emaster Posted May 26, 2009 Share Posted May 26, 2009 hey guys, I broke an exhaust manifold bolt inside the engine block... what do I have to do to get it out? Quote Link to comment Share on other sites More sharing options...
Jehannum Posted May 26, 2009 Share Posted May 26, 2009 Stop trying to bolt your exhaust manifold to the block. It attaches to the head. Also: take it to a machine shop, they'll be able to get it out no problem. Quote Link to comment Share on other sites More sharing options...
FlatBlack Posted May 27, 2009 Share Posted May 27, 2009 We just had an entire thread about getting stuck head bolts out of the block. Go buy these: They're called bolt extractors. Shouldn't be difficult, just drill into the broken off stud and extract. Jehannum, Come on, is this a Vee Dub Forum?? ["Take it to a machine shop"] Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted May 27, 2009 Share Posted May 27, 2009 NAPA auto parts will drill the bolt out for $25 or laser it out for $60 Quote Link to comment Share on other sites More sharing options...
Oddmanout84 Posted May 27, 2009 Share Posted May 27, 2009 Maybe its my method, but I've snapped a few bolt extractors in the bolts I was trying to remove!! They can be frustrating! Quote Link to comment Share on other sites More sharing options...
Jehannum Posted May 27, 2009 Share Posted May 27, 2009 We just had an entire thread about getting stuck head bolts out of the block. Go buy these: They're called bolt extractors. Shouldn't be difficult, just drill into the broken off stud and extract. Jehannum, Come on, is this a Vee Dub Forum?? ["Take it to a machine shop"] I'll defer to the old wisdom: an E-Z out is a tool that snaps off in bolt holes and is ten times harder than any known drill bit. If it's snapped off below the surface of the head, I'd take it to a shop. If it's broken off above, I'd consider welding a nut on before taking that (now bigger) mess to the shop. Quote Link to comment Share on other sites More sharing options...
emaster Posted May 27, 2009 Author Share Posted May 27, 2009 I am trying to use a screw extractor, So far it is slipping inside the bolt. I think I need a bigger one. I have a ton of screw extractors, in fact I have the EXACT same set as shown in the picture, the problem is, is that one is made of a metal way too soft and the threads of it bend. I will show pics after im done with school today. I never thought of welding something to the bolt and then spinning that... but thats a last resort. Putting my header on wasn't supposed to be this much work Quote Link to comment Share on other sites More sharing options...
Oddmanout84 Posted May 27, 2009 Share Posted May 27, 2009 I am trying to use a screw extractor, So far it is slipping inside the bolt. I think I need a bigger one. I have a ton of screw extractors, in fact I have the EXACT same set as shown in the picture, the problem is, is that one is made of a metal way too soft and the threads of it bend. I will show pics after im done with school today. I never thought of welding something to the bolt and then spinning that... but thats a last resort. Putting my header on wasn't supposed to be this much work Don't worry, I went through the same process with my headers. Lemme guess, its one of the studs at the very front or rear of the head? Mine snapped too. Lol, I've been driving my car for a few months and its still not fixed. Not the best thing, I know, but the other bolts hold the headers on just fine. Quote Link to comment Share on other sites More sharing options...
FlatBlack Posted May 27, 2009 Share Posted May 27, 2009 The furthest bolt [exhuast] towards the radiator and the furthest bolt towards the firewall both were broken off inside my P79. I ended up heli-coiling the head and it hasn't leaked at all. Quote Link to comment Share on other sites More sharing options...
Oddmanout84 Posted May 27, 2009 Share Posted May 27, 2009 The furthest bolt [exhuast] towards the radiator and the furthest bolt towards the firewall both were broken off inside my P79. I ended up heli-coiling the head and it hasn't leaked at all. ... which is what I should be doing, but I've been lazy. I might as well wait till I do the engine swap though. Quote Link to comment Share on other sites More sharing options...
FlatBlack Posted May 27, 2009 Share Posted May 27, 2009 Yeah I did it when I put a new head gasket on [with ARP Head studs]. Quote Link to comment Share on other sites More sharing options...
