Better way to drill out snapped bolts?

[jimchere]

Okay, was wondering if anyone can help me out here. I'm replacing the shocks on my '98 Cherokee (just turned 100k miles). Front ones went easy. Not so with the rear. Two bolts hold each shock at the top into the Jeep's frame/body, with one big bolt at the bottom axle mount. On the rear shocks, all four of the top bolts snapped off like butter . I finished replacing the left rear yesterday, by drilling out the 9mm bolts that snapped, and retapping the hole to 3/8-16 and installing new grade 8 bolts. Now I'm about to tackle the other side. Problem is, even with a good quality cobalt drill bit, the left side took FOREVER (or so it seemed..about 2 hours to drill out each bolt). Is there a better way? Or do I just need to lay underneath the darn thing for another 4 hours with a drill and continue the excellent workout on my triceps? Can't do anything with torch/fire because its too close to the gas tank. Any tips, or tool I can get at "Ace or some other place" to make the job a little easier (and add another tool to my garage ) would be appreciated. I only buy quality tools, preferable USA made.

 

[flashback]

Re: Better way to drill out snapped bolts?

Hi Jim, There are a couple of choices that MAY work better. One is an eazy out, which involves drilling a smaller hole in the center of the bolt, then running the eazy out into the hole and remove the broken bolt by unscrewing it.. the other is a left handed drill bit which will, in some cases, remove the bolt as you drill the bolt. Oh, and soak the bolts with penetrating oil ahead of time, it helps...good luck

 

[ob]

Re: Better way to drill out snapped bolts?

I'm afraid it'll have to be more of the same.Just drilled out two over torqued spindle studs myself last week on the front of my daughters vehicle.Too bad some of that good ole USA engineering wasn't put into your Jeeps rear shock mounting bolts.

 

[one more cast]

Re: Better way to drill out snapped bolts?

TIP: Make sure you keep the drill bit well lubed with cutting fluid, oil, or even kerosene.

 

[lakelivin]

Re: Better way to drill out snapped bolts?

Originally posted by flashback:<br /> ..... Oh, and soak the bolts with penetrating oil ahead of time, it helps...good luck

Have read here that the type you use can make a big difference. As I recall people swear that something like PB Blaster or SeaFoam works MUCH better than WD-40 or Liquid Wrench. No experience myself, gonna pick up one or the other next time I'm at an auto supply store.

 

[dolluper]

Re: Better way to drill out snapped bolts?

Use more drill bits start small and work your way up to the almost bolt size goes much faster ,keyless chuck ideal for the process

 

[jimchere]

Re: Better way to drill out snapped bolts?

Thanks everyone for the tips. Finally got the last sucker out. Tried using a reverse (CCW) extractor on the drill....no go. It did cut just enought to allow a 1/8(I think) cobalt bit to dig in and cut through, then followed up with a 5/16. Ready for the easy part to tap 'em out and replace with 3/8-16! FYI, I'm a big fan of PBlaster, which has gotten me out of some tough binds in the past. In this case, however....no go. Nonetheless, the Jeepster is ready for many more miles Long live the AMC I-6.

 

[jimchere]

Re: Better way to drill out snapped bolts?

OMC, thanks, I lubed the bit with dabbles of used motor oil that I hadn't yet got around to dropping off for recycling, for what its worth.

 

[Skinnywater]

Re: Better way to drill out snapped bolts?

For future reference, I have a set of right hand cobalt drill bits and twist extractors. <br />It's a set of six bits and corresponding extractors. I bought them pretty reasonably from the MAC tool truck years ago.<br />The idea is that the right hand bit may grab the broken bolt and extract it while your drilling. In reality it does just that quite often. <br />I sure like cobalt bits and my Drill Doctor.<br />Nothing works better the just plain patience when extracting broken bolts though.

 

[jimchere]

Re: Better way to drill out snapped bolts?

Yea Skinny, those cobalt bits are worth the price. I'd a snapped probably a dozen cheaper bits in the process. I forgot to mention this to anyone else doing something similar: A GOOD set of safety goggles..

 

[ndemge]

Re: Better way to drill out snapped bolts?

weld a nut to it

 

[RPJS]

Re: Better way to drill out snapped bolts?

When putting the new bolts in give them a good coat of "Copper Slip" it will save you the same problem at 200K