200A and 202 reproduction
frames back
in stock.

chloedarling
Hi everyone, I'm new to the world of coleman stoves so bear with me if this is a real easy fix. I just bought a used 420 stove, took it apart to clean and get most of the rust off, and put it back together. Last night when I test drove it it burned beautifully but now the flame goes out soon after lighting it. I've lit the stove several times today and the issue is getting worse - this morning I was able to keep it running long enough to cook a grilled cheese sandwich but now it won't stay lit for more than a couple minutes. If I pump it back up the flame rallies but quickly dies down. 

My guess is that I have a leak somewhere - but where? The tank pressurizes just fine when I pump it, it just doesn't seem to stay pressurized. The rubber cap on the pump assembly looks great, although maybe there's some imperfection that isn't really visible? I've checked the gasket of the fuel cap and it looks perfect, ran some steel wool over the threads of the opening to remove any gunk, shook the tank to see if any fuel leaks anywhere..... I've done everything I can think of short of dunking it in a bucket of water (and I just might try that!!)

Here's a video demonstrating my problem. 
Mute it if you don't want to hear my dad and I talking, although at the end of the video as the flame goes out there's some sort of tapping noise which might be relevant. 

Thanks in advance for any advice y'all might be able to give. 
Quote
Coldwaterpaddler
I did watch the video, but it was dark. Did you close the check valve stem by rotating the pump knob clockwise until tight? 

Also, did you rotate the the fuel control lever downwards after the flame simmers down a little?
Stovie-Steve
"Don't let the weather run your life" - Steve
The Coleman Blues - #95
Quote
TwoCanoes
Looks like you might be running low on fuel.  Many times I've thought I had plenty of fuel in the tank, but the stove ran poorly. Put in more fuel, problem solved.
Quote
austin65uri
Doubt if it's the check valve, as you seem to be closing the pump stem tight after pumping.  Doing the dunk test on a stove tank is easy and may be your best bet.
Bill.
ICCC#1601
Quote
Kgam1020
Hi and welcome from western Massachusetts. Everyone above have a good insight on your problem. I would definitely check the CV valve and make sure it isn’t letting air back out of the tank. Remove the pump and threaded rod, with the tank empty shake it a bit and you should hear the “BB” at the bottom of the CV rattle. If it doesn’t than it is probably stuck letting pressure out. I have had good luck spraying carb cleaner down it with the attached straw and flushing it out. Rinse the tank throughly and let dry before adding new fuel. I agree with @TwoCanoes about the fuel being low make sure you run with a full tank. I had a Similar problem with my 426d and to find out I was just low on fuel when I thought I had enough in it. Filled her up and the stove ran great. 
Ken.
Looking for Bday lanterns, 10/83, 11/84 and 10/2011.
Milspec Syndicate member #1020 
Quote
Smudge
Zulu Kono wrote:
Sounds like you may have a leaking check valve.
After you pump pressure into it,
and with the stove off and cool,
put your ear down next to the pump.
Can you hear air hissing back out?
+1
If you still cannot detect a leak:
Assuming your tank is filled with enough fuel, I agree, the check valve is most likely leaking. The pump knob must be firmly tightened after pumping to seal the check valve.
I don't recommend a dunk test. Instead: Be sure the tank has enough fuel and the pump knob is firmly tightened (closed). After the tank is completely cool, and away from any open flame, and in a well ventilated area (outside); pump up the tank, flip it upside down, and you'll see where fuel is leaking. Be sure to wipe up any fuel and let it dry.

Note: It is normal to have some air escaping from the pump when you're operating the pump. But when you firmly close the pump knob, it should seal.
"If all the beasts were gone, men would die from a great loneliness of spirit, for whatever happens to the beasts,
also happens to the man. Whatever befalls the Earth, befalls the sons of the Earth.” - Chief Seattle

ICCC # 1726  -  Bernz0matiC Appreciation Club #057
Perfection Heater Collectors #6
Quote
rob_pontius
I also want to say that your problem is a bad fuel cap seal. You're closing the check valve and turning the air circuit lever correctly. I'm all for a dunk test as well. Even if you were low on fuel, you wouldn't lose pressure that fast.
Quote
chloedarling
Thanks for your replies everyone. Firstly - yes, I'm closing the pump knob firmly, yes I'm flipping the lever down, and yes I made sure to fill the tank with fuel (because I thought that was the issue as well!). At recommendation of @Kgam1020 I shook the tank to hear the BB rattle, and it did. I've flipped the tank several times to look for leaks and I wasn't able to see one any of those times. @rob_pontius, is it possible for a fuel cap seal to be bad even if the gasket looks good? I thought that could be a problem but the gasket and threads look in perfect condition and I can't hear any air hissing out when I firmly close the cap. 

Thanks everyone.... I'll keep trying
Quote
Coldwaterpaddler
So, let's divide this into two parts. Gas and Pressure. Your question is about why the stove loses pressure while burning.

Question: Is it losing pressure when not burning? That is, with everything off? Remove the tank from the stove. Pump it up twice as much as normal, then let it sit for 30 minutes. After the time is complete open the fuel cap. You should hear a loud hiss. If you do, your fount is holding air pretty well.

Question: after the stove goes out, unexpectedly, and cools for a minute have you opened the fuel cap to see if you get a hiss of air from the fount?

