I have a primus71 given to me by an old friend.I am having a problem lighting it.I have half filled it with coleman fuel,put some metho in the bowl and lit it. It warms up I open the tap but I only get a small yellow flame at the jet.I have now pulled it apart,probably a mistake, there is a type of wick in the bowl which looks a bit raggard. Does anybody have any idea of what could be causing the problem. Also how do I get the wick back in the bowl. Can you buy new wicks? regards Malcolm
Hello Malcolm and welcome, First thing to check is the seal on the filler cap. If it is dry and stiff, it should be replaced. Second, clean the orifice of the jet with a pricker. If you don't have one, try a piece of wire from a steel wire brush - find one with thin enough wires. A ragged wick is not a problem, as long as it is not stiff with dried up residue, and does not break into small pieces. I usually put it back into the tank by simply pushing a bit at a time with a thin screwdriver. If you need a new wick, you can make one from a piece of pure cotton floor mop, and some copper or brass wire. Please post some photos of your stove. Yonadav
Thank you for the advice I'll give your instructions ago tomorrow. I'm hopeless with computors next time my daughter is down I'll ask her to put up a photo.
The replacement seal needs to be made of nitrile or viton rubber, ordinary rubber will be destroyed by the fuel in a week or so. Seals can be bought from people here or on eBay, but its easy to make your own if you have the right material.
Hello again, Malcolm, you obviously found your way here ok from u2b. As a stopgap you can cut a filler cap seal from a Fairy liquid bottle or plastic (HDPE) milk bottle. If you need to replace the wick check out this thread which will show you how. It's a different model of stove but the procedure is the same https://classiccampstoves.com/threads/92
My money is on a duff fuel cap seal. If you are not sure, prime but do not light, instead opening the fuel cap once the primer is COMPLETELY burned out. If you get a distinct hiss of escaping pressure, it may not be that, if you get a half hearted baby burp, it may be. Easiest thing is to get some O-rings from a hardware or car parts place, they are usually in assorted sizes in one packet and are dirt cheap. Dried out fuel cap seal is easily the single biggest knobbler of old stoves. Happily it's also the easiest fixed.
As I said I had pulled it apart, the wick has dried,I've cleaned te brass swaff from the wick and replaced it in the bowl,easier than I thought.Found a wire brush cut off a bristle and cleaned the jet,cleaned out the back of the jet as well. Reassembled the whole unit. Checked the filler cap and yes the rubber seemed hard.Given that the unit is probably 50 years old I guess thats to be expected. I removed the washer in bits,it fell apart as soon as I touched it with the screw driver. Went down to the local camping shop for a replacement, sorry you can't get parts for that anymore. I came home and tried to make one. Buggerised about for an hour and no good. So I shall have to look on ebay for one. Thank you all for your suggestions and advice. Regards Malcolm
Thank you for the lead kerophile. I purchased them this morning,my unit used the D washer. I note you are in Far North Scotland which part, we were over there a few years ago and went as far as Harris. We still have relitives in Glasgow and some friend in Frazer Borough.
The new washers arrived today, I have just fitted one and got the stove going. It doen't seem to roar as much as optimus stove I have that works on the same principal. I made a pricker out of a wire brush strand and a bit of a tin lid. But I don't believe it needs pricking. I guess it gets hot enough to cook on .
My daughter is coming over on the weekend ,I'll see if I can get her to load some photos of the 71 running.
I played around with it again tonight, I tipped out some of the fuel maybe 3/4 full now. It took a lot to get it going but once it started it seemed to run a lot better.
With all the self pressurized stoves you should open the filler cap briefly to equalize pressure before trying to run the stove. My first efforts with a Radius 42 were disappointing until I figured this out.
davecolter, I did that with out realising. I thought the new seal maybe leaking, so I took the cap off and put some oil in it to form an oil seal and tipped some of the fuel out at the same time. I refilled the warming reservoir with metho ,lit it and after it was very hot it finally started. It doesn't seem to matter if the tap is just open or fully open the flame seems the same. I guess it is working as good as it can.
Robbo When you upload pics before you close the box click on 'full size' and the pics will appear in the posting.
