Rusty Bolt extraction, Fast help please.
Melting Slicks
Joined: Oct 2002
Posts: 2,865
Likes: 1
From: I may be getting old but I refuse to grow up
I have always heard that Kroil is the best penetrant but I have never seen it in any of the common auto parts stores. I have used PB Blaster successfully many times but you have to be a little patient. Spray the bolt before you leave for work, spray it again when you get home. Repeat for a few days. Clamp your Vice Grips on the bolt and try to get it to move a tiny bit. Once the bolt moves even a hair you know you are going to win. Keep wiggling the bolt back and forth without applying too much pressure and keep spraying the PB Blaster. The bolt will gradually move more and more until you can thread it out.
I have drilled out bolts successfully also but I only do that when I can't get a vice grip on the broken piece. It's very difficult to get a drill bit in the center of an uneven surface and if the bolt is a grade 8 it takes a long time to drill it out.
Rick B.
I have drilled out bolts successfully also but I only do that when I can't get a vice grip on the broken piece. It's very difficult to get a drill bit in the center of an uneven surface and if the bolt is a grade 8 it takes a long time to drill it out.
Rick B.
Racer
Joined: Mar 2011
Posts: 252
Likes: 3
Thread Starter
Drifting
Joined: Jun 2008
Posts: 1,495
Likes: 134
From: Blanco County, TX
These are some great ideas. Thanks.
Unfortunately, no MIG. But I really like that idea. This is the third or fouth time a MIG would come in handy. I might just buy one and practice with it....even though just buying a new bumper piece would be cheaper.
I'll try the wax, but the nut is completely inaccessible so I can only heat the bolt and the backside of the metal that the bolt is welded to. I can't get to or see the nut. I only have a benzene soldering torch, which has helped in the past.
I gave the vise grips another try. It's a Craftsman and clean, but the teeth aren't perfect. No go on that so far and it took all my strength to clamp it on. But no wax yet.
I think I'll try the wax trick and the bolt extractor next.
In the end, I think I will probably end up twisting the bumper. No good way to hold it without damaging it. I've got it in the vise closer to the bolt than is shown in the picture.
I'll let you know how it turns out.
Thanks again.
Unfortunately, no MIG. But I really like that idea. This is the third or fouth time a MIG would come in handy. I might just buy one and practice with it....even though just buying a new bumper piece would be cheaper.
I'll try the wax, but the nut is completely inaccessible so I can only heat the bolt and the backside of the metal that the bolt is welded to. I can't get to or see the nut. I only have a benzene soldering torch, which has helped in the past.
I gave the vise grips another try. It's a Craftsman and clean, but the teeth aren't perfect. No go on that so far and it took all my strength to clamp it on. But no wax yet.
I think I'll try the wax trick and the bolt extractor next.
In the end, I think I will probably end up twisting the bumper. No good way to hold it without damaging it. I've got it in the vise closer to the bolt than is shown in the picture.
I'll let you know how it turns out.
Thanks again.
Thread Starter
Drifting
Joined: Jun 2008
Posts: 1,495
Likes: 134
From: Blanco County, TX
Ok, Tried the heat and the wax. Enough heat to start a small fire. Use a pipe wrench to grab it. The pipe wrench bit into it good. Unfortunately, I egged the drilled hole. Got a new bite and it started to turn....only I just lost 1/4" of bolt.... twisted it off.
Patience grasshopper... the agony of defeat. I'll try the bolt extractor next....and I blued the chrome a bit...not that anybody can see that part
Patience grasshopper... the agony of defeat. I'll try the bolt extractor next....and I blued the chrome a bit...not that anybody can see that part
Melting Slicks
Joined: Mar 2007
Posts: 2,520
Likes: 11
From: Hinckley OH
I doubt that those bolt extractors come in a small enough size. They are made to remove bolts with rounded off heads and they work well for that.
If money isn't an issue I would recommend getting that mig welder. You will probably need it again. The other thing you might try is to take it to a welding shop and have them weld a nut onto what's left of the bolt and ask them to unscrew it while it is still hot. I would take the smallest nut that will fit over what's left of the bolt and a ratchet and socket to fit with me so you know they have the right tools. It's such a small job that it can't cost much and they might even do it for free.
If money isn't an issue I would recommend getting that mig welder. You will probably need it again. The other thing you might try is to take it to a welding shop and have them weld a nut onto what's left of the bolt and ask them to unscrew it while it is still hot. I would take the smallest nut that will fit over what's left of the bolt and a ratchet and socket to fit with me so you know they have the right tools. It's such a small job that it can't cost much and they might even do it for free.
Racer
Joined: Jul 2004
Posts: 441
Likes: 1
From: Windsor Ontario
See if you can cut, or grind the bolt until its flat and almost flush. Next put a very small center punch mark in the center of the bolt. If it looks centred make it bigger, if off center move it over until its center the make it deeper. Use a small drill and drill through, keep going bigger with the drills until you are as big as you can without hitting threads. Then use a very fine pointed punch to collapse the remaining threads enough to grab with needle nose pliers.
I use this method as a very last resort
I use this method as a very last resort
Last edited by toolman0114; Feb 26, 2013 at 10:50 AM.
Melting Slicks
Joined: Oct 2003
Posts: 2,141
Likes: 804
From: Chapel Hill NC
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PB blaster has never failed me but sometimes it would take a week of daily soaking.
