Re: Leaking Dash Pots

[<PGAHOWELLS@domain.elided>]

Hi Nick
Buy seals from Rimmer . I hope they are the part number  512317 (Rimmer
Catalogue)
Buy spare diaphragms in case of need.
You need mixture adjusting tool for Stromberg Carburettors.
Unscrew and remove damper.
Remove carburettor top screws, after moving air pipes. Don't lose brass tag
with carb number.
Remove spring, diaphragm noting there is a positioning lug, and then, air
valve assembly. Watch out its full of oil which needs pouring away.
Turn air valve over and observe position of delrin,(Plastic washer)  on the
needle as best as you can. i.e. is it dead level with surrounding metal, or a
bit above or below. 
Remove needle by unscrewing it with the mixture setting special tool. If you
don't have one of these you must get one.  Pull needle out by hand not with
pliers.
Push up with thin instrument to remove the needle adjusting screw and the
cogged spring retaing clip ring through top of tube.
Remove seal ring from needle adjusting screw , noticing how flat it is, and
replace with new one.
Clean up inside of tube with emery paper on a pencil in case cogged ring has
scratched surface, as such scratch will damage ingoing new seal. Of course if
this has been done too much before the seal possibilty will be reduced
Reassemble trying to get the delrin exactly where it was before.
Refill with SAE20 50 or similar engine oil, but not 3 in 1
Reset mixture if necessary using the special tool.

Dashpots no longer leak.
If they do then the tube is worn, or the seal was damaged during fitting.
Hope it helped.
Peter