Hi fellow liquid fuel addics. I'm fetting a Primus Himalaya Varifuel, first series... I guess (squared aluminium pump head with incorporated valve). My first pressure test results in fuel coming up from pump tube. As always, my archenemy... the infamous Non-Return Valve coming from my worst nightmares. Does anybody know the exact dimensions of the itty bitty "O"ring that acts as seal? Thanks in advance. Best regards. Héctor.
@Celsius233 I removed the black o-ring and it measured .210" OD, .073" ID, and .068" thick. A new blue replacement o-ring measured .210" OD, .070" ID, and .065" thick. If you are able to find Primus P-721460 it has the part you need and more. Hope this helps. Mike
Thank you very much @HunterStovie After convertion (I'm into metric religion), my O'ring have same dimentions. It's not hardened, quite elastic and have a shinny surface. I guess must try to clean thoroughfuly the mushroom and valve surface to ensure a good sealing. I was confused because this picture I found into the user's manual have a ball instead O'ring/mushroom pip. Let's try an see if I can get the beast roaring. Thanks a lot! Héctor.
I've found the guilty while cleaning the valve... I guess. The O'ring that seals the body of NRV against the pump tube was hardened. The valve was barely loose, enough to let the fuel leak.
Hello maybe this link would be helpful http://www.ir-dichtungstechnik.de/shop1/index.php?cPath=262_265 Best wishes Markus(RJ)
Thanks for posting the pic of the plastic nrv body out of the pump tube. I did not know this was a serviceable part or that there was an o-ring on it. I thought those dimples were to permanently peen the plastic piece in the tube. I messed around with my parts pump and figured out how it came out. This was also a real good time to clean the gunk and old pump cup lube residue out of the bottom of the pump tube. I used a 3mm diameter round screwdriver shaft to twist the housing out of the pump tube. Since the plastic housing is not directional, you can twist it on as seen in the above pic, in a counterclockwise direction. Or you can use the flat side of the screwdriver head to twist it. The 3mm rod was a little to big to fit in the slot, and I did not want to force or break it. A 2.5mm or 2mm shaft would probably be fine. A small amount of lube on the o-ring is a good idea too. Regarding the o-ring and/or ball: I feel like the o-ring on that brass piece is a poor design. On a couple of my user pumps I have replaced the brass piece and o-ring with balls out MSR service kits. On one pump I have the "updated" MSR ball (approximate ball head diameter 5.4mm) and MSR spring (slightly expanded to match the length of the Primus spring. This is my go-to pump, and do not have any problems with leaks. On another pump, which I have used a lot, I have the earlier style MSR ball (approximate diamter 6.3mm) and original Primus spring. Again, no problems with leaks.
@Russenjesus Thanks for the reference table... I usualy go to my O'ring dealer and try them before buying. @Hazet thanks to you for your pictures. I used a small parrot nose pliers to turn de valve. I didn't dare to force the hollow tube of the valve housing like you did. I haven't any plastic or stainless steel ball of suitable size so... considering that the original O'ring pip is in good shape I´m gonna reuse it whith the cleaned bronze mushroom thing. Now... I got my new viton O'ring ready to fix de NRV to the pump tube. Did you use any sealer/glue to fix the NRV to the tube or just trust in the loosed dimples in the tube over the plastic body and the O'ring's friction? Regards. Héctor.
@Celsius233 , @Hazet On the new ergo pumps that o-ring is blue. I have taken apart a few ergo pumps and have not seen the failure you experienced. As for using the MSR parts I've not felt the need to try a work around because primus parts are available, and they've given me no trouble. I've also never found a need to use any sealer on that part when reassembling the pump. I can't wait to see the flame shots once you get your stove up and running again. Mike
@HunterStovie @Russenjesus @Hazet Burn, baby burn! Burn,baby burn! This is my first modern split stove. I haven't previous experience with aluminium/plastic stoves. You were very helpful. Thanks a lot guys! Best regards. Héctor. PS: Please, forget the dirty floor. Was a rainy week here.
BTW... Aluminium pumps and plastic NRVs, all holded and sealed by viton O'rings. What's next? Porn through computers?
With the new software, you just use an app on your smart phone to send a message to your food packet telling it to cook itself. ....Arch
@ArchMc I got one app, WhatsApp and my wife. I send the message: "what's for dinner, darling?" and she responds "Whatever you bring, alpha male, and cook by yourself". I think is still not working fine, needs some debugging.
