Innumerable Primus

I've come across a stove which may interest some of you. I'm a new member, but I've lurked on your site a while and I'm learning lots.
It appears to be an early one, c. 1890s, but may be an amalgamation of newer parts. I've tried to show the relevant components in my pictures. It's led a hard life and come a long way from home, found in western Canada

Long, sharply bent pot stands, no feet


Unlabeled burner


Tank seam isn't folded. Only mark is a small "Z" at the very centre


"PATENT"

"PRIMUS", without an insignia between I and M


"PATENT" "B. A. HJORTH &Co" "STOCKHOLM". Unlabeled vent screw


"F.W. LINDQVISTS" "PATENT"


"L" pump handle


Old NRV style with removable pump tube


No markings on burner, flame spreader gone. Hex nut attachment


Thanks for looking!

-Boreas

 

What a find, like so many earlier survivors it shows the evidence of a long and hard working life with numerous repairs and replacement parts.

A grand old piece of history. Looking forward to seeing it in action

 

Burner is later production but pump is second type - I think that style of pump was used on Primus stoves circa 1894-95 but the shape of the stove could be a few years later.

 

Wow @Boreas that could be a very early stove - B.A.Hjorth first took on the role of Primus stove sales agent in May 1892. That old pump with the peg-spanner fitting rather than a hex fitting lasted until 1895. So that gives a sort of rough dating window. But almost all Primus stoves from those years have a crescent shaped B.A.Hjorth provenance mark on the base of the tank in addition to the name on the filler cap. So the filler cap alone, and no sign of the Hjorth tank base mark may mean it could be as early as later 1892/early 1893?

 

Lurked you say, @Boreas Quite an introduction!

John

 

Thanks for the info folks. I think I'm going to like this little stove.
Intriguing to me that Mr. Lindqvist himself may have laid hands on the older components... perhaps not, but it tickles my imagination.
I gave it a light cleaning, oiled the leather, and got it pumping. There is evidently at least one pinhole leak, the tank doesn't hold pressure long before self extinguishing. It sweats fuel somewhere around the pump/tank joint when pumped. No wonder they went to the fixed pump tube and removable NRV.
I thought I might seal the tank and submerge it in hot water to see where the bubbles emerge. Maybe a drop of solder could bung it up. I imagine one of you has dealt with this problem before, any suggestions?

 

What part of Canada you from? (sweet old stove by the way)

 

Submerging underwater and pressurising the tank should give a stream of bubbles at the leak.

Another method which can make it easier to locate a pinhole leak is to brush on some washing up liquid mixed with a little water- the mixture will bubble at the point of leakage.

If the seals are in order and the pump is working, dab on some mixture around the suspected area of leak, block the jet with a finger and give a few pumps. Bubbles will confirm a leak and pinpoint the location.

Hope this helps.

 

That's good advice, thanks Blackdog. I've inflated enough leaky things to know the old soap trick, don't know why it didn't occur to me.

 

I have not worked on a stove of this era before, somebody who has may well offer more specific advice but I will add a few pointers, sorry if I'm teaching you to suck eggs!

If it's a pinhole in the soldered seam between the tank and the collar which the pump tube screws into, it will be a case of cleaning, fluxing and heating, possibly adding a little more solder.

Extensive cleaning will damage the beautiful patina which is part of the history of this beauty. So to start with you could try just cleaning back the smallest area possible in the vicinity of the leak, and soldering it using resin flux. If unsuccessful, try the same with more aggressive acid flux (see note below). If unsuccessful, you'd have to resort to extensive cleaning, or even dismantling the joint...

Applying heat to the joint from the inside of the pump tube may be better both in terms of appearance and giving the flux the best chance to do its work.

Acid fluxes will do a better job at cutting through lead and brass oxides to allow the solder to flow and take to the brass properly, the issue is that if not completely neutralised when the job is completed they continue eating away and can eventually cause problems. With a significant stove such as this, it's up to you whether you are willing to do your best at neutralising both sides of the joint, or avoid an acid flux altogether.

Resin type fluxes do not have much corrosive power, so do not pose a threat to the stove in the distant future. Very thorough cleaning will be needed, and in some cases complete dismantling and reassembly of an old joint may be needed.

I know it's your stove but please, please don't polish it

 

Thanks for the info and insight @Blackdog, and acknowledging my ownership . I don't intend to polish it to a high shine. I understand any changes I make may alter its significance in certain minds. I paid what little was asked for the exclusive control of it's fate, and it will continue to work until it can't, then it'll be fixed and keep working. Any changes I make to it will become part of its interesting journey.
Seems there is leaking at the seam between the tank and collar the pump tube threads into. Additionally, it leaks from threaded joint between the pump tube and collar. I don't have the peg-spanner to tighten the pump tube in place, and I don't want to put too much torque on it without the proper tool. Is there meant to be a gasket at this threaded joint?

 

The tank to collar seam leak should be easy enough to repair, but I'm not qualified about the pump tube to collar. Hopefully somebody else will chime in?

Great attitude though, it will be wonderful to have this back working again. In service repairs, ancient or modern, all add to the history....

 

blackdog, On first read i too got impression one leak was riser-to-tank. nope. 2 leaks as i understand it:
> leaking at the seam between the tank and collar the pump tube threads into and
> it leaks from threaded joint between the pump tube and collar.
both re pump.

@Boreas i presume you reviewed the other removable pumps with that fitment.
I do not have link to share, sorry, but i expect pump tube removal is a process that has been covered here, somewhere.
Good luck.
To answer one question, it does seem the threaded joint does not use any gasket or seal.
Many brass-on-brass threaded joints (including removable pumps) will seal by design, some with noticeable tapered thread, some are not. Do not overtighten btw. A thread paste/sealer is an option one might consider.

 

Thanks @OMC for your input. You're correct with the 2 leak locations. The pump tube has clearly been chewed on by someone using pliers, so it may have been over torqued already. I'll look in to thread paste, not something I've play with before.

 

Not sure I mentioned the riser anywhere, however I'm currently in hospital and the medicines have been causing some odd experiences.....

 

Get well soon.

 

@Blackdog,
yes, get well soon.

my bad all around. sorry. you're in the hospital on meds and had it right.
i went full-on confuser and i have no excuse

 

Thank you kindly both, keeping spirits up with thoughts of being outdoors with a classic stove soon! Sorry not a subject for the Reference Gallery I know

 

I’ve kept out of the discussion on the leaks as I’ve not worked on an early Primus with that pump fitting.

@igh371, do you have any advice?

Best regards

Tony

 

I don't want to hijack the thread with irrelevance, but I hope you are on the mend @Blackdog . I don't know what hospitals are like in the UK, but where I'm from, it's no walk in the park.
I'll continue to harvest from Blackdog's brain. How would one neutralize an acid flux to avoid further degradation?