Common Coleman Liquid Fuel Camp Stove Repairs

Frank Ross
vintage coleman stove

When you have a problem with your Coleman liquid fuel or dual fuel stove there are only a few areas that can be problematic, and even the mechanically challenged can fix them fairly easily. Simplicity in design and ease of repair has contributed to the Coleman stove's popularity and longevity so don't let a minor problem interrupt your camp cuisine. When your stove fails to perform, there are three common problems areas where you should target your troubleshooting efforts: the fuel tank, burner and generator.

Fuel Tank Issues

Assuming that you've filled your tank with fresh fuel, the two most common tank-related problems are failure to create pressure and failure to hold that pressure once it has been achieved. When a stove is operating properly you should not have to pump the tank again once a blue flame has been attained.

Failure to Hold Pressure

If you're able to pump up the tank but find that it leaks down quickly, there's a simple technique to determine what is causing the leak.

Troubleshooting:

  1. Mix 1/2 cup of water with a teaspoon of dish soap and brush, daub or drip the solution on the shaft of the pump plunger while the tank is pressurized as much as possible.
  2. Watch carefully for telltale bubbles.
  3. Apply the soapy mixture to the hole in the end of the plunger shaft (after making sure the valve is closed), around the shaft and around the brass control valve where it screws into the top of the tank.
  4. Turn the tank upside down and check for bubbles around the underside of the filler cap, as well as the valve seat at the bottom end of the pump shaft.
  5. If you notice bubbles around the valve stem you'll need to replace the O-ring seals that prevent fuel from leaking past this shaft housing.

O-Ring Replacement:

  1. With the tank removed and relieved of pressure, remove the tip end of the generator tube with a 3/8" box-end wrench or socket.
  2. Use a ½" open-end wrench to remove the collar that holds the fuel adjustment valve in place, turning the wrench counterclockwise.
  3. Carefully remove the valve, which is connected to a long metal generator stem, taking care not to damage the needle valve on the tip end.
  4. Grip the generator stem firmly with a pair of pliers and turn the valve counter-clockwise to separate the valve assembly from the generator stem.
  5. Remove the screw that holds the valve knob in place and slide off the collar. Inspect and replace the O-ring inside the cap, and also the one on the shaft of the valve stem.
  6. While some parts are interchangeable between the 2-Burner Coleman stove, the 3-Burner Coleman stove and the Dual-Fuel model, it is best to go to the specific model parts list so you don't have incompatibility issues cause by being close, but not exactly right.
  7. Reassemble in reverse order.

Tip: When the pump plunger is tightened too much the valve seat can be damaged, resulting in minor pressure leaks. Once you've determined what is causing the leak, repair kits are available for the cap, plunger, and valve.

Failure to Build Pressure

It is best to fuel and pressurize the tank while it is removed from the stove.

Troubleshooting:

  1. First, make sure you have fuel in the tank and that it is fresh. Tanks should be stored empty and under pressure to prevent clogging and lacquer buildup and because fuel goes stale over time.
  2. If you stored your tank with fuel, empty the tank and dispose of the old fuel properly and refill the tank with fresh Coleman fuel. While you can use gasoline in the dual-fuel stoves, never use anything but Coleman fuel in the traditional liquid fuel stoves.
  3. Next, inspect the rubber washer on the tank fill cap to make sure it is not badly compressed. If it is damaged, you will need to replace it.
  4. If your cap washer is in good shape, put the cap back on and make sure the vent screw on the cap is tightened. Note that these caps should only be tightened until snug. Excessive tightening can damage the cap washer and cause it to leak.
  5. Make sure you've turned the pump plunger shaft at least one complete turn counterclockwise before pumping.
  6. Check the position of your thumb to be sure it is completely covering the hole in the end of the pump plunger.
  7. Now, give the plunger a few quick pumps until you feel firm pressure. You should start feeling the pressure increase fairly quickly. If you don't feel this pressure begin to build up within 8 to 10 pumps, your problem is most likely with the cup at the end of the plunger.

Lubricating Plunger Cups:

There are two types of plunger cups. Older model stoves use leather cups and newer stoves use black neoprene. Leather cups tend to dry out and don't expand enough to provide a good seal. Neoprene tends to harden over time. Both types need to be lubricated.

The simplest solution is to lubricate the plunger cup without taking it apart. The purpose of this procedure is to get all sides of the cup and the pump shaft well lubricated.

