Primus No 1020 age and seized solid NRV

Hi all, i received my new Primus no 1020 earlier and got stuck in straight away, the nrv is seized solid and at the moment i've only got Acetone to soak it in, will it do the job and if so how long should i let it soak for and how much force can i safely apply to try and release it?
The date code says AA with 6 underneath it, is that 1936?
Thanks.

 

AA is 1936, that is correct.

Are you sure you absolutely must remove the nrv?
Is it leaking, or is it just stuck when you try to pump?

Either way, it's not always needed to have it removed. Actually, it's seldom needed...

Have you tried the old remedy to pour a couple of table spoons of paraffin into the pump-tube, re-attach the pump and push it downwards in a prompt stroke?
You would be surprised how many times that is all it takes to sort of 'clean' a leaking nrv, or even loosing up a solid one.

 

@Carlsson

That's great thanks, its quite tidy as well for its age then, even the mica globe is in fairly good condition,

I must admit i got straight into stripping it down as it needs a clean, i never tried it to be honest, the control knob is quite stiff and the concentric? rod is stuck solid in the vapouriser so that needs freeing off too, i'll leave the nrv alone then and will test it before i go any further, i just imagined that it would not be working at that age,

Thanks.

 

Ah, I see.
Better to try things out first, and then judge what needs to be done.

Regarding the cleaning mechanism here... it isn't the concentric one.
It uses a rack and pinion type of cleaning needle, and they may get stuck by corrosion. They are both made in brass.

 

I'm so used to Vapalux, Tilley and Optimus lanterns with leaking NRV's i just took it for granted that this would be the same but it is my first Primus,

I've got the pump leather soaking overnight in neatsfoot oil so at some point tomorrow i will reassemble and go from there,

Thanks for the advice.

 

Can't wait to see some photos.

 

Hopefully i'll have it up and running in a few days, its even got the elusive spirit cup

 

I will agree with this.

I usually put some penetrating oil in the pump tub and let it sitt for avile and then reinstall the pump assembly and with a hard press the NRV normally start to work again.

I think I have needed to remove three NRVs over the 30 years I have been collecting stoves and lanterns.

Why remove something that do not need to be repaired?

Michael

 

@cmb56

You've been very lucky then, most of the NRV pips that i encounter have gone hard or perished (mainly Tilley and Vapalux) so i now just change them as part of the service,

I guess the Primus nrv is similar to the Optimus type?

 

@MG
Maybe I have been lucky but I have never had a NRV leaking so far.

The only one that I have fixed was for a friend’s Anchor lantern that was leaking due to rust in the NRV.

The trick with the penetrating oil did not work on that one but it was an easy fix when removed.

As long that the NRV is working and not leaking I use it.

Michael

 

@cmb56

I will need to pump some fuel through the NRV as it is leaking badly, i also need to replace the cleaning needle and probably the jet as i need to order parts, is there a special tool i need, i've got one for the Optimus but these look different or is there an Optimus/Petromax cleaning needle that will fit the 1020 do you know?

I've just filled the pump tube twice and pumped the fuel through, will it do anything if i leave fuel in the tube overnight and then pump through tomorrow or have i done enough?

Thanks.

 

If the NRV is leaking, and the method of filling the pump tube slightly with paraffin and pressing it through as I explained above doesn't help, I guess you need to change the NRV (or just the pip in the cup, if that's easier for you).
A leking NRV is either solved, or shown, directly in those cases when the "fuel-push-trough" is applied.

The cleaning needle on Primus lamps and lanterns is easier than others.
It just has a square shaped fitting, so any small adjustable wrench you have will be sufficient.

It is very straightforward, and it all will be very clear once you actually start to fiddle with your lantern.

 

Well hopefully pumping the fuel through will fix the NRV as it is seized solid in the pump tube and i am a bit concerned about causing damage so any advice with that is much appreciated,

Ah that's handy then,

Thanks.

 

My fight with an NRV from a Primus 1020 is a real horror story and well covered here on CPL! I had to remove the entire pump barrel but no worry, I really don't think you will have that drastic of a problem. I caused most of my problem with the NRV by destroying the ability to put an NRV tool on it and extract it! I think you will free it up by simply letting it soak maybe overnight then try again. I think it will loosen up!

 

No i don't want to have to remove the pump tube, that would be a nightmare for me too,

What should i soak it in? i've got some acetone, i think i read about mixing it with 3 in 1 oil, is that any good and what sort of ratio should i use?

Just pressurised it again after three attempts of forcing fuel through the NRV and its still leaking badly so the NRV will need to be removed

 

Personally, I use automatic transmission fluid but I've heard 3 in 1 is a suitable alternative, either way, 1 : 1 is the recommended ratio.

