After being very satisfied for almost 30 years with my Trangia (which is actually not even an original) I thought I should treat myself for my 40th birthday by branching out and explore other stoves a bit. The Manaslu 96 eventually caught my attention, and was just the right combination of beautiful, exotic (to me, because of the kerosene) and hard to get (from Japan, sold out in many shops). After the highly anticipated delivery the initial impression was good. It looks even nicer than on the pictures, maybe due to the fact that the brass is protected by a transparent varnish. Next I promptly tried it out with the classic "bring 1 L water to a rolling boil" test (unless further mentioned all tests were done with no lid on). The included manual gives an expected time of 4-6 minutes for 1L of water. And what should I say... I was a bit of a let down: The first test I did during lunch time with around 22C ambient temperature, almost no wind. But even after 20+ minutes the water wouldn't boil, and a thermometer test showed it just doesn't want to go beyond 77C water temperature. At first I blamed it on the pan I used (a stainless steel sauce pan), which differed from the pan I used on the trangia, which accomplished the task in 16:35 minutes, and my Primus Mimer gas canister stove (5:30 minutes). To be fair, the Trangia obviously has a slight advantage by having a wind shield.) So in the evening I repeated the test, now with 16C ambient temperature and a very light breeze. But still unable to get a hot cuppa from the Manaslu. After 25 minutes I showed mercy and decided to put a lid on the pan to help the poor little thing, an advantage that the other stoves did not have. But even with the lid on the temperature wouldn't creep beyond 80C. I also repeated the same test under these ambient conditions (without lid) on the Trangia and the Primus Mimer, which matched their previous times almost to the second. I can't see anything wrong with the Manaslu burning of the stove: It burns with a nice blue flame, and turns the burner a nice orange-red. Nonetheless I poked the jet with the included needles. I've also played with increasing the pressure hoping to get more power out of the burner, a task that made me realise why this stove design has not stood the test of time (I got very hot fingers). What I know now is that I rather stick to my Trangia(-knockoff). Although I am still puzzled with the poor performance of the Manaslu, because it sort of advertises itself as a stove ready for mountaineering and arctic expeditions. I'd rather not get caught in these situations with the Manaslu. Although it still looks beautiful.
@StefanD It doesn’t make sense. Your photo shows the Manaslu is functioning well and I’d expect it to get that quantity of water boiling vigorously in no time at all - well, five minutes at the most! As I write this I watched a Coleman 500A stove of 1955 vintage boil a couple of litres of water in five minutes or so, and that’s with the relatively huge distance a Coleman puts between the burner and pot base … … so no, I can’t make sense of the conundrum you’ve presented Stefan. John
Greetings, @StefanD, Welcome to CCS! I, too, am puzzled by your experience with the Manaslu 96, At first, I thought it might be because you didn't put a lid on the pot, as all stoves work better with lid in place. But, you covered that base. In my own experience, my Manaslu boils water very quickly, indeed, and I live at 5,000 feet of elevation. I've also boiled water on this stellar stove down in the desert, and at Sea Level. Performance has remained outstanding. So, I'm not sure why your own Manaslu is under-performing. Did you purchase it brand new, or used? If used, you might want to check the burner to make sure it's clear of all obstructions. But the photo you included looks pretty good. So, I am not sure it's the burner. Maybe a simple thing, like the pump leather bucket needs to be oiled? Again, hard to understand why you're not getting fantastic performance on your stove. What fuel are you using? I use K1 Water-white deodorized kerosene, and it offers a powerful flame, with no clogging. Just a thought.... I hope you can figure it out, as the Manaslu 96 is well worth owning, and using. Take care, and God Bless! Every Good Wish, Doc
There has to be a simple answer, but I don’t know what it could be. I’ve admired that model stove for years, but don’t have one. But with that burner, I’ve reckoned it’s more powerful than lipstick style 96s. Please keep us posted
@StefanD - Is the flame pure blue without heating anything? Is there any pulsing of the flame without heating anything? Pharael.
I have a question... When you run your trangia does it have a system you use that captures the heat like a shroud? The shroud captures a lot of the heat from trangia burners and the fuel itself rarely ever runs anything but blue but it's a system that (for lack of a better term) "Chernobyl's" itself... Getting a taller flame as the stove gets hotter it produces more heat... More heat... More flame... Etc until it runs out or is snuffed out. On the kero types it the effect is the same but reaches a balance where the jet is the regulator and the pressure behind it and will continue at a height of flame where the expansion of the kero going through the jet is the key. I would try it again...and put a foil windscreen around the stove and a lid on the pot. Again .. Just my thoughts...some may agree or disagree with me but it's my experience with these kero types.
I have struggled to get larger much volumes of water to boil on a similar sized stove but never had problems with a litre. A tall folding windshield similar to the one that is in @presscall 's picture is a very wise investment. Regards John
Here's a photo of the Manaslu in use in 2016, in the Glacier Peak wilderness just outside Mt. Rainier Nat'l Park. The caption on the trip report says it burned hot and blue and 'boiled the side dish nicely'. I always use foil wrapped around the pot supports when using the three-legged brassies outdoors. The faintest breeze impacts performance.
