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Thermostat housing bolt



When attempting to install a new thermostat and thermostat housing, I broke(twisted) off one of the 2 bolts that hold the housing in place. What is the best way to get this bolt out? Thanks for any advise.
Broken bolt removal

Go to any hardware or auto parts supply store and ask for a bolt extractor. tell them what size bolt you are extracting. The procedure is to drill out the center of the broken bolt and to screw in the extractor. The extractor is reverse threaded so you will have to turn it counterclockwise.
Be generous with a good penetrating oil before you try to get the bolt out. PB Blaster, or Kroil really work. If you can get a left hand drill bit this is also helpful as it turns to the loosening direction rather than tightening. Be careful not to twist off the extractor, happens a lot if you really try to force it.
Center punch the bolt as near the center as possible, if the easy out does not work you can drill the bolt out.Do not force the easy out or it will break and then its a mess. If you feel the easy out may break stop and drill the hole out to the tap drill size. Start with a smaller drill and then go bigger,when the hole is out to the tap drill size the threads may collapse enough to pull them out.Try to get the first couple threads out then run a tap in.Be careful with the tap also, so it does not break. If you mess the threads up you can go to a heli-coil.The main thing is you do not want to break an easy out or tap off. Chuck
Thanks for the info guys. You've been a big help. I picked up a 3/8 in. bolt extractor and new bolts at the hardware store and have the drills. I'm waiting until my new thermostat housing arrives before I attempt this....Thanks again..:)
When you get the new housing, take a sheet of glass and place some real super fine sand paper on it. (face-up.) Lightly rub the base of the new housing across the sand paper. This will tell you if the new housing is flat. Most are not and all chrome housing are warped from chroming them. Rub the base of the housing until it is flat.
Thanks Buckskin.....I would not have thought of that....Good idea..:w

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