Gooday, I have not removed a Coleman 237 NRV previously and am ready to put one back into a Canadian first quarter of 1938 unit. Schematics don't show if a lead washer or O-ring go on it. Couldn't see one when I removed it. Old Coleman parts show one without an O-ring but many other Coleman NRVs there, have them. My gut feeling is I like them to seal well. Hoping someone knows; thanks
Couldn't wait for a response but probably these 237 NRVs are not normally in need of attention. Mine was stuck and needed a soak in carburettor cleaner overnight. 1. No washers sighted when NRV removed 2. Some Coleman lantern replacement NRVs show an O-ring 3. The Coleman 237 NRV for sale does NOT show an O-ring 4. Probably never had or needed a washer seal originally. 5. I've added one anyway as I worked out it would fit. 6. I used an 8 mm ID and 1.75 mm thickness O-ring 7. Worked well and lantern tested fine; no leaks. O-ring on NRV ready for installation using special tool View down pump tube after NRV seated Close-up with measurements Flame overall (Note: Temporary Non-original pre-heater cup) Flame at burner cap
I guess you all Ready figured out that there is no need for an oring or washer. Why Coleman sold some with an oring is unknown.
I've removed dozens of Coleman check valves (frequent and heavy Coleman fetters know that nrv with the rubber pips were were only found on certain models in the 1930s) and have never seen an o-ring on any of them. Do you have pics of that lantern? I've never seen a Canadian 237 that old.
The 237s are ballers. You’re going to love that lantern. One of my top favorite Colemans. Use a big #11 mantle, sock shaped, not globular like Petromax. Ulf.
Thanks @Phredd and @newfie for replying and clarifying no washers needed on the NRV where it seats. Thanks @Andrew T for mentioning the other early 237's in the Gallery. Yes, @Ulf I appreciate your advice on the mantle and the overall lantern quality. I tend to agree with you. Interestingly though is that the O-ring fitted remarkably well and tightened easily. I suspect it will be easier to remove in future too. Iain
Just to be a bit pendantic, the Coleman valve isn't a NRV (non-return valve). A NRV makes a air/fluid tight seal and allows no air or fuel to pass back into the pump. The Coleman check valve (CV) is not meant to be an air tight seal, it only retards air flow back into the pump enough to let you pressurize the device. If you pressurize the device without an air stem, then add some liquid to the pump tube you will always see some small amount of bubbles from the CV. The air stem that screws into CV is the air tight seal. The O ring isn't required, the CV should seat without anything between it and the pump tube. IF you plan on having more then one Coleman GPA buy the CV removal tool shown in the first picture of this thread. It makes removal of the CV so easy that it becomes part of any major service of the device. The first time you mess up a CV using a large screwdriver or other home made tool you'll wish you had bought the right one.
Reese has it exactly right ... and not pedantic at all ... it's a very important distinction between NRV and CV. That Coleman-style extraction tool is money in the bank. That said, having an equal love for Swedish and German lanterns as for Colemans ... the fact that Coleman used a check valve instead of an NRV makes Colemans far less likely to require drilling out a stubborn or stripped NRV. The little check ball inside will get gummed up, but half-filling the pump tube with Kroil or carb cleaner overnight will *almost* always free it. If it rattles, 9 times out of 10 it will seal just fine. Not so with the Brits, Swedes, and Germans, whose NRVs have those maddening little rubber/cork pips in them and will almost always require replacement after a number of years. I have had to drill out quite a few Swedish style NRVs and, I think, only one Coleman CV as a result. And while one can fashion a decent removal tool for the Swedish style NRVs, it lacks the key component of the Coleman removal tool -- the threaded rod that holds the splines tight into the very bottom of the CV's slot. Anyhow each type has its advantages but I will say the Coleman CV has the advantage of simplicity. I have 100 year old Colemans that required only a soak in solvent to free the CV and which will then work perfectly well without requiring the sometimes fraught job of removal. By contrast, any NRV more than 50 years old (and often far less) would be a kind of miracle if it didn't require pip replacement -- and will need to be removed. The above is mainly for newbies. I recognize most of you fellows know all this, but when I was starting out I sure didn't! Ulf.
I stand reminded in respect of later model Coleman check valves. Yes, for over a decade on CPL I have usually used the term check valve for Coleman and non-Coleman lanterns alike. However, notwithstanding the accuracy of the terms which I do fully appreciate, I sometimes succumb to common country parlance based differences of USA - Checkvalve and British - NRV. So have many CPL users before me which is why they often bracket the other term. What I also find interesting though is the issue of why check valves need a special tool to get them out after many years? Why, have I wrenched pump tubes out of founts at times whilst attempting to get check valves out? Why do they seal and seat, brass-on-brass, or brass-on-lead so well? I did see the reason once but have long forgotten it. I am just a little suspicious and perchance, hopeful, that in the case of my extra O-ring, which just happens to work in this instance and probably wouldn't and shouldn't for most check valves , it will possibly make it a lot easier to extract next time around. Yours in lanterns
