Removing An Old Oil Furnace: Removing Fuel Oil Tanks From A Basement

By Bruce W. Maki, Editor

Question:  What's the first thing to do after you discover that your fuel oil furnace has conked out?

Answer:  Start remodeling the basement, the basement stairwell, and anything between the furnace and the back door.

At least that was our approach when the old oil-burning monster died. We had been contemplating switching to propane, and this forced the decision.

The old furnace was quite large, about 3 feet wide by 6 feet long, and over 3 feet tall. Not being sure if it could be dismantled, we knew it would not fit up the basement stairs, through the door at the top of the stairs, and around the corner to go out the back door. It seems that about 10 to 12 years ago, long after the oil furnace and tanks were installed, the previous owner had built a dividing wall at the top of the stairs and installed a door. This created a small entry vestibule at the back door, but there was no way we could haul the furnace or oil tanks out with this partition in place.

Even if we wanted to keep a partition at the top of the stairs, the wall the previous owner built was so poorly constructed that we decided to tear it out and build something better.

So soon after the oil furnace died, while we waited for the heating contractor to fit us into their schedule, we demolished the partition and tore out all the wall surfaces around the stairwell. After opening up the stairs, we began to think about leaving the stairwell open, and building some shelving and storage into the area. But that is a project for another article.

It turned out that the old oil furnace was easy to dismantle. It was basically a sheet metal box surrounding a heavy steel heat exchanger. The heat exchanger was about one-fourth the size of the whole furnace, and was the largest and heaviest single piece. The two of us were able to haul it up the stairs with no problem.

But the oil tanks were another issue. These tanks were about 28 inches wide, 48 inches tall, and about 60 inches long. When the heating guy installed the new propane furnace, I mentioned how we would someday be hauling out the old oil tanks. He laughed and said "Don't call me!". 

I figured I was in for a battle.

The oil tanks in the basement. Note all the concrete splattered on the tanks. A previous owner poured a concrete floor in the basement, but not under the tanks. The tanks rested on cement blocks placed on the original dirt floor.

I used a big 36" aluminum pipe wrench to remove the fill and vent pipes.

Disconnecting the fill and vent piping was no small deal. The fill pipes were 2 inch diameter threaded steel pipe, and the vent was 1¼ inch pipe. After disconnecting the union fittings (the fitting in the picture above) I unscrewed whatever fittings and sections of pipe that I could turn. As a last resort, I could have simply cut all the pipe with my reciprocating saw, but unscrewing the pipes is faster.

Each tank had a shut-off valve at it's outlet (note the red handles) though they were different types of valves. The larger red object in the right-hand photo contains a replaceable filter.

Using an adjustable wrench I removed the flare fittings that connected the copper tubing to the tee. I placed a small shallow container below the tubing to catch the oil.

I was able to remove the shut-off valves with a wrench. There was a ½ inch pipe thread on the other end of the valve, which later proved to be useful.

Not having a clue how to approach this, I tried lifting one of the tanks. To my surprise I was able to lift it by myself. I placed some blocks of wood under the steel "feet".

Getting A Handle On Things:

I connected some short pieces of ½ inch black pipe to the drain line. This will form a handle.

Outside, I removed a section of the fill pipe, and some elbows.

I attached some pieces of 1¼ inch pipe to the fill hole on the tank, to make an upper handle.

I had to buy an adapter to connect the 1¼ inch pipe to the 2 inch opening on the tank.

With these two handles attached to the tank, I was able to easily drag them across the basement floor. What I could not do was take a picture of myself doing that.

The monster challenge: The basement stairs... with very low headroom. There's a couple of oil tanks that want to leave the basement. I'm home alone, I won't have any helpers for a couple of days and I don't want to wait.

The view from the basement, looking up. The arrow points to the back door.

The monstrous solution: Mechanical Advantage: With the tools I have, I can lift all sorts of things. I knew I could lift the tanks with a cable winch (a.k.a. "Come-Along"), but I needed an anchor point that was sturdy enough. This door jamb was chosen for the job. I pried off the door stop trim and bolted this big automotive tow hook into the framing, using 6 inch lag screws.

This door jamb is just above the top of the stairs. The red arrow points to the hook. I chose this anchor location because I realized that I could shoot a straight line from that door frame down to the bottom of the stairs.

