primus omnifuel overheating and going out

12:30 a.m. on March 4, 2013 (EST)
0 reviewer rep
7 forum posts

can anyone help? we have been cycle touring for 9 months and have been using our primus omnifuel several times a day without a single problem, we use a muter with it which has made it very quiet easy to adjust and uses less fuel, all was well until we crossed from egypt into Sudan where we refilled our bottles. since then the fuel seems oiler. it starts ok then the blue flame turns more yellow then the muter glows orange and stops burning the fuel. we returned to the flame speader and find the flame goes out with the slightest breeze and has less heat. we met a polish guy who had a msr stove and his was playing up and sonot shore if its the same problem.

we have striped the stove tried different jets changed the filters but not o rings. we have a maintance kit but are baffled why the muter glows orange, is it air getting in or something else? we really want to solve this as it really is a great stove. any comments would be well received

3:58 p.m. on March 4, 2013 (EST)
TOP 10 REVIEWER REVIEW CORPS
2,430 reviewer rep
5,314 forum posts

Several things going on here. First, you might read my review of the QuietStove cap, which is what you are calling a muter, I believe. Second, I assume that when you mention "refilled our bottles", you are referring to the bottles for liquid fuels, such as white gas (petrol, benzin, unleaded autogas), kerosene, or diesel. When you say the fuel seems "oilier", it sounds like you might be using kerosene or diesel rather than "white gas" (which is naptha). The different fuels have different names in different countries, sometimes using the same name for a different fuel than some other countries. Look here for a table of fuel names.

The orange glow of the "muter" is probably due to what some people call "under-burning", that is, the fuel vapor is burning under the "muter", rather than where it comes through the matrix of small holes on the sides. This can be seriously dangerous. You did well by going back to the spreader plate.

In a lot of countries like Sudan, you may be getting a fuel that has a lot of heavier hydrocarbons or even dirt. This clogs the fuel line, which could explain the shutdown. You might try overhauling the stove from pump to jet. I had to do this one time when I got some 3rd world marine diesel, thinking it would work as well as auto diesel. I was using my old MSR XGK at the time. I have a Primus MFS (Multi-Fuel Stove, the predecessor to the Omni) which I have used with white gas, kerosene, and autodiesel. To do this cleaning, you will have to take the pump apart to see that the gasket on the pump stem is not damaged or clogged and that the air valve and fuel filter are not plugged up. You will need to pull the cable out of the fuel line, clean it thoroughly with tooth-brush and alcohol or light mineral spirits, then use it as a "pipecleaner" to clean and then flush the fuel line. Be sure the jet orifice is not damaged and does not have "lacquer" or carbon buildup (use the Kerosene jet).

You could provide a bit more information, though, and maybe some close-up photos of the parts of the stove and pump.

7:24 p.m. on March 4, 2013 (EST)
0 reviewer rep
430 forum posts

First of all I am not familiar with this stove. I am not even sure i know what it looks like. bit i followed Bill S advise to see the flame spreader, and i see a tube that should get heated by the heat the burner makes to create pressure.

I do own 2 Svea 123 stoves,  a Svea 123 R and a MSR Whisper Light. The blue flame comes from the gas being 'Atomized' A vapr os created by the pressure and the heat.

A yellow flame indicates a 'Rich' fuel condition (too much fuel) or lack of air, and or lack of heat to create pressure.

Or poor quality fuel. I almost suspect that heat tube could be clogged.

 If this stove has a wick and has been allowed to run hard and out of fuel at the same time the wick can be damaged. I KNOW this can damage the Svea 123 and 123 R stoves. I just don't know if your stove works this same way.

I hope one idea or another helps.

12:43 a.m. on March 5, 2013 (EST)
0 reviewer rep
7 forum posts

Firstly thankyou so much for a reply its starting to make sence as to why its happening but I think another good clean may be what's needed. I have only been using unleaded petrol with the kerosene jet and has worked amazingly. We continued to use petrol in Sudan which was known as benzin but seamed oiler. I tried using the diesel jet which didn't make much difference and cleaned the whole system with an airline which made a bit of a differance but soon returned to the original problem. Maybe it needed better cleaning and that the fuel is constantly dirty so even after a good clean may clog up quickly resulting in a stove that doesn't seem to be fixed. One of the reasons for using petrol is ease of finding it as we are on bikes it's not always easy to locate other fuels and know what they are called add to this kids trying to mob and rob us as soon as we stop and trying to spot where we can buy food and eat in peace has recently been a bit of a battle hence going for the easy option. One thing that has been hsppening to the stove is where the fuel line meets the brass fitting on the stove the line is starting to squash due to unpacking and repacking is there anywhere I can source a new fuel line? The other is the flow of fuel coming through the line seems good and the filters look ok and have been changed would sit getting into the system also make this a issue? Thanks for links and advice it means a lot knowing there are people out there who can help :)

11:10 a.m. on March 5, 2013 (EST)
102 reviewer rep
2,295 forum posts

Perhaps water or mud in the fuel tank?  Did you try replacing the fuel in the tank?

Ed

8:16 p.m. on March 5, 2013 (EST)
12 reviewer rep
843 forum posts

sounds like bad fuel to me. the dirty fuel is mucking up the works. it needs a good clean, frequently as long as you are using that crappy fuel.