So I did another test run today and did some more measurements. Test conditions were similar to previous tests (trangia pan, no lid, 1L (or more precisely 1kg) water). Ambient temperature today was 23C. I let the stove run for 25 minutes and measured the water temperature every minute. I also gave the pump a stroke or two every minute to keep the pressure up. I also weighed the stove before and after the test to determine how much fuel is used. The result is quite interesting: It burned 26g of kerosene in 25 minutes which means the theoretical maximum power the stove produced is 745W, which, even if any losses are neglected, wouldn't be enough to boil the water in the stated 4-6 minutes. The manual doesn't give a figure for the output power, but it says the stove should run about 1 hour and 15 minutes on 0.2L of fuel, based on that the estimated output should be about 1.53 kW. So I'm only getting about half the output power of what it should be! (Or if taking a "the glass is half-full" perspective: double the runtime ) I found this other thread of a user with a similar problem, and he found metal shavings in his burner. Maybe mine has a similar issue, that obstructs the fuel flow to half of what it should be? I just wouldn't know how to get the jet out, as it is quite inaccessible with tools between the generator tubes. The other option would be to unscrew at the bottom of the burner where the ignition/preheat cup is. But I'm not sure whether it uses reusable gaskets or single-use (lead?) gaskets there. Also I'm not sure how far I want to go with repair attempts. A return would be difficult given that I ordered it from some Japanese shop via a mail forwarding service, but maybe there is still some chance to get it "officially" repaired or returned.
To answer some of the questions From @Doc Mark: > Did you purchase it brand new, or used? I bought it new from SLOPERS/アウトドアソリューション powered by BASE > [...] the pump leather bucket needs to be oiled? AFAIK the pump in the manaslu uses an O-ring, not a leather cup. That said, to me it feels that the pump is building up pressure quite well. But I might give that a try tomorrow. > What fuel are you using? I'm using "Diggers Low Odour Kerosene" as fuel, which works well in my Petromax HK500 lantern. From @Pharael > Is the flame pure blue without heating anything? Yes without a pot on it pure blue. > Is there any pulsing of the flame without heating anything? Most of the time not. I paid a bit more attention during my latest test today, and sometimes it "purrs" a bit, but not for long, maybe 10 seconds. From @Remus1956 > When you run your trangia does it have a system you use that captures the heat like a shroud? Yes, I used the trangia in its normal wind shield set up. That indeed, as mentioned, gives it a little bit of an advantage as neither the Manaslu nor the Primus were run with a wind shield that could funnel the heat. But while not ideal, these were not harsh conditions on my patio, and this was not a problem for the Primus.
Question to the fellow Manaslu 96 owners: How many pump strokes do you give it at the start? And how often do you add pressure while the stove runs?
With an empty stove and the filler cap off. Place your thumb over it and seal it. With the other pump the pump and you should feel the pressure build up in the tank. About when it is hard to keep your thumb sealing is probably a bit full snot pressure. How many pumps? It’s about the volume of air in the tank that has to be pressurised by the pump. The pump volume and also the seal of the pump washer, plus the pressure needed to open non return valve and let the air in. Think pumping up a bicycle tyre. With the empty tank you may feel and hear the nrv pop open. This is not a bad thing, it just means they is a good seal and pressure in the spring that keeps it closed and safe. The valve may be a bit sticky. In that case it will go creak,shutter,creak,shutter shutter. You will feel it grab and release. It needs to lube up a little and seat and wear in properly. Lubing the pump leather is never wrong. Motor oil , wife’s 3in one singer sowing machine oil. Virgins of olive in a pinch.Kero its self. Any better than none, some better than others. Nothing that can’t be fixed by this mob. please report back with findings.
Is your pressure release/vent valve closing properly and tank seal? You could test it by a drop or two of soapy water. Seams your stuck on low pressure simmer/self generating mode. Should be burning 2 1/2 to 4 ml per minute. That low odor stuff burns a bit cool if I remember. Try some good old nasty blue stuff. I think they take the starch out of its undies a bit, but not …..that bad. So the kero should be good. Your only on 1/2 power if even that! Be something simple
@StefanD how full are you filling the tank? the ideal seems to be around 3/4 full in my experience. The air that you pump in will expand as the heat that you have noticed coming down from above completes a feedback loop that maintains the burn without need to keep pumping. Have you got a fine wire pricker that can clean out the hole in the jet? Regards John
Hello StephanD I don’t own a Manaslu stove, but I do have several others in the same class that are almost identical in design: the Juwel No. 21, the Primus No. 210 and the Radius No. 21. Typical boiling times (indoors) for 1 litre of water with these are 6½ to 8 minutes. Each uses 18 to 20g of paraffin. I’ve taken hundreds of such measurements, as I boil a litre of tea every day and record the time and fuel consumption using scales. Your method of measuring fuel consumption with scales is correct. If 25g of fuel is consumed in 25 minutes, that is undoubtedly too little. With a new stove, there are really only two reasons for this: a loss of pressure due to a leak or a blockage in the burner or (more likely) in the nozzle. Check for leaks: place a tiny piece of candle wax on the nozzle and heat it with a lighter. The wax will melt and flow into the nozzle opening. Let it cool down. The nozzle is now sealed. You can now inflate the empty tank and submerge the stove in water. Check for air bubbles escaping from any of the following: the filling port, the bleed screw, the burner connection, the tank connection, or the valve in the pump. Don’t worry – the wax will evaporate without a trace the next time you preheat the burner. If there are no leaks, you’ll need to unscrew the nozzle, check it and blow through the burner. For a roarer burner, you’ll need a knuckle jet removal key. The cooking times specified by manufacturers are very theoretical figures. You measure the fuel consumption and calculate the heat output using the calorific value. In practice, the cooking time depends heavily on the shape, position and size of the cooking pot, and of course, a windscreen must always be in place. Good luck Radler
