# Jotul NR 404 Cookstove Rebuild



## Amphibian (May 17, 2011)

I've just obtained a JÃ¸tul NR.404 Cookstove that I'm about to completely rebuild. I've never rebuild a stove before so I thought I'd start a thread here to gather any advise I might need.


When I took delivery of the stove it was clear many of the plates were mating quite poorly, plates were not meeting closely here and there as it would seem gaps had just been cemented without ever being pulled together, at first I was worried the plates might be warped, but having dismantled the stove I can see they're not.


What I am planning on doing is this.


Dismantle the entire stove.
Clean rust of every surface I find it.
Paint each exposed metal surface with stove paint (the exterior is enamelled so won't need this)
Reconstruct the stove sealing every joint with furnace cement.


Is this the right plan, or am I missing owt?


The fire bricks are cracked, should I replace these? If so they are curved bricks, is it going to matter if I can't source identical bricks? Could I use mouldable fire bricks moulded to the same shape? I notice that there is no fire brick at the back of the firebox, is this simply missing or correct for this stove, the flames are drawn out the front right of the firebox, so maybe it's not a very hot area.


The flue spigot is damaged, in that the eyes through which the bolts pass have sheared off, will it be okay to weld new eyes on to this, or would the welds fail under the heat load? If it can't be welded, does anyone know if the spigot on the 404 is the same as the one on say the 602, the part numbers are the same apart from two numbers added at the end, which I think refer to the colour of the enamel only, so a new spigot can be sourced.


The US manual for the 404 refers to a flue adapter, which changed the diameter from the 125mm of the spigot to the 6" of the stack pipe. US manuals for the 602 also refer to this adapter whereas European manuals for the 602 make no mention of an adapter and so I assume it is safe to use 5" pipe and skip the need for an adapter, any opinions on this? European manuals for the 404 are unavailable. It is a rare beast apparently.


Lastly does anyone know about the doors on these things, there seems no room for fire rope, but I assume they had some kind of gasket at some point, does anyone know what kind of gasket they used, or any suggestions to ensure a good seal when the door is closed?


Thank you for your help.


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## webbie (May 21, 2011)

I can start you off on a few of your questions....

1. Yes, it would be OK to adapt 5" pipe to the flue collar. This may require a super-crimp in order to have the pipe fit into the collar. Also, you probably could obtain a sheet metal or other adapter to 5 or 6"...from a place like woodmans parts plus.
2. Door gasket - if there is not a clear channel for gasket, this may be one of many stoves that does not use a gasket, but a metal to metal seal. Morso, another European brand, also did things this way. Small air leaks in a cookstove are not something which is a problem - they may even be designed in.
3. Your basic rebuild plan sounds fine - you do not have to paint the inside of the stove - you can simply clean the parts fairly well and maybe spray them with a bit of light oil. No harm in painting, though......
4. As to the flue collar and the missing eyes, there are probably numerous ways to do this. Someone who knows what they are doing can properly weld cast-iron, but if you are DIY I think it could be done in other ways. For instance, a U bolt could be drilled though the flue collar and perhaps serve as the eye. Another way would be to create an eye of sorts out of cast metal - aluminum, iron, brass, etc. and tap two holes in the bottom of it, and then run some small screws through holes that you drill in the flue collar. Even a heavy piece of sheet steel or stainless steel bent at an angle might suffice as this "eye".


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## webbie (May 21, 2011)

Oh, yes, as you mention you can probably get a new flue collar for it. A plain painted one will cost less than the enameled replacement.


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## Amphibian (May 21, 2011)

Thank you for your informative replies.

In the case of the gasket, there is no clear channel. I just assumed there would be a gasket. Feel a bit uncomfortable without one, would it be possible to rig one using say ceramic paper, cut to overlap the lip on the stove body.

At the moment I'm not sure you could describe the door as having a metal to metal seal, metal to metal, yes, but no seal to speak of, maybe I need to check that the loop the latch drops into is not bent and causing the doors to sit poorly.


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## webbie (May 21, 2011)

It looks like there is a channel in the door in this pic......and a gasket also.

metal to metal seals would have a machined flat surface. Gasket seals usually have a channel in the door (as shown) which contacts a raised part of the stove body.

The gasket is quite flexible - and can even be obtained in various densities. In this case, my guess is that it is a 5/16" gasket glued into the door channel.


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## Amphibian (May 21, 2011)

That picture is the same as my door, but it really isn't a gasket. The bit running around the edge of the door is a protruding ridge of metal, which sits against another similar ridge on the stove's front plate. so looks like a metal-to-metal seal to me. However this fails the dollar bill test very easily.


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## webbie (May 21, 2011)

I would not hold a cookstove to the dollar bill test! A cookstove, by design, is not a smouldering air tight.  
If you end up needing to control your draft a bit more, use a turn damper or barometric (or both) in the stove pipe.


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## jimbom (May 22, 2011)

That is really a nice looking stove.  Somebody stop me before I spend again.


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