Would any kind soul be prepared to lend me their Coleman NRV removal tool? I've rebuilt a 220 but the NRV is stuck wide open! I wouldn't use one enough to justify buying one and I don't think I could make one very successfully without a lathe! If you're in the highlands of Scotland so much the better.
Hey Colin, you can borrow mine, it’s a beauty. We’ll have to bring it over though. Kaye and I’ll pack a cut lunch coz we live just down the road in Queensland Australia. Cheers Pete
Colin Before you take the check valve out of the bottom of the pump tube, have you let the pump tube soak in thinners, then penetrating oil, and then given the ball in the valve a bit of a poke with thin stiff wire? I’ve got the tool, but I’ve only needed to take the check valve out of Colemans two times. Cheers Tony
I've soaked the tube in an acetone/transmission fluid mix and poked around with a bit of wire but the ball bearing hasn't moved yet. The NRV is stuck in the open position so I might have to fill the tank with the cleaning fluid and leave it for a day or two. Meanwhile I'm planning on making my own check valve tool having seen one made on YouTube. I'm currently having trouble finding thick wall tube, nominally 1/2 inch o/d with a wall thickness of 1/8 inch. If anyone knows where I can buy some, or a close metric equivalent I'd be grateful. The 220 is complete and ready to go apart from the NRV!
Colin, Details are here as a guide to make one. Coleman check valve remover Notes: ¼’’ x 32 TPI is NEF (National Extra Fine) thread. It has been recommended sleeving with 20mm PVC pipe to prevent scratching the tube. Here is mine that I made loosely following those instructions.
@ColinG I'd certainly loan you mine, but for the postage you could buy your own. The one Martin shows is a bit more complicated than the ones fabricated here, which are just the barrel, rod and nut the barrel being machined out of bar stock. It looks like it should work just fine though as the biggest requirement is a way to keep the blade of the tool firmly engaged in the slot of the check valve. If you do more than a couple of Colemans the tool is worth the expense. With the tool check valve removal is so quick and easy that it becomes a routine part of every lantern overhaul. These are what I've reworked in the past six weeks or so and I pulled the CV on everyone except the Akron. Be aware that there are two sizes of hole in the check valves, the smaller being used on the newer lanterns. I don't know when the change came but I'm thinking it was in the 80s. External dimensions on the CVs are the same and as far as I know they are interchangeable as long as you have the proper air stem to go with it. The military lanterns take a different CV but the tool works for them as well using the large rod. Some CVs had a rubber gasket, some didn't but it wasn't necessary. Here are the two air stem sizes. Looks like some bright boy figured they could save $.002 per by eliminating the separate threaded tip. Probably got himself a nice bonus for the idea. Best of luck.
Thanks guys, I've bought myself a 1/4 inch 32 tpi die and a few bits and pieces to make myself a check valve tool. When I've finished it I'll post about it.
- Ah this may explain why new check valves always come with a replacement stem. New ones also come with a rubber o ring but following advice here I did not use it, and pressure is held. It might be that older lanterns need it due to a different profile around the hole in the bottom of the tube ?
The older CVs had no gasket. The CVs are interchangeable regardless of age of the lantern back to the late 1930s depending on model. Back beyond that is a different story.
Interesting and I have more reason to believe anyone here than anywhere else - so why do the new replacement valves come with an O ring I wonder ?
Lower manufacturing cost and potential future sales I imagine but I may be wrong. As I understand it, modern Coleman lanterns use a Schrader valve arrangement and while this is fine on a bicycle tyre it's not safe on a lantern - in my opinion. When o rings reach the end of their life their failure will allow volatile Coleman fuel into the pump, which obviously isn't good and could end in a fireball! It's best to change the o rings at regular intervals to avoid a potential disaster.
Hi Colin - this is on the NRV (check valve) not the schrader valve fitted I think from the 275 (1976 ?) up to todays' Coleman lanterns. They are OK as long as you replace them with fuel resistant versions of the schrader valve. You cannot change the seals on a schrader valve (Well you probably could if you were really determined but....) Now if you would like a few of those just PM me cheer Chris
Aha, thanks for the info... I'm not as up to speed on Coleman check valves as I should be! But... my home made check tool is coming on, I'm just waiting for some specific nuts. This is where I've got to do far... To explain what's going on, I had the threaded brass rod already so I decided to use it. The long threaded section is 1/4 BSF and the shorter section is Coleman specific, 1/4 inch 32tpi for the check valve thread. It's all a bit if a bodge but it'll work. The stainless tube didn't have a thick enough wall so I used some brass tubing as a bush top and bottom. It's an interference fit so it should be ok - only time will tell. All I need now is a 1/4 inch BSF nut to lock everything solid and to grind flats on the tube so I can fit a spanner to undo the check valve.
