So I just wanted to flush my cooling system and replace the thermostat. The trucks been overheating in stop and go traffic. I figured I'd start with the cheapest/easiest first. Well when I took off the thermostat housing one of the bolts broke off. I thought no big deal I’ll just drill a hole and use an easy out. Well the easy out broke off in the hole and I can’t drill it out. I spent hours trying and broke all my drill bits that would fit. Is there any way to replace the lower part of the housing with out replacing the whole efi manifold?

 

I would do anything I can to get the piece of easy-out out and then drill it to the tap size and re-tap it. Use a punch and beat on the easy out and break all the pieces out of it. If you get out the hardened part, you will be able to drill out the old bolt and re-tap the hole. Other option would be if you can get the housing out you could also take it to a machine shop and have them mill it out and re-tap the hole.

 

I tried drilling for a long time. A machine shop would be able to get it out i'm sure but for now I just put it back with the one bolt and some gaskett maker around the broken bolt. It's holding well for now but if it doesn't keep holding I'm gonna head to a junk yard and get a intake manifold and replace it.

 

The intake manifold is two pieces, the upper manifold and lower manifold. You would need the lower manifold to fix your problen.

 

I had the same thing happen to me when I was changing my thermostat. It's EXTREMELY frustrating to say the least. Yotard was right about breaking the easy out with a punch. I carefully drilled another hole beside the broken easy out (partially in the aluminum) and used a small, sharp punch to chip pieces out with. Then I drilled and tapped the hole again. Good luck with yours whichever way you decide to fix it.

 

Uh, don't be so sure. The first thing they are going to ask (because they see it all the time), "did you break a screw extractor in there?" Their drill bits aren't any harder than yours. If it was in something worth real money (a jet engine...) they'd have to use an EDM tool to erode out the easy-out.

You may get lucky as one poster did and be able to drill "around" the easy out to break it out. But I would give serious consideration to getting a replacement manifold.

 

I have not tired this method, but I have heard that it can sometimes work to remove a broken easy-out (probably an extreme long shot).

Using a metal engraver try to push on the broken easy out to rotate it clockwise, the vibration from the tool may help to loosen it.

Again, this is a long shot, but metal engravers are cheap and it shouldn't hurt anything.

 

Also, why doesn't someone create an easy out that has an area that will shear off outside of the bolt hole so you can get a wrench on the broken shaft and back it out?

 

Use a Dremel with a thin cut-off disk to grind a slot in the top of the broken bolt. Then get a nice sharp flat screwdriver that fits PERFECTLY into the slot and remove it like flat screw. PB Blaster and heat around the aluminum are good ideas too.

 

Ignore the shiny new bolt on the right. The one on the left is off an old Honda motorcycle from when they used Phillips screws to hold the cases together. After 30 years they are pretty much impossile to remove without damaging them. Even with an impact driver. Once I slot them with a Dremel they come out fairly easily with a flat screwdriver.

 

Also, valve grinding compound on the tip of the screwdriver keeps the driver from slipping on the head of the screw. Works great when rebuilding old motorcycle carbs with tiny little screws.

 

Granted it wrecks a CARBIDE end mill so don't use a brand new one, but it works just fine. I don't have an EDM in my shop and I have saved plenty of people's mistakes from broken taps and easy outs.