figured the numbers block was gone only to find it is still within original factory specs. Smile on my face.
Drifting
Joined: Mar 2001
Posts: 1,395
Likes: 6
From: Indiana
Oh, and how ya doing, Les?
Racer
Joined: Jan 2015
Posts: 293
Likes: 43
From: Vernon B.C.
Still sucks though as it looks like it was running pretty good judging from the pictures. Make sure to check that head for cracks when you rebuild it. It should be ok but I`d rather be safe than sorry...
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Thanks Les. I'm going to pull the pan tomorrow as whatever caused the hole will be in there... I'm hoping its a piece of a valve and not me dropping a bolt down the pipe. How bad would that be to live down?
Safety Car
Joined: Sep 2005
Posts: 4,213
Likes: 643
From: Orange County Ca
The #4 piston has a dimple in the top below the dome also. Do all your pistons have this?
My 69 390hp had the same pistons, but no dimples.
Could this have been a attempt to balance them?
My 69 390hp had the same pistons, but no dimples.
Could this have been a attempt to balance them?
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Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Going for the full meal deal and spend some time on it. Just going with stock but it will be impressive. What made me happy was pulling the head and not only seeing no block damage but seeing no ridge or any wear. You could clean this thing up with a hone but that isn't the way it's going to go. It's a late build 69 (Oct 24) and the block was used on late 427's and 70 454's. Casting is 3968512. I still can't figure what would punch a clean hole like that in a piston. I even pulled the exhaust pipes to see if there were any parts.... The pan will be off tomorrow.
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Mine have that dimple on the lower part of all pistons but the hole is on number 2 at the top. It isn't a burn hole. It looks like a factory drilled hole but it isn't.
Safety Car
Joined: Sep 2005
Posts: 4,213
Likes: 643
From: Orange County Ca
It does seem odd that the hole is directly across from the lower dimple. I thought maybe a ball bearing got down the carb, but could it get punched through with out cracking the piston top? Pretty weird.
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Race Director
Joined: Dec 1999
Posts: 11,094
Likes: 990
From: Sierra Foothills CA
I will pull the pan in the morning and that should tell the story. I am pretty careful with this old car and didn't drop anything down the intake but obviously something is in there. When it blew up I hadn't had the top off in over a month. I have a good ear so would have noticed if something was rattling around in there. The hole looks like it was drilled or punched. I used to own an engine shop in my younger days and have never seen a perfect hole like this. I will let you know when I pull the pan and hopefully it isn't my mistake... If it is, will you guys back me up and try and convince my wife to not put a hole through me ? Again?
Very happy to hear that the block looks so good. 
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
That could be Tom- strange one here and I'm curious to hear what he finds. I've been good, thanks. Just living the dream...or at least as close as I can get to it. I hope you and the family are doing well.
Hey, even if you find something incriminating, there's no full disclosure requirement here at the forum- if you signed on for full disclosure with the wife you're on your own there! Very happy to hear that the block looks so good.
Hey, even if you find something incriminating, there's no full disclosure requirement here at the forum- if you signed on for full disclosure with the wife you're on your own there!
Very happy to hear that the block looks so good. 
Terrorizing Orange Cones
Joined: Oct 2007
Posts: 2,572
Likes: 17
From: Northern CO
We empathize with you, C-G. These old cars are like a cherished family member to many of us.
Regarding your discovery: the combustion chamber reflects something round, like a ball bearing as opposed to a bolt or machine screw. It seems that any Grade 5 or 8 threaded fastener would have left sharper marks/gouges on impact.
Hard as it was to realize the loss of that cylinder, you may have dodged a bullet when the culprit punched through the piston's top, as opposed to scarring that cylinder's wall and causing more catastrophic damage to the block.
Considering how many rpms each piston cycles, whatever it was, happened very quick to leave so few marks before heading towards the sump.
I've seen wadcutter ammo that left nearly that same clean hole in paper. Sure am curious to what you can locate to show us.
A reputable machine operator should have practice on shaving the deck without cutting down the embossed pad information. Be sure that they convince you of that practice before leaving your priceless case with them.
Good luck and thanks for sharing.
Regarding your discovery: the combustion chamber reflects something round, like a ball bearing as opposed to a bolt or machine screw. It seems that any Grade 5 or 8 threaded fastener would have left sharper marks/gouges on impact.
Hard as it was to realize the loss of that cylinder, you may have dodged a bullet when the culprit punched through the piston's top, as opposed to scarring that cylinder's wall and causing more catastrophic damage to the block.
Considering how many rpms each piston cycles, whatever it was, happened very quick to leave so few marks before heading towards the sump.
I've seen wadcutter ammo that left nearly that same clean hole in paper. Sure am curious to what you can locate to show us.
A reputable machine operator should have practice on shaving the deck without cutting down the embossed pad information. Be sure that they convince you of that practice before leaving your priceless case with them.
Good luck and thanks for sharing.
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Thread Starter
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
We empathize with you, C-G. These old cars are like a cherished family member to many of us.
Regarding your discovery: the combustion chamber reflects something round, like a ball bearing as opposed to a bolt or machine screw. It seems that any Grade 5 or 8 threaded fastener would have left sharper marks/gouges on impact.
Hard as it was to realize the loss of that cylinder, you may have dodged a bullet when the culprit punched through the piston's top, as opposed to scarring that cylinder's wall and causing more catastrophic damage to the block.
Considering how many rpms each piston cycles, whatever it was, happened very quick to leave so few marks before heading towards the sump.
I've seen wadcutter ammo that left nearly that same clean hole in paper. Sure am curious to what you can locate to show us.
A reputable machine operator should have practice on shaving the deck without cutting down the embossed pad information. Be sure that they convince you of that practice before leaving your priceless case with them.
Good luck and thanks for sharing.
Regarding your discovery: the combustion chamber reflects something round, like a ball bearing as opposed to a bolt or machine screw. It seems that any Grade 5 or 8 threaded fastener would have left sharper marks/gouges on impact.
Hard as it was to realize the loss of that cylinder, you may have dodged a bullet when the culprit punched through the piston's top, as opposed to scarring that cylinder's wall and causing more catastrophic damage to the block.
Considering how many rpms each piston cycles, whatever it was, happened very quick to leave so few marks before heading towards the sump.
I've seen wadcutter ammo that left nearly that same clean hole in paper. Sure am curious to what you can locate to show us.
A reputable machine operator should have practice on shaving the deck without cutting down the embossed pad information. Be sure that they convince you of that practice before leaving your priceless case with them.
Good luck and thanks for sharing.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
Hole in the piston. Hope the block is good.
Now you have an excuse to build it bigger and better. Totally stock, numbers matching exterior. 4.280 Bore and 4" stroke, internal balance, Pocket port heads, Roller cam. 460 CI, an extra 100 hp and no one will ever know. It is a beautiful car.
Now you have an excuse to build it bigger and better. Totally stock, numbers matching exterior. 4.280 Bore and 4" stroke, internal balance, Pocket port heads, Roller cam. 460 CI, an extra 100 hp and no one will ever know. It is a beautiful car.
Last edited by 63mako; Apr 2, 2015 at 11:12 PM.