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Tricks for removing stuck bolts and nuts

I’m just a Saturday mechanic with a Sears Craftman ratchet set and a few screwdrivers is about all I have, but I’ve come across plenty of stuck bolts and nuts and other parts rusted stuck. One of the most memorable was a front brake disc. The disc in normal operation is held to the wheel by the tire and the wheel lugs , so the disk is just held on to the backing plate by a phillips screw so it doesn’t drop off when you take the tire off when doing service. Well, I removed the brake caliper then the phillips screw but the disc wouldn’t budge. And it wouldn’t come off no matter what I did. I applied heat. Lot’s of heat. It wouldn’t budge. I crawled under the car wearing short pants – this part is important to the story! – anyway I’m laying on my back pounding my fist on the disc from the underside of the car to knock it off, no go, so I take a break for a minute to catch my breath, just laying there wheezing. I guess in the meantime the heat got distributed to where it was supposed to go in the first place, and all of a sudden without me doing anything and with no warming it just fell off. And landed on my bare leg. Hotter than hades! Ouch! lol … well, it wasn’t funny then, but it’s funny now.

Anyway, what are your secrets to remove stuck parts? Here’s mine

  • Penetrating oil and time
  • Heat
  • Nut splitter (a small gadget to split open stuck on nuts so you just pry them off)
  • Manual Impact driver (a small gadget, you knock it with a hammer and it twists slightly, to remove stuck screws and bolts)
  • And the biggest secret: If I need more room to work, I take more stuff off to get better access.

What are your other secrets for removing stuck parts? Any funny stories?

I don’t think actual mechanics can afford to spend time with stubborn stuck bolts. What do they use? Air impact wrenches?

PB Blaster , is one lazyman option, a blow torch number 2, cutting wheel or oxy acetylene torch #3

Edit impact wrench first then above!

If there is enough room and enough bolt or nut to grab, I have an 18" pipe wrench that works well. This is usually after a PB Blaster soaking. I recently used a manual impact driver to replace the door latch on my Explorer. It wasn’t rusted, but was tight enough where a simple screwdriver couldn’t loosen the phillips head screws. A power driver would have most likely damaged the screw heads. Used it to tighten the screws again on re-install.

Wrestling stuck fasteners is a way of life for mechanics and time has to be spent on that pain in the neck job no matter how proficient the mechanic. Other than what you’ve mentioned, welding a nut onto a broken bolt is an option and in some cases if there’s enough of a nub still protruding a tiny monkey wrench can work them loose.
I avoided mentioning E-Z Outs because while they may work if one is careful, and lucky, there’s also a strong possibiilty of an E-Z Out breaking off in the fastener and then it becomes a double headache.

In some cases there is no option but to drill the bolt out and retap the threads or install a thread insert.

The oxy acetylene torch succeeds when all else fails…

An acetylene torch is hard to beat. I sometimes press a candle at the base of the threads after heating and move the bolt back and forth to get the wax to wick down and lubricate the joint. Stuck parts seem to be the coup de grace for would be mechanics. After needing to be bailed out a few times after breaking bolts they just give up on trying.

Tell me about stuck/rusted fasteners. Here’s what had to be done in order to remove the long bolts from the knuckles in order to replace the rear lateral links on a Camry. And it took a day of heating up and cooling down with an oxy/acetylene outfit before they broke loose.

Tester

I don’t do much of heavy work, but have an assortment of schedule 40 PVC pipe and keep adding length and girth to the wrench until something happens.

Since it got me more than once, I’ll add this: Make sure your “stuck bolt” isn’t actually just reverse-threaded.

I doubt I have anything special to add, though once I bought an air impact I couldn’t figure out why I’d waited so long to do it. Its not that it does everything, but it works wonders on many things I used to wrestle with. Impact of some kind is always my favorite approach. If I can’t fit the air tool I find a way to at least whack the wrench or socket with a heavy hammer - poor man’s impact.

Along with that goes the PB Blaster and, of course, heating. I’ve recently added cooling to that. So I’ll heat it up a whole lot. Then I turn one of those compressed air cans upside down and blast with that that. A couple cycles of that with some PB Blaster loosened up a broken head bolt for me quite nicely when I needed it to. After a bit of that the rest of the bolt came out with a pair of channel lock pliers. I’ve also done other normal things like pounded the next smaller size socket onto a bolt head (I prefer 12pts for that) or cut a slot in a stripped phillips head to get a grab with a flat blade…stuff like that.

My only real “failure” so far was an axle nut. I broke a 1/2" breaker bar on it while jumping up and down on an added 4 or 5ft cheater pipe. I finally put the tire back on and drove it to a shop I use. I asked them to break it loose & snug it back up so I could drive it home. My shade tree air tools are handy - but no match for the professional shop.

Tester - you need to move out of Minnesota or wherever it is. No one should have to deal with that much rust on a regular basis. Arizona’s much nicer on mechanics I’ll bet.

You get used to it.

Tester

For really stuck fasteners, the old oxyacetylene torch beats all. I have used this particular tool to get stuff loose that people said could not be taken loose, mostly exhaust manifold studs and what not. I have dealt with studs people have broken off nearly flush on the flange. If I can get a pair of Vise Grips on it and put a torch to it, I can get it out of there. Just get it glowing bright red-orange, like it’s darn near ready to melt, and spin it out.

For rounded off Torx or Allen bolts, just take a cutoff wheel to the head of the bolt and cut a notch in the center of it, then use a nice fat flathead screwdriver to remove the offending bolt. This also works with bolts that have broken off at the head due to pressure or vibration, but not usually due to being seized or cross-threaded. I work in a factory and use this trick on the machines all the time, as vibration causes a lot of broken fasteners on those machines.

