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I need to remove a broken bolt in the oil cooler blockoff plate. There should be no tension on the bolt. I have a small extractor set. What methods would you recommend to remove this? Is it possible for me to get this out without having to remove the pan.
Here's a picture of the bolt and the bottom picture gives an idea of the depth inside the threads. I really, really don't want to have to remove the pan if it's not necessary.
If you do have to drill it use a left hand drill bit. If the bolt is not seized but just broken off from over torque lots of times the drill bit will back it out.
Weld some blobs right on top of the broken stud - the steel wire won't stick to the aluminum pan. Keep building up the blobs until you have some sticking up about 1/4" above the surface. Place a sacrificial nut over the blog and weld the nut to the blob tip. Congrats, you just make your very first bolt from scratch. Loosen while hot with a good 6 point socket.
Sometimes I get lucky with using an automatic center punch, the kind that you just push down and it pops pretty hard,
and get on a good bite at an angle where it would push it counterclockwise, then push it and let the pressure of the punch
spin it Good Luck.
I would first just try a pick to rotate it. I have had luck doing this several times. I just dig the pick into the broken piece near the thread root and tap it gently with a hammer to try and rotate the broken bolt. Hope that makes sense.
Thanks guys. I didn't get a chance to take a crack at it tonight. Hopefully tomorrow if the storms go away. I'll post and update on the results. Also, there was an exhaust manifold bolt broken off already in the block. I haven't searched the site yet, but I assume there's probably answers for the best way to remove that. I am assuming to first heat the area, and liberal use of PB Blaster, and heat some more, and then try to drill it and use an extractor first. If that's not successful, drill it and helicoil?
Like i said weld a nut to it and be done with it. The weld will not stick to the aluminum. The weld also gets the bolt hot and helps it come loose. I have removed more broken exhaust manifold bolts like this than i can count. If the first nut doesnt get it out, which they usually snap off if they dont. Weld another and try it again. Usually a stubborn one will take 2 or 3 tries. But ive never not removed one!!
If you are worried about melting the aluminum, tape a washer to the head and weld the hole up to it and tie the weld to the washer then set a nut on the washer and weld it. Works for me every time so far. Tip, if removing exhaust manifold bolts hit them with a hammer and punch first to break the dissimilar metal bond, also if you have one of the old hammer driven impact tools use that to get it going...
Good to know about all the heads being aluminum, I didn't realize that.
I do have the hammer driver impact style, however I couldn't quite understand what you were describing with welding the washer. Can you describe again what piece is going where when you tape the washer and weld it to which part?
THE MOST IMPORTANT thing to know first off is if it's cross threaded/rusted solid or not.
If it's not cross threaded use a pic to work it around and unscrew it out and put a new screw in it.
Left hand drill bits are your best friend in this scenario, as soon as the bit bites it unscrews the bolt right out
If it's cross threaded or rusted solid, center punch it drill it and use an ease out. Start with a tiny drill bit in case you're off center, then you can bring it more back center as you go up in bit size and you can also avoid drilling into the threads if you start small and aren't centered. Use the largest ease out you can so you have the most strength and hopefully don't snap off the ease out in the bolt.
On exhaust manifold bolts that break, they can be hard to get out but will come out if you're careful. But if you can weld a nut to what's left of it that works great too and you don't have to worry about drilling or breaking an ease out in the bolt.
Good to know about all the heads being aluminum, I didn't realize that.
I do have the hammer driver impact style, however I couldn't quite understand what you were describing with welding the washer. Can you describe again what piece is going where when you tape the washer and weld it to which part?
The reason I tape the washer is because it is damn hear impossible to hold the washer centered over the hole. It helps build up the bolt that is broken without damaging the aluminum head, ,plus it is easier to reach the bolt through the washer than through a nut. Now weld the nut to the washer and the broken bolt and un screw it. If you chose to use a E-zout get the square one that bites into the bolt, the spiral ones tend to expand the bolt and just make it tighter..
I was able to get the broken bolt in the oil pan out tonight. It came out pretty easy as I was able to get a bite on it with a chisel and lightly hammered it around. The head was a different story. I tried welding a nut to the end but I ended up having to drill it out. I posted the question in a new thread here: broken headbolt thread
The weld always worked for me. I turn the welder up and go at it. Dont be scared of messing the head up. The weld doesnt even hurt it. Ive gotten some bolts hot as **** welding to them without issues. Cherry red!!!
I buy 862 heads and rework them from a core yard and there is generally 2-3 broken exhaust bolts on them, the welded nut etc. has never failed to remove them. Glad you got it out.
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Remove broken bolt: oil cooler blockoff plate 