Henry.

 

I think Henry's advice is sound. If time is on your side then you have nothing to lose. Try it overnight and see.

 

@MG and @Henry Plews. I can’t vouch for the 1:1 mix of acetone and 3 in 1 oil but I can for the same mix of acetone and automatic transmission fluid (ATF). It works very well, surprisingly well.
Cheers
Pete

 

@Henry Plews @george @AussiePete

Thanks gents ATF it is then, i will buy a litre tomorrow, it should last me years then, i will be extremely happy if it works,

Is the Primus NRV pip the same size as the Optimus ones or a Vapalux as i have a few of those, i doubt my punches will go as small as that,

Thanks.

Should i refit with a lead washer and maybe some copper grease?

 

The concoction is in and hopefully working its magic, fingers crossed! i've also added it to a Vapalux lantern with a stubborn NRV for good measure too.

 

The NRV pip will be the same size as an Optimus one. Lead washer ? It depends on how original you want the lantern be. In the past, provided it wasn't too mangled, I've successfully re-used the original lead washer, I've also used a rubber washer in the style of Vapalux with equal success. The choice is yours.

Henry.

 

@Henry Plews

Thanks Henry, i was led to believe that this one probably wasn't fitted with a lead washer from new but i guess i will find out if i can get the blighter out, no joy as yet!

 

All the Primus NRSs I've worked on used a lead seal. I can't tell if they were replaced with these type seals or what, but I think they probably came that way. This seems to work both at getting it to seal and later, if you have to, removing it.

I do hope you get the mixture to work. There is nothing worse than a "shot" NRV that won't come out!

I know from personal experience!

 

@george

Yes all the Optimus NRV's i've come across are the same,

Thanks me too, apparently this stuff is good so i've ordered some just in case,

XCP ONE PROFESSIONAL - High Performance Multi Purpose 500ml *DIY Garage* RR33 | eBay

 

Well i couldn't wait for the XCP ONE to arrive so i went and bought some plusgas, its been in around four hours and still nothing, i'll just have to leave it in there a few days and hope it works, i've only got a generic NRV tool or one of Korean Simon's multi tools, both of which aren't that great to be honest and have some twist movement, do the original Swedish NRV tools fit well with no movement when in position?
What other options do i have without unsoldering the pump tube or trying to find a replacement tank please? i've tried the acetone and atf but i only left it in there for a few days, i've poured boiling water down the pump tube and i've tried tightening the NRV none of which have made any difference, i hope i can sort this out especially as its the first decent Primus lantern that i have owned,
Thanks.

 

God, talk about "deja vous"!!!! This is exactly what I went through!!! MG, unless you're good at soldering, please let someone else take it out, if you have to! I got my son to do mine. He does stuff like that. He has his own restoration business, so it comes easy for him. This almost brings tears to my eyes, I know what a struggle this can be.
Don't give up on "soaking". Let is stay in there for a week, if you have to. It's still better than unsoldering the pump barrel.
My Primus 1020 is dated 1935, and I got it from a dear friend in Holland so it means a lot to me.
Everyone on here has given good advice so don't give up the ship! Still upper lip, my friend!!

 

@george

It is certainly frustrating George! i don't have the experience to remove the pump tube so i would make a complete mess of the lantern and i don't know of anyone that would take on the job for a reasonable price either, i can leave it soaking for however long it takes but i'm not feeling confident that it will work at the moment, its a nice lantern so i hope i can get it sorted especially now i've bought extra parts for it.

 

Can you still get a tool on the NRV or has the top part been messed up? My pump barrel had to come out, I messed up the NRV so bad I could no longer get any took to work!
Stay with it. Keep some penetrating oil down in the barrel and if you can put something, anything down the barrel and slightly tap the NRV. Sometimes this is all it takes the slight tap can cause the oil to reach places better. Not hard, just a slight tap.

 

I haven't damaged the NRV as yet but the removal tools i have are not really a snug fit so if the original Swedish tool is of better quality and fitment then i need to source one of those,
I've been trying the odd gentle tap here and there in either direction trying to use the NRV tool like an impact driver, hopefully something other than the end of the NRV will give.

 

If the genuine Optimus NRV tool that I have is anything to go by, avoid them at all cost. My example is a spindly affair made from monkey metal and the first time I used it, it distorted both itself and the NRV I was trying to remove. I made my own which was a bit crude but it worked.

Do you mean they feel slack at the business end or loose in the pump tube ? Although a snug fit around the valve head is preferred, I think a small amount of play is acceptable as long as you keep the shaft / main body of the tool square to the object; have you tried bulking out the tool with insulation tape so that it's a tightish fit in the pump tube ?

Henry.