To answer your question, yes I've had fuel cap gaskets look good but not seal well. Typically it's been that the gasket is hard and dried out but still looked nice. If you have another GPA (stove or lantern), try swapping the caps and give it another test.
Stovie-Steve
"Don't let the weather run your life" - Steve
The Coleman Blues - #95
Quote
Smudge
Just to add one more thing. When you first start up the stove( the lever in the up position) you should be pumping more during this time, because during the start-up part period, the tank is depressurizing significantly faster than when the lever is in the down (run) position. After about 30 seconds, when the generator is warmed up and you flip the lever to the down position, pump some more to fully pressurize and it should be fine.
"If all the beasts were gone, men would die from a great loneliness of spirit, for whatever happens to the beasts,
also happens to the man. Whatever befalls the Earth, befalls the sons of the Earth.” - Chief Seattle

ICCC # 1726  -  Bernz0matiC Appreciation Club #057
Perfection Heater Collectors #6
Quote
JimL
As Steve suggested, swap the fuel cap from another Coleman lantern or stove.  They won't mind as long as it's only temporary.  🙂

-Jim

Flammable liquids, open flame, what could go wrong?


I've missed you!  But I'm reloading.
Quote
TwoCanoes
While you're waiting the 30 minutes that Steve recommended, you can test for a leak at the base of the pump tube, where the air stem (the square rod in the pump tube) seats into the check valve.  Keep the valve closed, but remove the pump.  Put a few drops of alcohol in the tube.  If the air stem isn't seating completely, you'll get air bubbling out.  When I have a leak, that's practically always where it is coming from (assuming the cap seals well).
Quote
Majicwrench
You are closing the air stem. It's not the check valve, end of story there.

ALL those old cap gaskets leak.  Pump up tank, put some soapy water around fill cap and watch it bubble.
Keith
Quote
arizonacamper
The easiest thing to do is have some fuel in the tank pump it up about 40 times close off the air stem valve have a bucket of water nearby dunk it in the bucket of water with the fuel cap submerged look to see if you see bubbles. if you do fuel cap and or gasket needs to be replaced. if you don't see air bubbles leak is elsewhere. I personally am a fan of the dunk test. the only thing you have to do is after you pull it out of the water turn the tank on end with the pump facing down pull the plunger out and all the water that's in there will run out and it won't get into the tank.
Shawn 
Owner of Copper State Diesel And Automotive. See my facebook page.

Lanterns are like tools. 
You can not have too many unless your wife says so!!

Gas is what you use for washing parts diesel is for making power!

Coleman blues 243 #147
Coleman 275 appreciation #74
Milspec syndicate #39

Looking for any lanterns or stoves dated 5/63 or 1/72
Quote
zoomkat
The check valve itself is operating as it should as the tank pumps up pretty quickly. The pump needle valve is the positive pressure shutoff. The pump cup seems to seal ok, so to check for needle valve or other leakage, you can pump the tank up, close the needle valve, put a little soapy water on your finger tip, lightly put the finger tip over the pump vent hole, and see if you get some bubbles. As a temporary fuel cap gasket check, you can coat the cap gasket with some grease, Vaseline, or similar, and then see if the tank holds pressure better.
Quote
Macburner
Those stoves have a fuel/air pick up tube and if that is dirty it may not shut off the air when the lever is down. Simple check is to give the stove a shake when it starts to die and if it revives with the extra boost of fuel through the air intake it means your pressure loss is through the generator so it won't show with any kind ofpressure test. ::Neil::

Pluralitas non est ponenda sine neccesitate

 Author-The Pressure Lamp Catalogue (PLC).

Neil A. McRae. ICCC #306. Director International Guild of Lamp Researchers Ltd.

Quote
BSAGuy
Hello and welcome to the CCF from the state of North Carolina (southeastern USA).  My vote would be t replace the gasket in the fuel cap.  Many folks here do that as a first step for any second hand stove.  Even if the gasket looks good, it can be too hard or have some micro cracks that prevent a good seal and thus pressure retention.
- Courtenay
Be Prepared
Quote
Chucker
rob_pontius wrote:
I also want to say that your problem is a bad fuel cap seal. You're closing the check valve and turning the air circuit lever correctly. I'm all for a dunk test as well. Even if you were low on fuel, you wouldn't lose pressure that fast.


This.

Yes, a gasket can "look good" and be hard as a rock from age. Try a fuel cap from another stove or Coleman liquid fuel lantern that is known to run good. You'll have your answer quickly. And WELCOME to the forum!
Chuck
"...we also glory in our sufferings, because we know that suffering produces perseverance; perseverance, character; and character, hope" Romans 5:3-4
Eye-SEE-C-C Member #1333 -- MilSpecOps #003
"Michigan - from the Ojibwa word “meicigama,” meaning “great water.”
Quote
outlawmws
Zulu Kono wrote:
Disagree.
I have a 200A that leaks from the
check valve with the stem closed tight.
Haven't gotten around to fixing it yet.


VERY unlikely to be a leaking check valve unless the seat or stem needle are damaged.  if it's leaking closed, it's FAR more likely to be the CV is not seated properly or a leaking pump tube.  
[Logo%20Outlaw-half] 
Coleman Blue's 243's #341 - 275 Appreciation Syndicate member 0242
FAS #001 Confusing Future Generations of Collectors, One Lantern at a Time!

“A Human Being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, give orders, take orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook  a tasty meal, fight efficiently, die gallantly.  Specialization is for insects.”            - Lazarus Long


Quote


...
...
Welcome to the Coleman Collectors Forum, an international forum of Coleman enthusiast and collectors, as such people from all over the world come here to read about Coleman collecting, repair, and to meet and make friends. The pages contained here are intended for the use of amateur collectors and people interested in Coleman collecting, restoration and repair as a hobby. It goes without saying to refrain from political posts, personal attacks and inflammatory posts.

Please note, all postings are the personal opinions of the members posting, the owner, administrators and moderators of the forum do not warrant the accuracy of posted information or endorse the safety of such.