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Le Mans Master
Joined: Jul 2006
Posts: 8,117
Likes: 104
From: charlotte north carolina
cut off the end of the bolt and retry your original technique of drilling and retapping. if you don't feel confident, take it to a machine shop and let them tackle it. don't use heat or try to weld it(imo), you'll just ruin the chrome. main objective here is-don't cause more damage.
Racer
Joined: Aug 2009
Posts: 360
Likes: 69
From: Somers New York
See if you ca cut, or gringo the bolt until its flat and almost flush. Next put a very small center punch mark in the center of the bolt. If it looks centred make it bigger, if off center move it over until its center the make it deeper. Use a small drill and drill through, keep going bigger with the drills until you are as big as you can without hitting threads. Then use a very fine pointed punch to collapse the remaining threads enough to grab with needle nose pliers.
I use this method as a very last resort
I use this method as a very last resort
I used this method to replace all of the broken off exhaust manifold studs on a Cat D6 dozer. If you go this route, go to WW Grainger or another industrial supply company and buy a super premium set of drill bits. You'll be glad you did. If it's a blind hole you'll also need a bottoming tap.
Thread Starter
Drifting
Joined: Jun 2008
Posts: 1,495
Likes: 134
From: Blanco County, TX
See if you ca cut, or gringo the bolt until its flat and almost flush. Next put a very small center punch mark in the center of the bolt. If it looks centred make it bigger, if off center move it over until its center the make it deeper. Use a small drill and drill through, keep going bigger with the drills until you are as big as you can without hitting threads. Then use a very fine pointed punch to collapse the remaining threads enough to grab with needle nose pliers.
I use this method as a very last resort
I use this method as a very last resort
I wish I had used the pipe wrench before I drilled for the EZ out. I got a solid bite with it and could apply plenty of torque, much better than vise grips. In the meantime, twice daily PB Blaster soakings until I get the bolt extractor (assuming I can find one small enough). If that fails or I twist it off again, your suggestion will be the final and only option.
Racer
Joined: Jul 2004
Posts: 441
Likes: 1
From: Windsor Ontario
Once you drill the hole to the point where you can't go bigger without hitting the threads, use a small pointed punch to roll, or collapse the threads towards the center of the hole. When you do this you will be able to grab the collapsed threads with small needle nose pliers and undo it.
I am a toolmaker/machine repairman with 35 years in the trade.
I am a toolmaker/machine repairman with 35 years in the trade.
Thread Starter
Drifting
Joined: Jun 2008
Posts: 1,495
Likes: 134
From: Blanco County, TX
Once you drill the hole to the point where you can't go bigger without hitting the threads, use a small pointed punch to roll, or collapse the threads towards the center of the hole. When you do this you will be able to grab the collapsed threads with small needle nose pliers and undo it.
I understand I can get the threads out. It is the rest of the bolt that is threaded past the nut that I can't get out. There is a completely enclosed pocket in the bumper. Sorry, If I didn't explain that clearly. Or am I missing something?
I, unfortunately, am not. I do have a drill press, but I'm not sure I can get the bumper lined up on it.
Last edited by Kevin68; Feb 26, 2013 at 12:25 PM.
Former Vendor
Joined: Feb 2005
Posts: 609
Likes: 1
There is not a bolt inside the bumperette. There is a nut, spot welded to the bracket. Care must be taken in man handling the broken stub because you can break loose the nut giving you a mess to fix. Heat and the candle work well when you can get the nut hot. The problem is the nut is surronded by the bracket and you cannot get to the nut. Either drill it out and tap it or go back to heat and try to get the nut hot. If all fails we have rechromed GM Bumperettes for $90/ea with no broken bolts.
Best of luck
Best of luck
Thread Starter
Drifting
Joined: Jun 2008
Posts: 1,495
Likes: 134
From: Blanco County, TX
Anybody have luck with one of these? It was more than the Craftsman bolt extractor, so I'm assuming it isn't a complete POS.
Le Mans Master
Joined: Jul 2006
Posts: 8,117
Likes: 104
From: charlotte north carolina
people are afraid to drill out bolts because they use the wrong drills, and think that it takes hours to do. do it right and it won't take 30 minutes. you keep messing with those bolt extactors and you're going to break off the welded nut-then you're in deep do-do. go back to your original technique. flatten the end of the broken bolt(with a saw or grinding wheel) and mark the center with a point or a dremel tool. if you miss the center, go back and try again. then drill an 1/8" hole through the bolt. throw out those crappy black and decker p.o.s. drills and get some rigid brand drills from home depot. use firm pressure, oil and low to medium speed. those drills will easily cut thru the bolt (unless someone used a grade 8). get some 'center cut' drills(machine shops use them) that have a non-cutting point that will follow your first hole and not drift off center, and you'll cut thru that bolt in no time.
you're making a big production out of this-do it the way a machine shop would! i've rebuilt thre of these rusty clunkers and have drilled out more bolts than i care to think about. do it the smart way. get that bumper back on the car where it belongs.
you're making a big production out of this-do it the way a machine shop would! i've rebuilt thre of these rusty clunkers and have drilled out more bolts than i care to think about. do it the smart way. get that bumper back on the car where it belongs.