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amodoko 08-19-2011 06:20 AM

Best way to get off a tight bolt in cramped workspace, under car
Hey guys, I'm about to install a hitch on my car. I'm literally stuck at the beginning of the installation though due to some stuck bolts. In order to install my hitch, I need to first remove the bolts in the rail brackets under my car, so the hitch can be attached there. First off, there are 4 bolts, 2 on each side of the car. They are a bit rusted, so I sprayed some WD-40 on all bolts to loosen them up a bit. The 2 bolts on the driver side of the car were easy to remove, but required A LOT of torque on my socket wrench. But the two on the passenger side of the car are right above my muffler, so I can not get good access to them. All I could properly fit in there was a regular wrench, it fits fine, but I can not get enough torque for the life of me to get those darn bolts off. I tried and tried, and they would not budge. It is just such an awkward space because of how tight the workspace is in there. I even considered removing my muffler, but that is just ridiculous since it is welded on there.

So what I need to do, is find a way to properly loosen these bolts, so they will easily unscrew. What's the best way to do this without spending too much money?

I'm open to buying new tools, just not something super expensive. I have a bunch of basic tools and wouldn't mind adding some more to my collection.

But either way, what's the best solution to get these bolts off? It really is a tight work space, I couldn't even fit a socket wrench on the bolts.

oh'mike 08-19-2011 07:08 AM

That's why the mechanics get the big bucks----use a pneumatic impact gun---you may need to remove the muffler (or lower it ) in order to get an extension onto the bolt.

Mr Chips 08-19-2011 07:08 AM

Can you remove any of the muffler straps, so it will hang down a little and give you room to get in there?

oh'mike 08-19-2011 07:10 AM

Cutting off the bolt is an option but make sure you don't have a gasoline leak anywhere.

fabrk8r 08-19-2011 07:36 AM

Try a little automatic transmission fluid and some heat from a small propane torch. The heat will help wick the transmission fluid into the threads through capillary action. This is the second best rust penetrating method I've found. The very best is to mix a little DOT-3 brake fluid with the transmission fluid, but it will really smoke and stink when you apply heat. Transmission fluid alone is usually enough if you give it a little time to work.

It will also help if you can rap on the head of the bolt with a hammer while turning it.

Mr Chips 08-19-2011 07:52 AM


Originally Posted by fabrk8r (Post 710663)
Try a little automatic transmission fluid and some heat from a small propane torch. The heat will help wick the transmission fluid into the threads through capillary action.

i was going to suggest propane or MAPP as well, but figured because he was working in the back he might be close to the gas tank or fuel lines.

If you have the space to do it safely, I highly recommend this method

DexterII 08-19-2011 01:30 PM

ATF and some heat will work, but I too am reluctant to use it near the rear of the vehicle, or, for that matter, pretty much any place on a vehicle today, because, besides just the fuel tank, there are too many places on today's vehicles where you are not far from a brake or vacuum line, sensor, seal, or other component that can be quickly damaged by excess heat. The first thing I would try is Break-Away, or similar rust cutter, which you can purchase at any auto parts store or hardware; let that soak a few hours, and apply some more, then try the bolt or nut again. If you don't see a need for one in your own future, and don't no anyone who has one, check with your local rental store to see if they have an electric impact wrench available; the hammer action does wonders in such applications. For future reference, keep in mind that the WD in WD40 stands for "water displacement", or something along that line; it is great for spraying hand tools, shovels, etc., to prevent surface rust, but is certainly not the best lubricant, and, although a very good product for its' intended uses, is pretty much worthless when it comes to freeing a rusted bolt or nut.

DexterII 08-19-2011 01:37 PM

Just happened to think too that if you cannot get the exhaust far enough out of the way for an impact wrench, and are restricted to just combination wrenches, position the wrench on top such that when you turn it, it will move against the frame, so that you don't have to do anything with it, just be sure that it is not against a brake or fuel line or any wires, then put your wrench on the bottom, and if you need more leverage, you can insert the open end of that wrench through the box end of a similar size wrench. I always hate doing that, only because it is probably not the way that they were intended to be used, but it works when you are in tight confines. Some taps with a hammer, preferrably a plastic or rubber one, can help too.

Jackofall1 08-19-2011 01:44 PM

The absolute best penetrating oil I have ever used is called "Kroil" not exactly sure where you can purchase it, I did do an online search and you can order it that way.Did you put a pipe extension on the wrench to get more leverage?Mark

D-rock 08-19-2011 05:26 PM

I agree with the majority here....but all I would caution is if using a wrench, be sure to use a solid six point wrench or you may round off the bolt

ukrkoz 08-19-2011 05:31 PM

1. you sure you have the right bolts? they might be wrong ones, like bolts for rear seats, that are WELDED to the subframe
2. please, don't ruin your car by cutting bolts off.
3. please, do not take chances with blow torches and such underneath there
4. if you are positive you have the right bolts, and you do must undo them, remove that exhaust pipe. trust me, will be less hassle this way. now, that you have decent access to those bolt heads, buy yourself (Sears) set of those:

as you will take major chance on stripping bolt heads and NOW being REALLY stuck. with Griptite - you'll "gid id done". also, fix yourself cheat pipe and take some copper or bronze hammer to those bolts heads. will loosen them up some.

Btw, what are those attached to? Is there a better way of undoing them from inside the car, I mean - undoing maybe nuts that hold 'em in place? As I do not know what car is it.

Master of Cold 08-19-2011 05:37 PM

WD40 is made from fish oil.

amodoko 08-19-2011 07:01 PM

Hey guys, thanks so much for all the great replies. This is more information than I was expecting to receive, so I greatly appreciate it. To answer some of your questions, I'm pretty sure the bolts are supposed to be removable, but I'll check when I get home later tonight (been a long day at work). I am going to refrain from using any kind of flame around that area for now, and use some more safe approaches to see if they work first. I'm going to put some auto trans fluid around the bolts since I know I have some in my shed at home, and I'm also going to try to remove any supporting devices around the muffler to see if it will hang lower, thus giving me better access to the bolts (then I can use a socket wrench like I did on the other, more open, side). Maybe the ATF will help even without putting a flame to it. I really do appreciate the help, you guys are awesome.

westgateblvd 08-20-2011 08:25 PM

WD-40 is a lubricant. Not a rust penetrator. JB Power Blast is a good one. You can find it at a auto parts store. Like a few have said.. A 6- point socket would be the best. Use a 1/2" breaker bar. By using a breaker bar you can also put on a legnth of pipe to jack up the torque on the bolt. Now hith this removal.. Can you see the nut?? You can spray whatever you want on the bolt head, but will mean nothing to the nut. If you need to.. You might have to drill at least a 3/8" a couple of inches either way that is easier for you to see if there is a nut there. That is where the spray needs to be. Then when putting in the new bolts.. Wrap some thin wire around the bolt threads and fish it through the frame to where the bolt needs to come threw. Once the bolt falls into place.. Just unwrap the wire from the bolt threads.. Al

Master of Cold 08-20-2011 08:37 PM

What also works is to get the bolt hot and spray it with liquid refrigerant. Works every time..

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