SVEA 123 r - Filler cap rubber valve (Midi Pump type)

Hi.

The non-return valve in the midi pump type filler cap is made of rubber. The one in mine is hard, heavily indented and leaky. Is this item available as a spare?

Regards: Jim Ford

 

Hi Jim,

I?ve the same problem (https://classiccampstoves.com/threads/226
unfortunately I don?t know to if this item is available as a spare, but disbelieve it because when it would be, there is less chance to sell the tank lid wich doesn??t get damaged so fast.

Maybe try to sand the rubber surface a bit, was trying it this evening, and it looks very promising but then the rubber get flung in my workshop --> no way to find

But I found a workaround, wich is possible when the rubber is loosed.
A stripe of a evazone insulating mat instead of it and Hunter worked, only every second there got a air bubble out. The material is not heat resistant so it?s really only a emergency solution.

Regards: Christoph

 

The problem stated is pretty common among the previous discussions.
Remedy is easily available by punching a pad of Nitrile rubber for a similar size plug. Just push it into the tiny spring and you are ready to go.
Tip: one may need to find the optimum tension of the spring that allows the ease of pumping action. Too strong the compression, hard to pump. Too light the compression, the risk of air leak.

E-mail me your address, and I can make a few for you. I received a patch of the material from CWilkins, and I am afraid it will last me a few years.

 

Hi bark2much,

is the offer also for me ?

Or is there a more common usage of Nitrile rubber ?
thus I could ask in a local hardware store.

 

Ja, Wohl! Just PM your address.

 

Thanks for the replies and the offer from bark2much (which I may yet take up on). I've got some PTFE rod that I might turn down to make a valve. It's heat resistant and sufficiently yielding to make a good seal. I'll report back if I do try it.

Jim Ford

 

I received the Nitrile rubber from bark2 much today.
It works very well

tank you very much !!

regards,

Chrisotph

 

I actually thank CWilkins for the generous portion of slab of rubber that solved a lot of problems for me. What you have is a section from the slab.

 

In UK you can get Neoprene which is pretty much the same thing. Where I buy mine they will sell any length you ask for but you have to have the full width of the roll (c. 1.5m)
I needed a piece 200mm dia. a few months back & now I have a mountain of the stuff - trouble is, its 3mm so it is a bit thick for most stove jobs.

 

Hi Ian,

I have never seen this material before and would describe it as rubber
If you mean the Neoprene the frogman has on his skin ? its very different, the Material I got from Bark2much today is much harder than the neoprene I know.
Even if there would be another material/source for me I find it really 8) to have a rod/gasket from the USA in the Cap, and be happy.
I?ll probably tell every one I meet on my trips the story of the Californian "gasket"
So the Stove has got written another history.

regards

Christoph

 

I bought a pack of tap washers from Wilco's, six washers for about 35p and have fitted them (after triming) to a couple of stoves and there have been no problems (are the washers neoprene?)

 

I used Neoprene rubber washers in Optimus caps with moderate success. Neoprene expands about 50%, when in contact with white gas. It will do the job of sealing the cap, but it becomes puffy, and easily damaged.

It is no good for the relief valve or check valve, for its expanded size grabs the surrounding wall, and the relief valve would not budge properly, and the check valve gets stuck in whatever the position it chooses. It gets hard to pump, for the rubber plug in the check valve increases the resistance: your thumb will tell you how a tiny bit of a softened rubber can make a difference in pumping.

Since it spends its time submerged in white gas, it eventually disintegrates.

 

Nitrole is the only way to go.
It will stand all types of fuel we use. Tests (from the makers) show this will out last every thing else.
Use the right thing first up. Then you wont have to do this job again for many years.
Send me an email stating the thickness, and I will send you some in an envelope. The postage is worth more than the product.

 

If anybody need some Nitrole "gaskets" now, surely I also can send him some from the large source I own now
Just PM Me

 

'O' rings in the gas turbine helicopter engines I was involved with in my last job, were made of 'Viton A'. The material was very durable and heat resistant. Not sure where it can be obtained by the likes of us though.

Another point regarding the valve is that the spring appears to be made of copper beryllium alloy. A nice touch as it's heat and corrosion resistant and used to be used for racing motorcycle valve springs long ago (not sure now, though). The pressure relief valve seems to be steel.

Jim Ford