Like Martin, I'm also having pump problems with my re-build of a Tilley 246B. I've got a new leather ( from Tilley ) which has been well soaked in oil, springs and valve. I've cleaned the inside of the pump tube and have re-assembled 20 or 30 times but something's going wrong. Sometimes the valve won't open and I can't complete a full stroke other times it seems it won't overcome the valve spring pressure and then occasionally I think I've finally got it, re-fit the pump to the tank and it won't buld up any pressure. Is there a knack or secret to re-building the pump ? I have a suspicion it's to do with the position of the rubber valve. The tank is good and the washers are new. Any help greatly appreciated as I wasted hours messing about with this yesterday.
A new non return valve and spring which came with the Tilley service kit was fitted. I have even tried re-fitting the old valve to see if I can get the pump to work properly again but no luck. I know this is not rocket science but I just can't figure out whats going wrong.
Have you got the spring and seal in the right order? The seal cover the hole in the bottom of the cylinder and the spring pushes it up. Up means with the pump piston knob at the top.
Yep, plastic seal over the hole spring behind that and tightened down under the screw cap. I played around with it for half hour tonight and the first time I re-fitted it all together the piston traveled 3/4 the way then air locked solid, the seal wouldn't open.I suppose this proves the new leather cup is doing a great job. Took it apart again re-fitted with the seal in a slightly different position and this time the pump is too weak and just barely pushes air past the seal. I'm beginning to think maybe the whole assembly is worn out and needs replacing. Wish I'd bought a Vapalux.
There's only one position - or possibly 360, but each exactly the same. This is an X246B, isn't it? - with the shaped NRV seal and IIRC, a slightly tapered spring. The small circular spigot on the back of the seal fits into the smaller end of the spring... You said it!
Yep, that's the one. The 2 springs I got from Tilley are not tapered, exactly the same both ends. When I said alter the position of the seal, I meant have it dead centre or off to the side a bit which seemed to make a difference to the way the pump performed. Anyway, I think I've wasted enough time on this. Thanks to all for the replies. Going to look around for a Vapalux to play with.
I've just noticed you said "plastic seal" - it's meant to be some sort of artificial rubber - probably nitrile at a guess. It's meant to have some 'give' in it to accommodate variability in the pump outlet. If yours is hard - and a newly-supplied one could be if it's been in storage for a long time under unsuitable conditions - then it'll not seal. I think trying to affect where the seal sits as you assemble the NRV is a non-starter. If the seal and spring don't centralise as you're tightening it up, then they will with the first pumpstroke...
