If you are a lover of older 4WD’s like us, you are probably just about ready for a handful of DIY projects to refresh your suspension components, and possibly even an upgrade of your exhaust system to give the old girl a bit more grunt when you hit the tracks.

But if you’ve ever driven your 4WD offroad, or even the previous owner has, chances are that some, if not all the fasteners on the underside of your vehicle will more than likely have some level of rust or corrosion preventing easy removal.

Rust forms because of a chemical reaction on metal,  if many different situations which can range from salt water, corrosive minerals in mud, and even from situations such as just being dirty from road grime and rain water, or different metals such as high carbon steel and zinc coatings being present in the same location.

Where rust forms!

Rust is a malevolent beast and due to its cancerous nature will spread like a wildfire through any iron or steel that is exposed to the air. But how does it form, and where should you be looking for it?

Rust is caused when chemicals, such as salt and other corrosive materials begin eating away at the surface layers of steel or iron, and makes oxygen start to bond to the iron element within the bolt.

Because of the electrolytic reaction that happens, these chemicals like sea salt and corrosive mud, can be diluted to a point where they wick their own way into the threads of your fasteners and cause the oxide layer to build up inside the joint of the fastener, effectively chemical welding the threads together, resulting in what is affectionately known in the industry as a “stuck nut”.

Penetrating Spray

There are dozens of spray on miracle cures that are available on the market, which supposedly creep into the micron thin space between the thread surfaces and dissolves the iron oxide layers allowing determined handymen to break free the seized fastener.

These penetrating sprays can be excellent at getting the threads cleaned and coupled with a hand-held wire brush can allow you to clean up the threads at least to a point where it can be undone and then replaced.

Whilst these sprays may work well, there is room for using a standard solvent like kerosene or brake cleaner to dissolve some of the more powdery surface rust you might encounter and potentially opening up the ability to break the nut loose.

One of the biggest things with penetrating spray is to soak the rust, and be patient, when you think you have enough use a bit more and be patient, as in, come back the next day and hit it again with the spray, it pays to not rush these things if you have the luxury, as the longer the spray has to set in, the more effective it will be at breaking loose the rust.

A Tool for every job

One of the biggest things preventing a nut from being broken free, is using the wrong tool for the task. Its surprising just what the correct spanner or screwdriver can do even to an incredibly corroded fastener. However, it is important to know that if it isn’t coming loose, sometimes a bigger lever can increase the likelihood of shearing the top off the fastener.

If you have a choice for the tool you are using, it is a great idea to pick a socket or ring spanner that has as much surface area in contact as possible this decreases the likelihood of rounding the nut off, this goes for screw fasteners that have a Philips or flat top as well, if you choose the correct size tool for the fastener you will ensure it grips the head of the fastener nice and tight offering the best possible torque transmission into the fastener for the cleanest release.

Shock Treatment

When in doubt, get a bigger hammer. This is a time tested method that works in a lot of cases, with a quality socket set you often have a solid nut breaker style extension bar, the extra leverage you can get from one of these is incredible and will more than double your mechanical advantage and supply much more torque to the fastener.

Buy how do you use a hammer to free a rusted nut??

Concussive force on the head of the bolt or applied directly to the nut will often provide enough of a sheering force to actually “crack the rust free” you’d be surprised just how often this little trick of rapping on the head of the fastener with a hammer blow.

This handy little trick is an incredibly useful tool in the arsenal and will improve your success rate in getting old and rusty fasteners free on your 4WD.

Working the threads

If you have a fastener that moves, but is seemingly impossible to completely remove, it is worth working the threads up and down. Go back to step one where we hit the threads with a wire brush, this will clean as much crud out of the way as possible and hit it again with some penetrating spray.

With a bit of cycling the nut up and down, you are effectively re-cutting the threads using the nut, into the rusty surface.

Thermal treatment

Just like using a big hammer, a little bit of heat never hurt a rusty nut – heating up the head of a bolt or the metal that it is threaded into uses the thermal properties of metal expansion to release the rusty bond between the two fasteners.

By heating the head of the bolt up you effectively swell the bolt in the hole, once it has cooled down it shrinks back down and if done right your bolt will simply unscrew like normal.

A Bigger hammer!

Sometimes a hammer or gentle heating just won’t get the bolt free, this is where the big dogs come in, to completely remove an extremely stubborn bolt, via cold chisel, angle grinder or your oxy-acetylene torch with a cutting flame.

The old saying goes “when the only tool you have is a hammer, everything starts looking like a nail” rings very true with stuck bolts, and now being equipped with more tools to break your stuck fasteners free, you will be able to install more upgrades to your 4WD.

Ounce of prevention

An ounce of prevention is worth a pound of cure, when fitting accessories to your vehicle using something like an anti-seize compound will stop your fasteners from seizing without affecting the way they tighten in the same way that grease might change the torque required to tighten.  

By also washing your entire vehicle and not just the body panels, you prevent rust from forming, we suggest setting up a backyard sprinkler underneath your vehicle for a half an hour to thoroughly soak the underside, once the caked on dirt has been rinsed, you can then hit the underside with a good application of car washing soap and then blast away with your garden hose nozzle to remove all the stubborn build up.

Get Cracking

Many people who are not used to driving old 4WD’s probably don’t own a full complement of tools for home DIY upgrades such as a Domin8r Exhaust System, or upgraded suspension, or even for bush repairs, this is why we have put together a comprehensive tool kit to give you everything in one place for all your work on your old 4WD!

The Adventure Kings Bush Mechanic Tool Kit includes just about everything you need to get a stuck bolt free, from a large hammer, a full complement of spanners and sockets an extended breaker bar, a hack saw and even a set of locking pliers for rounded off bolt heads and much more!

To find out more about the range of 4WD accessories, head to www.4WDSupacentre.com.au call us on 1800 88 39 64 or even visit one of our stores for the latest range of gear and best possible prices!