Lister L fuel/oil pump

Hello, i have been trying to stop a leak on the fuel side of the pump on my 1918 Lister L , i have tried various ideas none of which seem to work. I have just purchased another pump of ebay but it is different to the original one and i think it is off a newer model, this pump has brass plungers that are hollow underneath with a spring and ball bearing it would appear that the original springs have been taken out as one is missing and the other is way to short. Could anyone tell me what size springs should be in them ? and where to get replacements? and what would you use instead of the asbestos string as you can't buy it now? cheers Paul.  

is the plunger worn these pumps can wear very badly on the fuel side ,as it is not as well lubricated as the oil side .if the plunger is worn then it is best to get a local machinist to make a new one .they are simple to make just a piece of brass bar and i use ordinary gland packing from a local plummers merchents

oliver wrote:is the plunger worn these pumps can wear very badly on the fuel side ,as it is not as well lubricated as the oil side .if the plunger is worn then it is best to get a local machinist to make a new one .they are simple to make just a piece of brass bar and i use ordinary gland packing from a local plummers merchents

The plungers seem ok, it has the usual asbestos string around them, as i say the trouble with the new pump when it arrived there are no springs in it , if anyone can tell me what size the springs should be i would be grateful