  1. Use a good quality leather oil or light machine oil such as 3-in-1 Oil.
  2. Add a few drops to the oil hole next to the pump shaft and slowly raise and lower the pump plunger while rotating it as you stroke it up and down.
  3. Let the oil soak in for a few minutes and try pumping again.

Inspecting the Pump Plunger:

If the above procedure fails, you'll need to pull the pump plunger out and inspect the cup for cracks and flexibility. The critical issue is for the cup to be flexible, without any perforations on the edges that could allow the pressure to bypass down the cylinder wall. If the stove has been stored for a long time the cup may be too dry or damaged to rescue.

  1. The pump plunger is held in place by a small wire bail shaped like a large C. Note that very old stoves may have a small sheet metal screw holding the pump shaft housing in place. For newer stoves, use a pair of needle-nose pliers to gently pull the "C" clip far enough to remove it. For older stoves you only need to remove the retention screw and the rest of the instructions are the same as the newer models.
  2. Inspect the cup at the end of the shaft for cracks or uneven edges.
    • If no physical damage is noted, lubricate the cup and determine if it will expand enough to fit snugly in the pump shaft.
    • If there is damage, you will need to replace the cup. Vintage leather replacement cups can be purchased and are fairly inexpensive. Newer type pumps have a neoprene cup, and a pump repair kit can be found on Amazon for less than $10.
  3. If your tank had rust or corrosion you should remove the shut-off needle valve from the tank. Do not put much pressure on this valve or it will bend.
    1. You'll need to slide the plunger back into the tube and turn it to the left to start backing it out.
    2. Once it's loose, you can use a pair of needle-nosed pliers to gently remove the valve from the pump shaft.
    3. Once you have it removed, inspect the needle at the end and make sure there are no ridges cause from over tightening.
    4. If it's undamaged, clean it off and carefully reinstall it into the tank.
  4. Once removed, inspect the valve seal at the end and determine if it has been damaged. If not, wipe it clean of any crud buildup of old fuel and reinsert it. Damaged seals should be replaced.

When repairs are complete and you've refilled the tank and pumped up the pressure, tighten the plunger clockwise before use. Make sure you don't over tighten it. Too much pressure on the valve at the end of the stem will damage it and cause it to leak pressure and fuel.

Safety Tip: Coleman fuel is very volatile and fuel leaks can lead to a fire outside of the burner, which can be very dangerous. After any repairs, before you strike a match, make sure there are no fuel leaks. Also, never fill the fuel tank near any open flame or source of ignition such as a cigarette or the smoldering coals of a campfire.

Generator Issues

If your stove lights, but the flame remains as a tall, yellow color and refuses to turn an even, bright blue your prime suspect will be the generator. The generator is the tube that extends from the tank to the gooseneck in the stove and is positioned above the right burner on two-burner stoves. On three-burner stoves, you'll find it in the middle burner. This device, when heated, turns the liquid fuel into a pressurized vapor that produces the correct flame and also maintains the tank's pressure.

Replacing the Generator

If time or money isn't an issue, a replacement generator can be had for less than $20 on places like eBay and Amazon.com, but you can also find them at local hardware stores and many sporting goods retailers. If you are replacing your generator, follow the following disassembly steps for reconditioning the generator, and jump down to step 9 since and install your new generator since you won't have any cleaning to do.

Reconditioning the Generator

You may be able to re-condition your generator rather than purchasing a new one. You'll need to disassemble the generator, inspect the parts and clean or recondition as needed.

  1. Remove the tank from the stove and bleed off any pressure.
  2. Use a 3/8" socket or box-end wrench to remove the tip end of the generator.
  3. Use a ½" open-end wrench to remove the collar that holds the fuel adjusting knob in place.
  4. Hold the fuel adjusting knob and pull gently until it is all the way out.
  5. Clean the shaft by rubbing it with a piece of steel wool. Stroke the shaft in only one direction toward the end, taking care not to bend or damage the small needle valve on the tip end.
  6. Remove the spring inside the tube by tilting the tube downward into your open hand.
  7. Once removed, clean the spring with a wire brush or piece of steel wool. Make sure you remove all steel wool and rust residue before reassembling.
  8. Clean the tip end of the generator with break cleaner and inspect it to make sure the tiny hole is clean and clear.
  9. Reassemble, taking care not to bend the tip's needle valve. Tighten carefully.
  10. Refuel, pressurize tank and start the stove to confirm results.

