Snapped starter bolt inside engine

Auto Doc's said:
If you know any experience auto mechanics, they might be able to help you with this. Usually a center punch, a drill and a 1/8" left-hand drill bit will get these broken bolts out without too much effort. I do not recommend trying to MIG weld a nut to the broken portion because EMF from the welder will ruin the stator and voltage regulator.

Most modern small engine shops are not equipped to handle a broken bolt in an aluminum engine block. They often just want to replace the engine because they do not have any experience with these problems. A small independent automotive shop might be a better choice because they deal with broken manifold bolts on a fairly regular basis.
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RevB said:
Aaaaand....I'll wager that the old starter is just fine only needing disassembly, cleaning the commutator, and inspecting the brushes and reassembly.
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the old starter worked but the shaft had lateral play so I'm assuming the bearings were worn. I got a new OEM starter for I think $146
 
bigjake said:
@Auto Doc's, @StarTech Well, I think I may have had some divine intervention. I was surprisingly able to back the broken bolt out with just a screwdriver. I had torqued it so much, that I was sure it had to be pretty stuck in there. I guess the shock of the bolt snapping must have jarred it loose. I picked up 2 new 8.8 bolts to replace them both. I can hand thread the new bolts in almost all the way and they seem snug. I was thinking I would put blue thread lock on the new bolts just in case I did any damage to the threads with the over tightening. Good idea?
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You did get very lucky bro!!!
 
bigjake said:
My gut was telling me to stop tightening, as it seemed well beyond adequate, but the steel bolts were still turning fairly easily in the aluminum engine and then SNAP
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There was your first red flag. Aluminum engine. Easy on the torque.

I too have bad eyes. Really didn't need a torque wrench on starter bolts. Worst case the bolts fall out. A 3 dollar fix at any hardware store. Compared to say a machine shop bill.

Next time, use your weak hand and a ratchet. If you are normally right handed, use your LEFT. Your left is weaker as we all know. This weaker hand will lessen applied torque. You can even open a finger or two on your grip to lower torque.

Also if you are concerned about over torquing, use less torque and apply thread locker. Stop turning when the screw stops and let the thread locker do its job.

Glad to hear you got the threads out. Nice job congrats.
 
I have done this. Use a punch perpendicular to the angle and make a punch mark. Use a good quality drill about 2/3 - 3/4 of the bolt diameter. Then start drilling at an angle until you get a small hole. Then straighten the drill and make the hole. Check the other bolt to see if it leaves a space under the bolt. Then drill through the broken bolt. Use an easy-out to remove the broken bolt. Otherwise, go just deep enough for the easy-out to go in without bottoming out. You may have to use a hammer to tap the easy-out to get a good start... Good luck. If the threads look a little damaged after bolt comes out, see how deep the hole is and if it has good threads at the bottom of the hole. If there are good threads more than a quarter inch, use them by getting a longer bolt and cutting it to a length that matches the hole depth. Just have to make sure it doesn't bottom out when tightening. Hand tighten to a little more than snug and check on it now and then. I did this on a boat motor that had one stripped bolt hole in aluminum. The hole was a half inch deeper than the old bolt but had good threads to the bottom. Make use of them. I never had any problems after that. Did it another time on a carburetor hole. Just check to make sure it stays put.
 
bigjake said:
@Auto Doc's, @StarTech Well, I think I may have had some divine intervention. I was surprisingly able to back the broken bolt out with just a screwdriver. I had torqued it so much, that I was sure it had to be pretty stuck in there. I guess the shock of the bolt snapping must have jarred it loose. I picked up 2 new 8.8 bolts to replace them both. I can hand thread the new bolts in almost all the way and they seem snug. I was thinking I would put blue thread lock on the new bolts just in case I did any damage to the threads with the over tightening. Good idea?
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You Lucky Dog! You best buy some Lotto Tickets, I've very rarely had to do less than a left hand drill. Instead of Locktite, I'd be using Anti-Seize because of dissimilar metals.
 
Nice a story with a happy ending! Thanks for sharing, It serves as a good reminder to be more careful when using my torque wrench that has VERY difficult to see settings on a shiny chrome surface.
 
This would be hard to do with such a small diameter bolt, but using a punch on the outside edge of the broken bolt and tapping with a hammer to reverse the bolt out sometimes works, especially when the bolt isn't stuck in the threads by corrosion (or blue Loctite).
 
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