I like my I-R 231 C impact wrench. When something is rusted, I’ll soak it with PB Blaster. The trick I’ve found for brake rotors rusted to the hub? Hit the disc on the edge radially, swinging the hammer toward the center. Do this repeatedly while turning the disc so you get around the whole circumference, or 'till it breaks loose. An air chisel with a flat riveting bit works REAL quick on these.

For those shops that can afford the luxury:

http://www.theinductor.com/

I also use an impact wrench. It will often loosen frozen nuts and bolts where brute force applied will otherwise break the threaded shaft.

Increasingly heavy application of hammer blows on a cold chisel applied to the edges of pan head bolts as commonly used on motorcycle engines will loosen the bolt if the Allen pattern slot in the bolt head has been ruined. This technique can be used elsewhere, even on hex head nuts and bolts when there is room to do so.

A Vise-Grip type tool is good to use in some situations.

As stated, nothing beats the fire wrench. I have yet to have been foiled when the fastener is heated orange-red. They come out, kicking and squealing but they come out. Many people have this perception that you can’t work in tight spaces with the torch but I think many people would be surprised what you can do with it. Heating and cutting in confined spaces takes a lot of practice but that’s where chopping up beaters before junking them helps to refine that skill.

A sawzall is sometimes needed. As one example, I cut brake disks off several times when nothing else seemed to work. And it’s amazingly quick with the right blade. It’s often far cheaper in the end and less frustrating to cut something off and replace than to wrestle with and try to save something that’s rusted enough to not come out using normal force.

Pipe wrenches work far better than any other binding/biting wrench. The only wrench I know of that gets tighter the harder you push on it.

Air power is almost always better then simple mechanical leverage. Hammering force coupled with compact size means you can get into small spaces with great advantage. Pneumatic wrenches, air hammers/chisels, drills etc are way more powerful for their size than electric.

I have a few tools in non-human proportions that are indispensible; a monsterous slip joint pliers, pipe wrench and pry bar.

I’ve used just about every penetrating oil and my preference hands down is B’Laster PB.

A whole bunch of great comments. Thanks. I’ve never heard of using wax, I’ll try that idea. And using both heating and cooling seems better than just heating. I’ll try that. I have a dremmel tool, and sometimes use the cut-off wheel to cut stuck parts off sometimes. I tend to use that more for plumbing than cars though. I forgot about that in my OP list. It appears the air-powered impact-drive ratchet is the tool that separates the amateurs from the pros. This weekend I’ll pop over to Harbor Freight and see what they have there. I already have a compressor, but I’ve only used it for pumping up tires and for spraying paint. Since it appears the air impact wrench is the way to go, I’ll be getting one, and use it w/my compressor. I may have to wait until I find one at a flea market though, being a little cash-poor, I may need to find a bargain used.

A couple of questions:

I don’t see myself getting an oxy-acytelene torch. I think I’d burn my garage down if I had one of those. I’m not so mechanically inclined enough to trust myself with oxy-acetyline, as you can probably see from my posts! I have used a propane torch for applying heat though. I’ve noticed on the tool-store shelves what appear to be disposable torches at a fairly modest price for something like 15 minutes of use that use something different from propane for the fuel. Anybody used those? How do they compare to propane? Hotter? Not as hot? They seem like they are very compact and might fit into a tight spot, where a propane torch wouldn’t. They might well come in very handy, if they worked well.

About penetrating oil … I’ve used a product called ‘Liquid Wrench’ for my penetrating oil. I notice most folks here use something called “PB Blaster”. Is PB Blaster better than Liquid Wrench? How so?

I will add that if you’re dealing with a stuck fastener it’s not always a good idea to try and just winch the thing loose in one shot. Seesaw the wrench or socket as the case may be back and forth in both loosening and tightening directions. If it does break loose continue to seesaw it a bit as you remove it until you’re sure that it’s fully loosened. The same thing applies when using an air wrench. Yo-yo it a bit back and forth.

There’s barely any difference heat-wise between butane and propane so I’d just continue using what you have with access being the main factor.

Just my opinion, but there’s also very little difference between Liquid Wrench and PB Blaster. Both work well.
If you want to mix your own homebrew penetrant you can use a squirt bottle and fill it with a mix of 50% kerosene, 35% mineral spirits, and 15% alcohol. This is generally not worth the hassle unless you deal with rusted fasteners on a pretty regular basis though. Hope that helps.

If you need more heat than propane has to offer, try MAPP gas. I don’t have the bucks to own an oxyacetylene setup, so MAPP is what I usually resort to. It’s definitely hotter than propane, but does cost more. The heat difference is worth the price difference.

OK4450 … here’s a funny story you reminded me of. My next-door neighbor friend comes over one day, mad about something. I’m thinking he’s really mad about something I’ve done, I wonder what it was this time, last time I left the garbage cans out on the street too long after pickup. But luckily this time he’s mad at his plumber, not me. I say “what did the plumber do?”. He says he had the plumber come over to fix the kitchen faucet. The plumber decided he had to take the faucet off and work on it on the bench in his plumbing truck. But he has trouble getting the top-side faucet nuts to come loose. So he walks in on the plumber working there in the kitchen just as he’s twisting the nuts in the tightening direction. My neighbor, he goes bezerk! “How can you be a plumber when you don’t even know which direction is loose!”. He sent the plumber packing! And the kitchen faucet remains broken.

So he’s complaining to me about this, that he needs to find a new plumber, when I tell him “Oh, you know what? I think the plumber probably knew what he was doing. After all he does it all the time. Plumbers sometimes loosen stuck nuts by tightening them first.” I never asked what happened next. This is something I’ve learned. It’s best not to ask anyone about their plumbing problem. …lol …