Burner Problems

Burner problems occur quite often, and are the easiest of the three types of issues to address.

Clogged Burners

The most common issue with burners is the flame doesn't spread completely around the entire burner because the small holes in burners often get clogged up from spills or corrosion over time. To take care of this problem, you'll need a flat-bladed screwdriver. Make sure you use one that fits the slot both in width and thickness. Burners endure a tremendous amount of heat and contraction, and rust is not uncommon on burners. If you try to use a blade that's too small you could damage the screw and after that point the process can get ugly.

  1. Remove the burner screw and set it aside in a metal cup or anywhere it will not roll off and get lost.
  2. There are a number of wafer discs, one flat and one curly, alternating in a stack. Remove these wafers and clean them with a wire brush carefully, being sure not to bend the curly wafers.
  3. Check the bowl of the burner for debris and make sure it isn't obstructed.
  4. Once the wafers are cleaned up, re-stack them in alternating order starting with the solid one first.
  5. Re-tighten the screw when you've got the wafers lined up properly and fire the stove up to check your work.

Tip: One of the handiest things to have on a camping trip is a Coleman utility lighter. You don't have to use the Coleman brand. It's the length of the shaft that keeps your hand and the hair on your arm from getting singed when the burner flames up on ignition. They're also great for starting campfires and especially useful for lighting Coleman lanterns.

Re-lighting Issues

Coleman stoves are often difficult to re-light soon after they've been turned off. This is one of the easiest problems to solve; just wait a few minutes for the residue of fuel to evaporate from the fuel bowl and the expansion chamber or gooseneck as it is commonly called.

Spitting/Popping When Lit

Sometimes burners start popping or spitting. If the popping noise isn't too severe you can just let the fuel burn out and deal with the problem after your meal is prepared.

  • This problem is commonly caused by water in the stove from rain or morning dew. Water can also build up in fuel as condensation in the tank when the lid is left off too long on hot days.
  • Another possibility is too much fuel in the reservoir, or the burner bowl isn't positioned correctly. Evaluate and adjust as needed.
  • Sometimes this problem can be caused by the generator not being properly inserted into the stove manifold, so check to make sure it is installed correctly.
  • If none of the above solutions solve your problem, check the tip end of the generator to see if the tiny hole is partially clogged.

Preventive Maintenance

Poor care and maintenance are the greatest factors that create problems with Coleman stoves. Cooking on any surface creates the opportunity for spills and splashes that can contaminate burners, cause rust and clog small openings in burners. This is especially true for camp stoves, where conditions are not always ideal and stability of the stove can sometimes contribute to unfortunate overflow of pots and skillets. Coleman camp stove burners are subjected to intense heat and these metal parts are prone to rusting so clean up spills as soon as the stove cools down.

The first step in eliminating future problems begins with the end of a camping trip.

  1. Wash out the inside of the stove, removing grease and splattered food particles with a mild soap.
  2. Spray the burners with a light coating of WD-40 to reduce rust during storage.
  3. Empty the fuel tank and store the tank under pressure, which reduces the impact of lacquer buildup in the fuel valve system.

These things are best done before loading out of a campsite because once you get home, tired and ready for the shower, the chances are you'll head for the bed or recliner once you've unloaded and not be willing to take the proper steps afterward.

Dealing with Lacquer Build-Up

When fuel is left in the tank for long periods lacquer builds up on the inside surfaces of the tank and needle valve and you will have to remove it.

  • If the buildup is not too bad you can clean it out with carburetor cleaner. Stubborn deposits may have to soak overnight.
  • Another trick is to put a cup of fuel in the tank and drop a length of small chain in the tank, replace the cap and shake it violently for several minutes turning it over as you go. Dump the fuel, rinse it out with more fuel to be sure you've removed all small particles loosened in the process.

Once you've gone through this process, you'll see the wisdom of storing tanks empty and not have to do it again! Coleman stoves are real work horses and it's not unusual to have them last 30 years or more with proper care.

Test Before Traveling

It is best to test your stove before you're on your camping trip surrounded by hungry people who want to know why the stove isn't working and what you're going to do about it. Failing that foresight, the solutions to most problems are not that difficult in the field, unless replacement parts are required. In that case, warm food on this camping trip will require some additional effort on your part, assuming your fellow campers haven't strung you up by your heels.

Common Coleman Liquid Fuel Camp Stove Repairs