Hi i have been given a tilley 246a I have changed the washers on the pump but cannot get the lamp to pressurize,using the pump from another lamp,it pressurizes. thanks for any help boater john
BJ, A soak in olive oil for the pump washer,is it opened up nicely? they can go a bit sideways,,,, try taking the NRV out and pressurising your thumb....if that feels ok then is the NRV not working letting all the pressure back past the pump?,
Hi bj thanks for the info will try that soon, I soaked the new leather washer in oil,it was bigger than the one i took out, i have put the old rubber one back in,if it is the n r v will that mean another pump. regards boater john
BJ, its an easy fix to replace the nrv seal and check the spring , from experience an A is easier to unscrew than a later pump,
Got a similar problem on my X246 (first ever lamp) Repalced all the washers but when pumping it starts to blow parraffin back out where the pump rod goes through the nut. As there is no rubber washer there to stop it, I am assuming the seal should be created by the leather pump washer in the barrel. Is that correct?
No, that is the job of the non return valve (NRV). Which model of X-246 do you have? Perhaps you could add some photos, that would help. The NRV., is located in the bottom of the pump, unscrew the nozzel and you should find it. If it's an older lantern then there should be a spring and a seal holder which looks like a small brass golf tee, the rubber seal fits into it. You will need to get a new seal and they can be obtained from the fettle box on this website. The other type of Tilley NRV., is a spring with a shaped rubber seal set into, do let us know how you get on, Jeff.
No! You will need to replace the rubber pip in the non-return valve at the bottom end of the pump. I find that the current type squared-off rubber pip makes a better seal than the original flat disc-in-a-holder type.
No! You will need to replace the rubber pip in the non-return valve at the bottom end of the pump. I find that the current type squared-off rubber pip makes a better seal than the original flat disc-in-a-holder type.
As has been said, the culprit is the NRV (Non-return valve) at the bottom of the pump. Essentially there's no difference between pressurising a lantern tank and blowing up a bicycle tyre. Does the leather pump washer in the inflator hold the air in the tyre? Of course it doesn't - that's the job of the tyre valve, which is the equivalent of the NRV. There's really no difference between the two main types of Tilley NRV - two slightly different engineering solutions to the same problem. Knowing Tilley, the cynical amongst us might say that the later, squarer seal without the little brass cup was the result of penny-pinching rather than an improvement in design - and they'd be correct...
An old definition of an engineer is a bloke that can make for five bob what any BF can make for a pound. Nothing wrong with penny pinching but in the case of Tilley they did take it too far with chosing alluminium for the parts and tweaking the tank design. That later NRV works fine so is actually one of the more reliable bits of engineering in the later lamps. ::Neil::
cheers guys. I already changed the washer/seal so that's what threw me. I figured it out though, it's the spring that is too weak and not holding it shut. I bought the seal kit from a guy on here but it doesn't include the spring like the Tilley kits do. I found one in my box of bits that fits and it's doing the job now, no blowback but it is maybe a bit too strong cos it takes quite a lot of effort to pump now but at least I figured the culprit. Might get to lighting it soon. Put a new mantle in. Is it better to set fire to the new mantle first to get it's shrunk down shape before heating up and lighting with the paraffin?
That sounds like you bought the equivalent of the Tilley 498 seals kit from whoever it was here. That doesn't include a spring, nor a few other bits - replacement knob etc. What you needed (and you're referring to in your post) is the Tilley SP1 service pack. That contains all the seals in the 498 plus all the other little bits, including the spring. I've never had any trouble with the NRV spring but, to be honest, I rarely bother with Tilleys, especially anything newer than the mid-50s. I've heard people stretch them slightly if they've become weak, or replace them with shortened ball-point pen springs. Hope that helps...