The oil tank at the bottom of the stairs. Since the tanks were only about 28 inches wide, and the stairs were over 36 inches wide, I figured I would need to prevent the tank from slipping sideways. So I placed a long 2x10 on the side of the stairs (red arrow).

Using only muscle power I was able to get the tank started up the stairs, but no farther. Even with the convenient carrying handle, there was no way I could lift this 120 pound mass uphill.

The view from in the basement.

At this point I realized that the "handle" was going to hit the ceiling on the way up the stairs.

I used this short piece of 5/16 inch chain to provide a means of grabbing the oil tank.

To apply a uniform pulling force, I hooked the short chain to the front feet on the tank...

... and I hooked the cable winch to the mid point of this short chain. I knew that I needed to pull on the center of the tank, or else it would turn on me.

The other end of the winch was hooked to an extra-long section of 5/16" chain, which was looped over the tow hook. Of course, I began this operation with the winch's cable fully extended.

I just cranked away on the winch and the tank moved up the stairs. But...

The tank kept leaning to the side, so made a "guardrail" by laying a 12-foot 2x10 on a short piece of wood (hidden below the front end of the plank). This short "outrigger" board was held in place with a couple of cement blocks.

It took only a few minutes to get the tank past the narrow headroom point.

At this point the cable winch had been completely wound up (the two red arrows point to the fixed and moveable parts of the winch, and they are close together). I had to stop and reposition the chains.

Just in case... I placed a long heavy steel bar under the short chain loop, to hold the tanks from sliding back down the stairs. But the back edge of the tank just happened to get wedged into place, so there was no weight placed on this chain.

I again extended the winch's cable and connected it directly to the tow hook, and hooked the other end to the rusty old loop chain.

I continued to crank on the winch and the oil tank climbed higher up the stairs.

This was about as far as I could hoist the tank. In this picture you can get a better idea of how the tank was rigged.

This is one of the four "feet" under the tank. These made convenient grab points for the hooks.

This picture was taken from just outside the back door. With the chain and winch still connected, I swung the tank towards the back door and slid it outside. I didn't even need to remove the back door from it's hinges... and it was a 32 inch door, only 4 inches wider than the oil tank.

These tanks were fairly easy to move around, though I couldn't lift the entire weight. I was able to "walk" the tank by lifting one side and then the other. Here I screwed some handles back in place to help move the tank.

The Damage Is Done:

However... Moving these two oil tanks from the basement caused some damage. The stair treads got rather chewed up from the heavy weight being dragged across them.

The tank left some scratches on the basement floor (top arrow) and some small puddles of oil (bottom arrow). Oil spills won't dry up, and they may leave an odor for many months.

I routinely use a spray can of automotive brake cleaner (which is very volatile and may be highly flammable) to remove oil spots from concrete. I spray the brake cleaner on the spot and immediately wipe it up with a paper towel. Brake cleaner removes most of the oil, but there is usually a slight stain on the concrete.

The door jamb was not as secure as I first thought. The jamb pulled away  from the casing, leaving a gap (arrow).

But none of these minor problems were any cause for concern, because all of these areas either need remodeling or are utility spaces that don't really matter. This is an important issue for many people, however, because not everybody is willing to remodel part of their house just to remove an oil tank.

The relevant point is: If a house has good finished surfaces between the oil tank and the back door, it would be wise to have several people available to help move the tank. Protective measures such as rugs or scraps of carpet could be employed to prevent damage.

The oil tank area after the tanks were removed. The corner was a mess. It had collected debris and junk for about half a century.

When I hauled away the tanks, I loaded them both in my tiny 4x8 utility trailer and strapped them in place with ratcheting tie-down straps. I would have preferred to lay the tanks down, but they both would not fit, and I didn't want to make two trips.

To keep the straps from slipping out of place, I threaded the straps through the holes in the feet.

Cleaning The Oil Tanks:

While this is probably not necessary, I attempted to clean the oil tanks, just to see if I could. I started by hauling the tanks far into the back yard. We live on an old farm, so there's lots of open land here. I strapped each tank to my fridge dolly and hauled them out back beside my bonfire pit. Then I poured a gallon of mineral spirits into a garden sprayer (the sprayer instructions loudly warn against spraying combustible liquids, but... I live on the edge) and poked the sprayer nozzle into the various openings on the tanks. I sprayed the insides from top to bottom, then I flipped the tanks over a couple of times (end over end, to avoid spilling liquids). I drained the tanks over some newspapers and scraps of wood, so the liquid could be burned off. I suspect it's better for the environment to burn such petroleum products rather than let them evaporate.