Hello crap that was corroded in there extremely tightly! Also, I'd already noticed some damage to the brass slot but it was much worse than I'd realised... and although my tool 'worked' it suffered irrevocable damage! I feared that the tube wasn't really up to the job and it wasn't... oh well, it did what I asked of it but it paid the price! I have a replacement thank goodness but first I'll be ordering some 12mm of tube with a wall thickness of 3mm that should work much better! So... success of a sort but without new thick wall tube I won't be installing the replacement check valve ant time soon, and certainly not with the current tool!
Ouch ! well at least you have a way forward now - you know I have always gotten away with using a thumping great big screwdriver. Maybe I have just been lucky !
@ColinG the method and process was correct it’s just the materials that need refinement and it looks like you have that sorted. Cheers Pete
@ColinG I had the same problem with tools purchased from Ebay. Steel not strong enough, it broke twice.
@ColinG Sorry to hear that .. You could try mild steel then case harden using something similar to Kasenit ? You probably know already there are types of stainless that you can harden? There are so many grades of stainless…
Yeah, basically I was trying to work with substandard materials. I knew the tube might not be up to the job but I didn't realise how tight the Coleman check valves are screwed in, or that this one was also corroded in position! Anyway, I've ordered a length of thick walled steel tube: 12mm o/d, 3mm wall thickness with a 6mm i/d hole. I think it should work way better.
@ColinG The tool I use is made from bar stock and has flats milled on the upper end for a 5/8" wrench (spanner). The proper way to use it, according to the original maker is to screw the center rod into the CV, slide on the tube piece, snug up the nut on the center rod then fit a spanner to the flats and with a suitable mallet, give the free end of the spanner a sharp whack. This is opposed to just applying steady increasing pressure to the spanner. I've found that the quick hammer blow is much more successful and easier to break the CV free than trying to torque it free with steady pressure. I replaced the nut on the rod with a wing nut, faster, easier. @Fireexit1 You've been lucky. Screwdrivers usually ride up out of the slot and you end up with a CV that looks like the one Colin took out. Colin, if you want a newish CV and don't mind the wait for it to get there, PM me your address and I'll send you one. What shape is your air stem in? Is there a groove around it. If the groove isn't too deep you can polish it out, otherwise it's a lathe job. I went through my collection of worn air stems last year and recut the tapers on 8-10 so I've got a pile of CVs and stem, glad to send you what you need.
The end of the centre rod screws into the center of the check valve and when you tighten up the end screw, the outer tube that fits into the slot can't jump out and chew up the brass. On mine, someone had obviously tried removing the CV with a screwdriver and really messed it up. Combined with that, the tank had been left outside and the CV was partially corroded into the end of the pump tube. Frankly I think I'm lucky to have got it out at all! Although my home made tool didn't survive, it worked just well enough and the central rod can still be used when I get the thick wall steel tube I've ordered.
Mark 2 The new steel tube arrived. I went for cold drawn seemless 12mm O/D, 3mm wall thickness leaving a 6mm I/D. I reamed the hole to out 1/4 inch to take the central rod and then set about cutting and filing the cross piece and the two flats that allow the tool to be tightened or undone. I plan to case harden the main body of the tool to increase it's strength. That way the 'blades' or 'paddles' or whatever you call them shouldn't get mangled! It would have been a lot easier with a lathe and a milling machine but I've only got a pillar drill, a grinder and hand tools.
Well done Colin. I did in fact manage to break one of the blades on my NRV remover so your hardening plan sounds good.
Looks good A sleeve of PVC at the top of the pump tube will help keep the tool aligned with the valve. Reducing stress on the teeth and protecting the pump tube.
Excellent idea. I was thinking of using an O ring to keep things centred but the gap may be too large so I'll look for some plastic tubing instead.
