Hi All, I shared my cook box designed around my venerable SVEA 123R to y'all a few years back: SVEA 123R safety Dinghy Cruising? In the past year I have had intermittent problems with the stove, especially a lack of power compared to what I am used to. I bought a rebuild kit and broke the stove down, replaced fill gasket, stem packing and wick but performance continues to be erratic. Some times I get a nice, powerful blue flame like I am used to, other times i get a lot of pulsing and yellow/orange tipped flames, other times it starts out strong and then gets progressively weaker no matter how long I let it run it never seems to get up to speed, or it just slowly stops running. Everything seems to be dogged down tight and if I leave it overnight and come back it may well fire up and run like a champ the next time I start it. SO frustrated that I bought a modern canister gas stove as I was sick of being unable to make supper or morning coffee, but I miss the compact setup the 123R afforded me. There seems to be no rhyme nor reason for it but I am sure one of you all may have some insights, would love to go back to the 123R if I could rely on it. I welcome your comments and suggestions!
@JW Arthur The symptoms resemble those that exasperated the original owner of THIS Svea 123R. The burner stem-to-tank taper-threaded joint was not airtight and erratically leaked pressure from the tank. It was a modern era product and the threads were poorly formed, such that they wouldn’t seal when super tight. A smear of thread sealer (I used a Loctite product) resolved it. I daresay graphite grease would work too. John
2 things come to mind of what your problem might be. 1 maybe the safety release valve in the fill cap. The rubber inside may have hardened up and causing some problems. You may rule that out by heating the stove up and put the tank underwater and see if you can spot bubbles leaving the center hole in the filler cap. 2 might be the wick inside the stove, that carries the fuel from the tank to the burner and might be worn/scorched. The only way to check that is to unscrew the burner from the tank.
THX John< I read that thread while I was poking around to find some answers, Loctite thread sealer? I have Loctite red and blue thread lockers but I am guessing something else? noticed a tiny white line at the tank to burner stem junction in one of your pics, can that be Teflon plumbers tape? THX, Jim
I used blue Loctite Jim. The white line is the result of the effect of stove heat on it, which hasn’t adversely affected its sealing properties.
did a dunk test, no bubbles, looked very carefully at stem to tank and filler cap. topped of fuel, double primed and fired it up and got perfect blue flames and roaring fire, energy level dropped off a bit and started pulsing, put pan of water over top which came to boil in good time, backed off flame to what I would call a simmer for a few minutes and then back to full throttle and got to back to high heat solid blue flames. starting to wonder if the aluminum plate it sits into is acting as a heat sink, and that needs to heat up enough to stop drawing heat off from the tank which prevent it from getting the fuel to full pressure?
JW, This likely isn't the answer, but...is your tank full right up to the top? Always run my kero tanks somewhat less than full, 'cause liquid doesn't compress. Always did the same with the 123R, just because...of course my thinking may be twisted. Doubt the aluminium plate is pulling enough heat from the stove to retard operation once it's cooking along. Oh yes...your portable SVEA123R dinghy galley is truly a work of functional art! Lovely little vessel too!
The tanks should be flat when filled. That always leaves an adequate air space. I know its easier especially with the small stoves to tilt them. I always tip it back a little past flat pouring any overflow back into the fuel bottle
Gentleman, still trying to solve this stove issue, hopefully before the spring sailing season starts. I followed all of the advice above eg dunk rest; loctite on threads at tank etc. cannot figure it out. Very frustrating . Wick is new, packing at valve is new. Here is what is happening: I prime with white gas in the depression around the stem, when primer burns out I open valve and ignite burner, I get a solid roaring blue flame that burns strong for a minute or two and then slowly peters out, I just don’t get it, any help most gratefully accepted, thanks!
You are losing pressure somewhere. One more test. In the dunk test. Let it sit in the hot water a bit to build up the pressure. Burner bell off. Valve closed. No bubbles. Then.... Open valve under water and see if a steady stream of bubbles come from jet. And notice if bubbles stop, or if bubbles are coming from somewhere other than the jet. Maybe you have a crack. Crack can sometimes only show when metal is hot.
Interesting, just trying your test. Steady stream of bubble / jet of fuel when valve is opened, when valve closed bubbles leaking from jet. No other sign of bubbles elsewhere. Will tighten jet, but kind of doubt that could be the issue…. iCloud Photos - Apple iCloud
Remove jet. Turn key/valve. Pricker will rise. Put pencil eraser onto pricker (do not bend it). Remove pricker when released by rack. Close valve. Replace jet. Test. No damage. It will operate fine without it. Might need manual pricking occasionally. Replacement is a little more complicated, but easy.
You said that the aluminum base plate might be acting like a heat sink, have you run it with out it? Try when the stove is running and is loosing pressure use the soapy water trick. Fill the priming dent and spray around the cap and spinal and everywhere else and look for bubbles. Your leaking somewhere it might not show up until it's good and hot.
Everytime? My only thought now is to open the valve slowly after priming. Open just enough to get a flame and increase slowly. A small hand torch heating the tank increases pressure. I try that then see if the pressure holds. (Not too much)
Since the pricker has been mentioned here, I experienced some time ago that my Svea 123R wouldn't function properly. And discovered in the end that the pricker was broken. It didn't protrude out of the nozzle when the valve handle was turned all the way to the left. So I ordered a couple of new prickers ( one in spare) and installed one of them, and voila, the problem was solved.
