Options for removing a recalcitrant broken bolt?

As described in another thread I had to replace the water pump in my engine. The impeller was a casualty of PO not changing the coolant after the car sat for 20 years. Well, to be honest partly my fault for not changing all the fluids first thing when I got it. I assumed because the PO had gone through the car to get it back together for sale he would have done this.

One of the bolts broke. No problem (I thought). I ran over to my dads and grabbed the easy outs. He suggested using the right angle drill attachment instead of pulling the radiator to drill the hold for the easy out.

I should have followed my gut and pulled the radiator anyways. I couldn't see what I was doing. I'm pretty sure the punch was centered when I punched the guide divot for the drill, but the drill apparently walked anyways. The drill didn't do any damage to the threads but the easy out.... did.

SO now I have a recessed broken bolt (still) and some threads that are messed up on one portion.

How the heck do I get the bolt backed out now? And what are my options regarding the threads? Can I chase the threads and leave it as is? The shop manual only calls for ~15ft-lb of torque.

sometimes a little heat will help break the bolt loose , is it a blind hole or is it the one that is open to the water jacket? If its broke off clean I would try to heat the area around it a little hoping the surrounding metal will expand faster than the bolt then either hit the area with candle wax or let it cool a little and spray it with PB Blaster and try to spin out with a small chisel. if that fails you may try a dremel with a carbide cutter and grind away at the bolt until it is thin enough to collapes the sides towards the middle. when you get it out you can make a determination on the thread condition. If the are too damaged just install a heli coil insert.

Another option in addition to/besides easyouts are left hand drill bits. In my experience they've worked better for me and Ive avoided munging up the threads as badly. Key is to start small and work up, trying to stay centered on the bolt. You might want to chase the threads with a tap after. You might not need a helicoil.

m.sears.com/productdetails.do?partNumber=00919883000P&sid=IDx01192011x000001

Best,
Perry

Thanks Perry. I saw a youtube entry describing just that last night. I'll give it a shot. I'm gonna spend the next couple of days blasting the hole with heat and penetrating oil first.

Hi 65fback.If the threads are as crapped up with corrosion as I think they are from the coolant,you might be better off turning the bolt remains to the right as if tightening it to screw it all the way into the coolant passage and then retrieving it with a magnet.BTDT.
Good luck.Have fun.Be safe.
Leo

After using every trick in the book, I still couldnt get the broken w/p bolt out and ended up pulling the engine and taking it to a machine shop to get the bolt removed and the threads repaired. (actually IIRC they had to put a thread insert in)

Is only one of the holes blind? This is my first foray into the block so I just don't know. The one I know is blind is free. The other free one is not blind.

So far I've had no luck with any of the suggestions. Its looking more and more like I'm going to have to pull the engine to get it out.

Got the bolt out last Saturday. Or more accurately, Gene 64 2 dr came over and got it out for me. Thanks Gene! The new water pump is going on this weekend. As soon as gaskets come in for the exhaust, head, valve cover and thermostat housing (I pulled it for better access to what I was doing with the water pump and to paint it) I should be back on the road.

Thanks for all the advice.

So what did Gene 64 do to get it out? Apply more experience to the problem?

Lots more experience. All I know how to do is apply heat and cuss at the stupid thing...

He was able to get a bit to bite close to the center without walking. After about an hour of heating/freezing, drilling and opening up a hole in the bolt we actually got an easy out to stay in and back the broken bolt out.

Dang. That's what friends are for.