Today's little job is to get the NRV in my Monitor stove to seal properly. I removed it, stripped and cleaned it, made and fitted a new nitrile pip and new lead washer. So you can imagine my disappointment when I lit the stove and found it leaking badly when pressure builds up - and leaking a lot of paraffin not just slowly pushing the pump rod back out. My guess was the spring, which looked fine and was 10mm long, may have lost tension so looked through a box of old pens for a replacement. Unfortunately, the diameters of the only springs I could find were either too small for the pip carrier or too large for the valve body. I've just stretched the spring a little so will try that later but am I on the right track? Cheers, John
There is exeter_yaks freshly dephotobucketed tutorial. Way advanced for my level of skill & tools but the last post shows a quick & easy method. https://classiccampstoves.com/threads/5646
An excellent tutorial and an inspiration. In these days of powerful cordless drills I now see a use for the old hand drill I found while clearing out my father's shed on Sunday. Re my NRV: Stretching the spring worked I lit the stove and let it run for several minutes and, even with the pump removed, not a drop leaked. I don't think stretching the spring is a long-term solution but was sufficient to confirm my suspicions so will explore making my own new springs. Cheers, John
Often in replacing an NRV pip we neglect to clean the sealing surface. It has been my experience that a pencil eraser given a few twirls on the nipple of the NRV nipple will sufice in getting the knife edge clean enough to seal a new pip. lance
