Hullo. Just wondering if there is supposed to be a lead washer on the check valve, to seal it against the base, at the bottom of the pump tube ? The check valve on my C-38 Coleman 500 stove is leaking, and I don't have any miracle carburettor cleaner. Is there anything else I can use, please ? The threaded, pointed valve is o.k., works fine. Belt and Braces. I'm used to seeing such washers on many other lanterns. Yes, I will have to get a new one, just to have a spare. Meantime perhaps this old one can be made to behave. My poor little Clisby compresssor has expired on me, so the only air blast I can manage is from a bike pump, and is insufficient to clear blockages in tubes.
Can't comment on the washer. The other common recommended check valve cleaner is lacquer thinner. Can't hurt to try other thinners such as paint thinner or acetone. Thinners will dissolve the crud. A vinegar bath is more of a metal cleaner and it does not look like rust problems from the pictures. Can try sticking a tooth pick in hole might feel the spring action. Daryl
No, not on a 500 Speedmaster. Some modern Coleman check valve installations have a thin O-ring. You say it’s leaking. So pressurising the tank results in fuel getting through the valve - ball in the valve stuck open. Empty tank of fuel. Prop up the stove with the pump tube vertical, opening uppermost and pump rod and pump cap removed then partially fill the pump tube with a mixture of kerosene and auto gear box or power steering pump oil. Let it soak for a day or two, topping up the fluid as necessary then insert the pump and attempt to force the fluid through the valve. Repeat process if necessary after you’ve tested the check valve is airtight. John
Thank you, Daryl. Thank you, John. I will follow your suggestions. One of the reasons I asked about a washer is that the thread on the check valve is undercut, (or what do you call it - runout), but the shoulder of the valve is not very wide as compared to the bigger, spring-loaded, two-piece valves which are encountered elsewhere. So there's not much room to seal face-to-face. Wouldn't it be handy if the check valve was made in two pieces so that one could dismantle, clean it, and maybe replace the 1/8" steel ball ?
I obtained check valve replacements for a Coleman 505A and 400 stoves (from Old Coleman Parts). Both were supplied with a small "O" ring. It fits snugly under the collar of the valve. They look exactly the same valve as in the photos that you posted. Cheers Simon Foxxx
500 did not have any sort of sealing washer originally. You say it leaks....it is not supposed to be a good seal like a NRV with a pip, and it WILL always leak a bit, that is why you have the air screw (the long shaft w threads) to screw down and create a seal. If the little ball is loose in there, that is the only thing that it needs to work. It should not have fuel at check valve. THere is a snorkel/tube that extends from end of pump tube up to top of tank so only air is behind check valve, unless you over fill or tip tank.
Thank you, Simon. That was my worry - the gap between the end of the thread and the face of the shoulder of the check valve. I'll buy one or two of the ones you mention in the next order. I reckon they wouldn't do any harm in the 500 stove. Aha ! Thank you, too, Maji. Now I understand. Do all Coleman stoves / lanterns have that snorkel tube ? I'm so used to NRV 's with a spring-loaded pip, that seal completely, but can fill the pump tube with fuel when they leak. Surprising - I've yet to see a damaged taper on a Coleman air screw, though one of my lanterns has a very tight thread. All the above advice much appreciated. Cheers. Paul.
Some of the oldest Coleman products may not have a snorkel but everything from the 1930s on does. It is a very simple design feature that prevents fuel from coming back into pump tube. A feature many other GPAs could benefit from.
Even my Coleman stoves from the teens have such a device. @Paul Aslanides Coleman did good with that air screw that doesn't ride up and down when you pump. AGM has the screw right on end of pump shaft so it beats it's threads with every stroke if you bottom it out. Lots of AGM's with buggered threads that don't seal well.
Greetings, this is my first post. I have a Coleman 550-499 stove. I opened the pump, pumped it a handful of times then closed it. I fired up the stove and then turned it off. When I went to work the pump again, it will not move. I tried the same routine, i.e., turn the pump one turn or so to open it, but I can't pull the pump stem up now. It's as if the valve at the bottom is stuck or something. I can completely unscrew the stem and remove it. But if screwed to the valve at the bottom it won't move. Any ideas what went wrong and how to fix it? Thank you for any assistance you can provide.