10:42 a.m. on March 6, 2013 (EST)
TOP 10 REVIEWER REVIEW CORPS
2,430 reviewer rep
5,314 forum posts

As I mentioned in my first reply to you, it is common for third world fuel to be fairly dirty. I have sometimes filtered the fuel, even for using it in a vehicle in such conditions. Get a piece of cheesecloth that you fold over to get 3 or 4 layers and pour the fuel through that before putting it into your stove's fuel bottle (clean the fuel bottle first, of course, since you probably have some junk from the earlier bad fuel in it). A cotton sheet can substitute for the cheesecloth, but wool or synthetics don't work well for filtering fuel. If you do not keep filtering the fuel, the lines will just get clogged quickly again.

The filter on the fuel line (the white cylindrical piece on the pick-up tube) might have to be replaced, since it can get so plugged up, it can not be cleaned. Worst case is having th get a new stove, hard to do in Sudan.

12:45 p.m. on March 6, 2013 (EST)
102 reviewer rep
2,295 forum posts

Bill S said:

As I mentioned in my first reply to you, it is common for third world fuel to be fairly dirty. I have sometimes filtered the fuel, even for using it in a vehicle in such conditions. Get a piece of cheesecloth that you fold over to get 3 or 4 layers and pour the fuel through that before putting it into your stove's fuel bottle (clean the fuel bottle first, of course, since you probably have some junk from the earlier bad fuel in it). A cotton sheet can substitute for the cheesecloth, but wool or synthetics don't work well for filtering fuel. If you do not keep filtering the fuel, the lines will just get clogged quickly again.

The filter on the fuel line (the white cylindrical piece on the pick-up tube) might have to be replaced, since it can get so plugged up, it can not be cleaned. Worst case is having th get a new stove, hard to do in Sudan.

 Paper coffee filters also do the trick.  As for new stove in Sudan; don't they still have those Optimus 00 models (or their follow on) in common use throughout that part of the rural third world?

Ed

1:07 a.m. on March 7, 2013 (EST)
0 reviewer rep
7 forum posts

I'm going to strip the whole thing down today as I've been sick for the past week. I have been trying to keep dirt out of the main bottle and even wait for a car to fill up at a pump then get mine after so I'm not buying the litre that is stuck in the fuel hose. The whole stove doesn't look that dirty but will change everything. One thing I've been trying to get a replacement for is the fuel line I've tried primus a couple times with no reply. Any ideas?

6:42 a.m. on March 8, 2013 (EST)
0 reviewer rep
7 forum posts

Stripped stove down to the smallest part changes all o rings filters and picked out a bit of carbon build up in the 3 grooves on the valve. Cleaned heat tube, petrol jet and put a plastic tube on the hose to keep to straight but is under burning I'm at a loss ?

10:03 p.m. on March 28, 2013 (EDT)
0 reviewer rep
430 forum posts

Once more I am not clear on what is taking place. if there is a plastic fuel line getting squashed that may lead to a lean fuel flow which could effect a burn. Not enough fuel.

If the metal pressure line has a dent nearer the cold fuel side before it is heated it may cause a vacuum effect and lessen pressure from building. Combine that with any carbon clogging and you will have a lean fuel burn probably.

I work as a industrial mechanic and some projects use a venturi we pump water thru to get vacuum chambers up to 27 inches of mercury. If this fuel tubing is acting this way you will need a new one.

i will go back to post one and see if i can get a clear view of this stove.

I would like to be of help, but i have no idea what parts are there. if there is dirt in the system I wonder if you see any German or Swedish car dealers in the area. If you do, you might have a mechanic blow out the stove with varsol. That is a fluid that cleans out fuel injectors under pressure.

10:12 p.m. on March 28, 2013 (EDT)
0 reviewer rep
430 forum posts

Is this the stove? 
Primus.jpg

10:17 p.m. on March 28, 2013 (EDT)
0 reviewer rep
430 forum posts

Something else i would like to know is what happens if you just pump up pressure and turn the stove on with out lighting it?

Does it still not flow out fuel well then?

Does the pump feel like it pumps up well too? Did you ever have to pump it up and pump it up under use as well?

I am just guess here the best i know how.. I never even saw one of these face to stove before. I wish i could get my greasy mitts on it just to be of use.

It may also be leaking down O rings.. how old is this stove?

If that is the stove what's a muter? Note if you click on the picture it gets bigger and is easier to read.

4:40 a.m. on March 29, 2013 (EDT)
102 reviewer rep
2,295 forum posts

How full is the fuel tank?  You need air space to compress in order to build pressure with the pump. Little or no air space will cause rapid depletion of pressure, causing the stove to sputter.  Try filling the fuel tank only 3/4  full then pressurize and see what you get in the way of performance.

Ed

9:39 a.m. on March 29, 2013 (EDT)
0 reviewer rep
430 forum posts

Lodge Pole said:

Something else i would like to know is what happens if you just pump up pressure and turn the stove on with out lighting it?

Does it still not flow out fuel well then?

Does the pump feel like it pumps up well too? Did you ever have to pump it up and pump it up under use as well?

I am just guess here the best i know how.. I never even saw one of these face to stove before. I wish i could get my greasy mitts on it just to be of use.

It may also be leaking down O rings.. how old is this stove?

If that is the stove what's a muter? Note if you click on the picture it gets bigger and is easier to read.

 Great point. I had meant to say that in my first post and see I did not.

I blame CRS. It's in the water.

October 25, 2014
Quick Reply

Please sign in to reply

 
More Topics
This forum: Older: Big Agnes tent zipper repair Newer: Attention Hilleberg Owners
All forums: Older: Tips for snowshoeing/overnight camping in Central Minnesota late March? Newer: wanted tents/to buy