HELP! Drilled too far to remove broken flywheel bolt
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HELP! Drilled too far to remove broken flywheel bolt Hoping I am OK, but I am thinking I am not 
F*(K
Ended up snapping one of my crank bolts, don't even ask how. Fail #1. Drilled for an EZ-Out, which was too small for the job, and right as I was thinking I should back it out and go 1 size larger, I snapped it off. Fail #2. Ended up actually being able to drill a bigger hole back through the bolt (was amazed it actually worked with the broken EZ out in there), but then noticed my completely moronic *** drilled too deep and got into the block behind the crank! Epic Fail #3.
I'm not sure where to go from here now. Rough measurements -
Face of crank to non-effed up block surface: ~7/8"
Face of crank to the bottom of my dumbass hole: ~1-3/8". Drill bit diameter is 3/16".
So, I basically have a f*(king 3/16" dia, .5" deep hole in the back of my block, right?
How thick is the block at the rear of the engine?
What's behind the crank there? Isn't it the reluctor wheel?
What happens if there IS a hole right though the block?
Is there an oil galley or anything back there? Can I start the engine with no flywheel to see if I have any leaks?
Any other advice? I absolutely cannot believe I did this. Such a ridiculously dumbass move, and I am guessing, a very expensive mistake now.
F*(KEnded up snapping one of my crank bolts, don't even ask how. Fail #1. Drilled for an EZ-Out, which was too small for the job, and right as I was thinking I should back it out and go 1 size larger, I snapped it off. Fail #2. Ended up actually being able to drill a bigger hole back through the bolt (was amazed it actually worked with the broken EZ out in there), but then noticed my completely moronic *** drilled too deep and got into the block behind the crank! Epic Fail #3.
I'm not sure where to go from here now. Rough measurements -
Face of crank to non-effed up block surface: ~7/8"
Face of crank to the bottom of my dumbass hole: ~1-3/8". Drill bit diameter is 3/16".
So, I basically have a f*(king 3/16" dia, .5" deep hole in the back of my block, right?
How thick is the block at the rear of the engine?
What's behind the crank there? Isn't it the reluctor wheel?
What happens if there IS a hole right though the block?
Is there an oil galley or anything back there? Can I start the engine with no flywheel to see if I have any leaks?
Any other advice? I absolutely cannot believe I did this. Such a ridiculously dumbass move, and I am guessing, a very expensive mistake now.
I would imagine that if you did drill thru the block you could just thread the hole and install a plug. Or a regular press style freeze plug for that matter. If you hit an oil galley and went all the way thru then that would be a bit more complicated but doable. Let's just hope you didn't.
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maybe I can find a small set screw and thread it into the block...
Edit: And, yeah - dumb question. Of course I can't start it with the flywheel off....
Edit: And, yeah - dumb question. Of course I can't start it with the flywheel off....
Last edited by Atrus_SS; Jun 14, 2013 at 10:51 AM.
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No worries man, I am downright sick to my stomach about this ridiculously embarassing eff up.
In case anyone else is as dumb as me, here was my fix - we'll see if it works...
Got a stainless set screw - M6x1.25. I think it's about 1/4" long. I tapped the hole I drilled, and then applied threadlocker to it (lock-tite red) and threaded it in until it was just barely recessed from the face of the block - maybe recessed .5mm-1mm.
In case anyone else is as dumb as me, here was my fix - we'll see if it works...
Got a stainless set screw - M6x1.25. I think it's about 1/4" long. I tapped the hole I drilled, and then applied threadlocker to it (lock-tite red) and threaded it in until it was just barely recessed from the face of the block - maybe recessed .5mm-1mm.
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Atrus SS... Your not stupid, it was a mistake and mistakes happen. live and learn as they say.
" a genius learns from others mistakes, a smart man learns from his own mistakes". I am the latter.
" a genius learns from others mistakes, a smart man learns from his own mistakes". I am the latter.
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I know, I am just hard on myself - if it were something minor, I wouldn't get all up in arms. Drilling a hole through my block, especially in a basically inaccessible place...
Trans is in..working on the MC, and then just install the shifter and driveshaft and hopefully i'll have good news.
Trans is in..working on the MC, and then just install the shifter and driveshaft and hopefully i'll have good news.
the rear cover just unbolts ,all you have to do is pull off the flex plate or flywheel and take out the 10 bolts and pull it off, auto parts stores have it in stock . Plus you'll be changing the rear main seal
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Can I get a further out pic, so I can see where in relation the damage is? The main cap is there. Did you drill into the cap? The block? A cap bolt passage? This really sucks, but depending on where it's at, I agree you could likely just tap and install some sort of plug.
Looking at the first pic you posted it appears you drilled into one of the main cap bolts. Looking at your fix you'll probably be okay if the metal shavings don't go through the oil pump and the bolt still holds
If you ever have anything like this happen again, just get a left handed drill bit. As you drill use a lot of pressure and the bit will usually grab. When it does, the bolt most likely will screw itself right out.