Nitrile balls A 3/16" Diameter made a great new seal for my Veritas pump NRV. I bought mine from here: https://maccmodels.co.uk/live-steam...16dia-nitrile-balls-pack-of-5-live-steam.html Nitrile is recommended for petroleum fuels I believe I use this supplier frequently and recommend them
@David What an excellent idea! Thank you Dave. Common practice in the pumps of modern ‘bottle’ stoves but I’d never thought of installing one in a ‘classic’ stove NRV. A great example of the benefit of the diversity of CCS member interests as well as stoves. John
I thought that as well John. Sadly the model shop in town doesn`t do them so I`ll be ordering a goodly stock asap. The ball must give a more reliable seal than a flat surface.
I've just read Ross' store's write-up on nitrile vs viton. These balls may not last. After about a week of no use I thought I detected some stickiness in the NRV - remaining closed again. I'll keep my eye on it.
Thanks @David. We're having a good dry autumn so the allotment has eaten into fettling opportunities. We had a dreadful spring and with heavy clay soil you have to get a fork in the ground while you get a chance.
I've just had to remove my Primus 41 pump non return valve as it was stuck closed, it had my 3/16" Nitrile ball mod in it! I hadn't fired-up the stove since 2020, there was hardly any fuel in it. I made a new extraction tool to securely grasp the flats of the nrv. First I tried 4.5mm, then 4.8 and a little engagement was felt, then finally 5mm. Once retrieved, the flats measured at just under 5mm AF. With the NRV in my hand the blunt end of a 2mm drill fed in from the front was able to free the valve. The NRV's on my Optimus 182 are stuck too!