Next I poured about a quart of denatured alcohol into the garden sprayer and sprayed the alcohol. into the tanks to rinse away the mineral spirits and oil. This certainly helped, but a quart of alcohol was not enough to do the job. I drained the alcohol over the burn pile, rolled the tanks a safe distance away, and ignited the liquid waste.

Later, I put some Simple Green in the garden sprayer, not diluted at all. Simple Green seems to be a good water-soluble degreasing agent. I sprayed the insides of the tanks and then rolled the tanks around the hayfield, this time letting stuff come out the large holes on top. Large chunks of black charcoal-like gunk came out. I rinsed the tanks several times with a garden hose.

Now the tanks smelled of a combination of Simple Green AND fuel oil.

After I hauled away the tanks, the back yard smelled faintly of fuel oil. There were numerous spots of black oily gunk in the field. I used a propane torch to burn off these oily spots (being careful not to let grass fires get started), and that seemed to remove the odor.

Was this the best thing to do? I don't know. If I was going to cut the tanks open, I could have wiped the insides clean with rags or newspapers.

Disposing Of Old Oil Tanks:

I was able to dispose of the old tanks at a local metal recycling company. Normally they require that all tanks be cut in half, but they made an exception for me because I had given them over 100 gallons of unused fuel oil. Besides, the manager knew somebody who might be able to use them, so they accepted the tanks intact.

I have seen people make large trailer-mounted barbecue grills from oil tanks. They cut the tank in two, turning the top half into a hinged lid, and install supports for metal grills. This was of no interest to me, but I seriously considered placing an advertisement in the local paper to give away these tanks. But... I just didn't have the time to fool around with such things... I just wanted them gone. Whatever happens to these old tanks, at least the steel will be re-used or recycled.

Disposing of large items like oil tanks could be quite a problem. I doubt the garbage haulers would take an oil tank if you left it by the curb. It would be wise to find someone to take the oil tank before removing it from the house.

Cutting these tanks would be time-consuming, but not impossible. An oxy-acetylene torch immediately comes to mind, but I would NOT recommend using a torch to cut an oil tank. A cutting torch could easily ignite leftover fuel inside an oil tank, and any kind of fire inside an enclosed chamber could be explosive. Besides, there could be other liquid residues in the tank, liquids that are much more volatile than fuel oil.

I have cut plenty of heavy-gauge steel with my Sawzall. The trick to cutting (or drilling) heavy ferrous metals is :

• Use a sharp, fine-toothed, metal cutting blade. Bi-metal blades are the best because the teeth are a harder metal than the blade body.
• Use a slow cutting speed, to reduce overheating of the blade. The higher-priced Sawzalls have a control dial that limits the maximum speed. When cutting iron and steel, I use 3 on the scale of 1 to 5.
• Push hard on the cutting tool.
• Lubricate the HELL out of the cutter. I often use WD-40, but any oily substance will help. Plain water will work too, but it will rust the blade if not wiped off after use. Sometimes I use a waxy lube stick that is meant for lubricating doors and hinges. I keep a tube in the Sawzall case and just rub it on the blade. In a pinch, spitting on the blade is better than nothing. I'm not kidding!
• In a nutshell: If you want to dull your cutting blades: cut ferrous metals at high speed, don't push very hard, and don't lubricate the cutter. The blade manufacturers will love you.

One problem with cutting these oil tanks would be the weld seams at the corners. When steel is welded the nearby metal becomes much harder, and the weld metal itself is usually very hard. I suspect this would destroy most reciprocating saw blades, even bi-metal blades. My approach would be to use an abrasive cutter in the weld area. I have an inexpensive pneumatic 3" diameter abrasive disc cut-off tool. This tool only cost fifteen bucks, but it requires a large air compressor (this is perhaps the most powerful tool I have; it makes my 4 HP air compressor run nearly full time). An angle grinder would also work, or an abrasive blade could be used on a circular saw. In fact, the entire cut could be made with an abrasive metal-cutting blade mounted on a circular saw, but it might be slower than a Sawzall. Besides, these abrasive blades throw sparks, and too many sparks might ignite traces of oil in the tanks.

Copyright © 2003  HammerZone.com

Written May 29, 2003
Revised January 3, 2006