Jeff260z Posted May 28, 2009 Share Posted May 28, 2009 There are two kinds of broken bolts. One you break from over tightening (or stressing) the other you break trying to remove. The first one is always easiest the get out as the broken piece is usually not seized into the hole. The second scenario is usually a big pain to remove. Imagine why it broke in the first place. The threads are seized and the stud or bolt broke rather than get them free. Bolt extractors will rarely work by themselves here. You had a complete bolt to begin with and it broke now you are going to try removing the broken section with an extractor hmm. If broken in the block you can use heat from a torch (propane should do) to get the corrosion to break free between the bolt and block. Then try the extractor. Most will come out with heat. Do not worry to much about warping or damaging the block. Heat the stud or bolt. It will expand faster than the metal in the block as the rust insulates it. I've done this many times. Quote Link to comment Share on other sites More sharing options...
emaster Posted May 28, 2009 Author Share Posted May 28, 2009 Yeah well I broke the screw extractor inside the bolt... I am going to take a hammer with a punch to it to shatter the screw extractor, if that doesn't work I will use an air chisel with a punch attachment to break the screw extractor. After that is gone then jolts from that should break the rust and stuff around the bolt loose and I can someone else who is better at this help me out with the screw extractor. If we cant get it out we can just then drill it out with the right size drill bit and use a tap for the threads... Sound good? Quote Link to comment Share on other sites More sharing options...
Oddmanout84 Posted May 28, 2009 Share Posted May 28, 2009 Careful, since you are still working around aluminum! Most auto stores also sell a spray that freezes bolts, so maybe you could use that to shock the rust along with light use of a torch if you're careful. Quote Link to comment Share on other sites More sharing options...
Nuke Posted May 31, 2009 Share Posted May 31, 2009 I had 3 head bolts break because they were corroded to the thread from general conditions near an engine. They also had corrosion near the head, attaching them pretty firmly to the head. With lots of hammering, penetrating oil, a torch, and some wax, the head was broken (not literally) free and removed. All 3 bolts were broken above the thread by a fair amount, one broke free with a vice grip and more heat and hammering very easily. The other two were near impossible to remove. They ended up breaking again flush with the block. With quiet contemplation, we decided to use a magnetic drill press to remove said bolts, starting small and moving up, then using a tap to clean out the remaining metal. It was not pretty at first, and a little scary with a drill on the block, but it can be done. I would suggest doing this as a LAST resort. Broken bolt removers of all sorts did not work and ended as a waste of money in all cases on these bolts also. These three small pieces of metal turned a valve job into a complete nightmare! Quote Link to comment Share on other sites More sharing options...
blue72 Posted May 31, 2009 Share Posted May 31, 2009 Yes, be very careful around the aluminum. I've removed the remains of a broken exhaust bolt from a P79 head before. The drill has to be exactly centered and it would be best to work up to the final size. I went very carefully with a battery powered hand drill and eventually worked the appropriately sized tap down through the hole removing the last of the thread pieces. If you don't get it right, then it'll be time for the helicoil. I've got one broken in an N42 that I'm going to be removing with a drill press next. I've also removed broken head bolts from a block by quickly welding on a nut to the bit that extended above the surface of the block. The combination of heat and the torque from a wrench did the trick, just as long as the weld was solid. Quote Link to comment Share on other sites More sharing options...
240Zed Posted May 31, 2009 Share Posted May 31, 2009 I drill a hole in the end of the bolt and hammer an appropriate sized, cut off Allen key into it. Then get a wrench onto it. Quote Link to comment Share on other sites More sharing options...
280zx 2by2 Posted May 31, 2009 Share Posted May 31, 2009 my $0.02 after having an extractor brake off into my head (insert an emoticon that expresses INTENSE frustration) i say drill it out (i cant remember the drill bit size) re tap it with a 10x1.25 tap and put a 10mm x1.25 stud in that mofo, i did this after one of my new 8mm studs broke not a week after i finished installing everything... if another breaks im converting to all 10mm bolts for my intake exhaust(the 4 intake bolts are already 10mm) if you want to go this direction ill go out and see if i can find that drill bit and get you the size but i will always try using extractors first (by hand not with a drill dohh!) because its a beautiful sight to see that broken stud make its way out Quote Link to comment Share on other sites More sharing options...
280zx 2by2 Posted May 31, 2009 Share Posted May 31, 2009 and about your issue of the extractor still in the hole, when i drilled out my 10mm hole the extractor came lose and i was able to vacuum it out btw vacum works good for keeping the metal shaving from finding their way into the clyinder head Quote Link to comment Share on other sites More sharing options...
zedsn Posted June 3, 2009 Share Posted June 3, 2009 I second the drill out the hole and retap. That is what I did. I used an existing bolt and slid it through a drill bit chart and selected a drill bit that was 2 sizes smaller and drilled the head and retaped it. I believe I tapped it with a SAE tap becasue I didn't have any metric taps at the time and wanted to get the job done. Just make sure that you drill the bolt in the center and not too deep! Quote Link to comment Share on other sites More sharing options...
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