How To Remove Rusted Screws, Nuts & Bolts In 10 Easy Steps
WD 40 Lubricant (or Diet Coke)
PB Blaster Penetrating Catalyst
If one of your hobbies is restoring classic cars, you WILL eventually learn one truth enemy, thy name is R U S T. What you thought was going to be a "simple project," can end up remaining "a work in progress" ...indefinitely...because a screw or bolt has rusted and become "one" with your car. Your "project" has now taken up lease in your garage...and refuses to pay rent. Your significant other is a broken record, asking in a loop, "when are you going to finish that "project!" Your fRUSTrated, tourettes-like outbursts do not help your project... OR your personal life. The only thing worse than a rusted bolt between you and success, is a snapped, rusted bolt...because you didn't know how to treat it properly before trying to loosen it...BIG MISTAKE. Resist the temptation to force something that shouldn't be forced. Breaking a blind stud can lead to hours of drilling out a busted shank.
We've all come across a nut that has rusted itself solid onto it's partnering bolt. Let's start with the two main reasons a screw, nut or bolt will not turn loose. One is that rust has formed between the threads and the part that it is threaded into. The other is that the screw or bolt was cross threaded when it was applied. At one time or another, everyone has come face to face with a stubborn (fill in the blank) that refuses to budge, no matter how much pressure your put on it. (I called mine my "husband") Believe me, it takes a LOT more than just muscle power to loosen these lovers without breaking them. The first thing you need to do is decide if the bolt is ready to break. (...or you are.) For example, exhaust manifold studs are notorious for corroding the thin shanks and breaking.
1. Using a small wire brush to clean the residue off the rust. If the metal is not corroded, then just use a dry cloth. Remove all rust from the root to the tip of the thread, so the nut doesn't seize suddenly when you turn it. Now ask yourself the following Is the bolt actually rusted or does it have locking compound (Many factory bolts have thread locker on them, and this can be softened with heat. If this is the case, see the "heat removal" section at the end of this article.) Is the bolt worth saving A rusted fastener won't have the clamping force to do its job. It may be easier to just break the bolt and replace it. Smaller fasteners (body bolts and screws) often can't be saved.
2. If you're determined to save your nut (...and I know I always am) spray it with WD 40 and tap the head of the bolt, screw or nut with a large tool. (WOW...it's getting harder and harder for me to keep a straight face.) This will allow the WD 40 to penetrate the grooves of the thread for more lubrication and better penetration. (My 8-12 year old Inner Child is SCREAMING to be let out right now.) Don't have any WD 40 on hand Try a Diet Coke. No...don't drink it...That stuff is chock full of acid! (Any cola will work, but DietCoke contains the most phosphoric acid, which is the active rust-eating ingredient.)
3. Let the bolt sit and soak. (Not nearly as much fun as "Sit N' Spin", which you might remember from childhood.) This can take only 5 minutes for quick fixes, up to several hours for hard jobs.
4. Selecting the proper tool will always make your life easier in the long run. (assuming that all "tools" are equal. wink) For instance, open-end wrenches are likely to round off the flats of a stuck nut, which is also why a 6-point box end is better than a 12-point one. A smaller nut gets a better fit with a smaller Metric or SAE size. IE. A ½ socket (12.7mm) may be a better fit on rusted 13mm nut.
A breaker bar or long handled ratchet will give more leverage. Always use steady, even pressure, paying close attention to the feel of each turn. (I think all your "body" work should be approached with this level of concentration.) If the tension suddenly becomes soft, (and, let's face it, this is NEVER a good thing) you are either breaking the bolt or stripping the threads. Wearing padded mechanics gloves will also cut back on the scraped knuckles. (...and the neighbors' pitiful looks toward your wife because of your uncontrollable tourettes.)
Carefully now, use your pliers to test the bolt and see if it works itself loose. NOTE Be sure you're turning it the correct way! I always remember the rhyme Lefty-Loosey, Righty-Tighty." Be careful not to get your spatial directions confused when working reversed or upside down. (Trying new positions is important though, so don't let me scare you away from them. smile) Exception Most threads loosen to the LEFT, but some ring gear bolts and old sixties Chrysler lug nuts are "backwards," and loosen to the RIGHT.
5. If it doesn't work itself loose, apply WD 40 again...this is not a "quickie"...this baby wants to cuddle all night. Build a cup to contain the WD 40 over the bolt or screw head. Window putty, or modeling clay works well to build a small cup around the bolt. Be generous with your putty, especially at the base, so the cup will not leak when lubricated. Fill the cup with WD 40 and let nature take it's course. After a few hours, check to see if the bolt can be moved. If the fastener still will not budge, use a rag to mop up WD 40 from the bowl, hit the bolt with a hammer to jolt the metal, then refill the putty cup with more WD 40. If she still won't budge by morning...you have a stage 4 "clinger" on your hands, and it's time to try "tough love."
6. You're going to have to spray the screw or nut with PB Blaster Penetrating Catalyst. (This sounds like more fun than it really is.) This is simply a penetrating oil designed to remove rust on screws, nuts & bolts that are stuck. When trying to remove a reluctant bolt, choose a quality socket wrench with as much leverage as space permits. Firmly place the wrench over the bolt, keeping the wrench as far down on the bolt head as you can. The goal is not to chew the bolt's head off. (...or nut off...you Get The Picture.) If the head of the bolt gets destroyed, then, you'll have to drill it out. (This too, sounds like much more fun than it is.) With persistence and proper lubrication, stubborn rust can be softened. Never re-use a rusty screw or nut when putting your "project" (or life) back together. Always start fresh, with a new screw or nut (or...whoever), and coat them lovingly with petroleum jelly to help prevent rust from forming in your bond in the first place.
7. If the nut is STILL bonded to the bolt, you may need to "pack some heat." Heating one side of the nut can expand it enough to break the rust bond or melt locking compound. NOTE First, be sure to clean off all the WD 40 and only use open flame in safe areas.
Many modern cars have extensive amounts of plastic that can melt andor catch fire. As your vision is narrowed by dark safety glasses, (you ARE wearing your safety glasses, aren't you!) Have a spotter watch for smoke or flames. Fireproof welder's blankets can also be used to protect vital car parts and paint. A hand held propane torch should work nicely.
8. Another "trick" for removing rusted NPT pipe plugs from cast iron is to heat the surrounding iron, and melt a candle over the threads. Paraffin wax will wick into the threads and act as a lubricant! Be sure to use a snug fitting, proper sized socket.
9. A "last resort" for removing a rusted nut is a pneumatic or electric impact gun, because it often breaks the bolt. Since these tools can be quite powerful, they are reserved for larger nuts. (Need I say anything funny about "powerful tools" being best matched with "larger nuts") If possible, use the impact on the nut side and hold the bolt with a wrench.
10. OK...By this point, hopefully, you've got a screw loose...I know I do!
This article was writen by Lynn