Broken Bolt - Thermostat Housing to Intake Manifold

[Tynan918]

I've tried to drill it in with a left handed drill bit for an extractor bit to extract it but didn't have center punches to use in the beginning...tore the bolt up...

Can't get housing on without it leaking, of course.

How can I get this bolt out ?

 

[airboatgreg]

Center punch center of the bolt. Be very precise. Start with a small drill bit and work to a larger one. TAKE YOUR TIME. If you are lucky the bolt will move into the water jacket. If not, when you JUST TOUCH the threads you may be able to run a tap through. If not a helicoil. Patience grasshopper

 

[buick7332]

I've tried to drill it in with a left handed drill bit for an extractor bit to extract it but didn't have center punches to use in the beginning...tore the bolt up...
View attachment 193691

Can't get housing on without it leaking, of course.

How can I get this bolt out ?

I never heard of a left hand drill bit. In the picture it looks like the bolt is broken off a little below the flange. What I would do is use a dremel tool with a small grinding bit and carefully grind the top of the bolt flat. Be careful not to scuff the side's. Using the right size drill bit (test that it fits snug in your other hole) slowly and straight try to drill down just enough so the bit makes a nice center point in the hole. Switch to a pilot bit and drill through the bolt. Use tape on your drill bit so you don't go to deep. Switch back to the other bit and carefully drill out the rest. Now run a starter tap in the hole followed by a bottom tap. Don't be afraid, just go slow,steady, and straight. If you screw the hole up you can always use a heli coil repair kit. Good luck

 

[08Malibu]

I never heard of a left hand drill bit. In the picture it looks like the bolt is broken off a little below the flange. What I would do is use a dremel tool with a small grinding bit and carefully grind the top of the bolt flat. Be careful not to scuff the side's. Using the right size drill bit (test that it fits snug in your other hole) slowly and straight try to drill down just enough so the bit makes a nice center point in the hole. Switch to a pilot bit and drill through the bolt. Use tape on your drill bit so you don't go to deep. Switch back to the other bit and carefully drill out the rest. Now run a starter tap in the hole followed by a bottom tap. Don't be afraid, just go slow,steady, and straight. If you screw the hole up you can always use a heli coil repair kit. Good luck

never heard of a left hand drill bit? They come in kits with ez outs.

 

[565bbchevy]

I never heard of a left hand drill bit.

I discovered the left hand drill bits decades ago trying to extract a broken distributor bolt from an aluminum intake, the right hand drill bit I used initially would catch and force the broken piece deeper in the intake since they spin in the same direction.
Obviously, you need to run the drill in reverse for it to work correctly.

 

[83MonteCarloSS]

The next time that happens to me I am going to try to use a mig welder to weld a nut on top of it. It will heat it up as well which might help with extraction.

 

[565bbchevy]

The next time that happens to me I am going to try to use a mig welder to weld a nut on top of it. It will heat it up as well which might help with extraction.

That method does work but you need the break to be above the hole.

 

[83MonteCarloSS]

That method does work but you need the break to be above the hole.

What if you stack some welds on top of the broken bolt and then weld down through the nut onto the welded material added to the broken piece?

 

[565bbchevy]

What if you stack some welds on top of the broken bolt and then weld down through the nut onto the welded material added to the broken piece?

I think that would possibly work as long as they are dissimilar metals and depending how deep in the hole the break is.

 

[Bonnewagon]

Left handed drill bits are true lifesavers. The center punch is key so it gets started correctly. But hell, even a big-azz nail will work as a punch. Just grind the tip as sharp as you can.