I have a 10+ year old ergo pump for my Omnifuel that developed a leak. Primus sent me a new pump free of charge when I asked about fixing the pump, good on them! However, I still wanted to fix the pump. This video shows a complete disassembly of the pump and a potential fix using epoxy: I personally didn't like the idea of using epoxy, so I bought some viton o-rings to seal between the metal shaft and plastic housing (size 1x14.5mm). I also replaced the o-ring on the pump valve connection. I used viton here too, size 1.5x5.5mm. I did not take a picture while doing this, but here is the entire replacement pic from the Primus site so you can see the o-ring I'm talking about: I put the pump back together and have burned to stove several times for about 10 minutes each and no leaks. I'd call it a success. I did have to order a load more o-rings than I'll ever use, so if anyone has a pump they want to try this on PM me. The viton that I used is only rated to -20degF, being that I live in Alaska I really wanted to get the low temp viton, but shipping from those vendors was just too much $$$ to justify.
Dear Mr. 907_Nick, I am really interested this job and very useful for Ergopump users. I've two pumps yet fortunately up to now they are okay. This leakage problem is very well known issue but Primus never does anything improvement... Also I saw few cases even in Korea where very few people use this stove...
@907_Nick Thanks for posting this. Thread I’ll save should the need arise to tackle the same job. John
Hello @907_Nick, I would be most interested in some of those extra o-rings you have for my ergo-pump. I'll send you a PM as well. Cheers
Many years later and still thank you for this useful post you took the time to share here. Second time this forum helps me to find o rings solutions for my stove. Hopefully, I will manage to find those orings sizes here in France. Knowing they must be petrol use certified...
