Thanks, you've been great and with the help of this....
http://vwdiesel.net/phpBB/viewtopic.php?t=1573I'm going to have a go at changing the cover myself, now I know what is underneath, and see what happens. If I take the shaft out I should be able to see some wear on the shaft if that is the problem...
I've got a couple of spare pumps I can use... one is an unknown and the other I messed up changing seals... I find swapping pumps a real pain and I don't like the uncertainty of just sticking on an unknown. (can't afford a pro rebuild

) If I could get one of the other pumps tested...
Wonder if I can swap the cover from a 1983 NA onto this pump?? ('87 with LDA) ...guess I'll find out... I'll put up some photos...
rubadubdub Taking the spring off is easy... There are 2 levers on top of each other. Take the nut off the shaft (hold the levers down) and mark it re. the index lines. Then remove the bolt that holds the levers together and they'll come apart. (the top part is the bit that moves the shaft, the lower part has the spring...)
Getting the spring back on is easy too... Screwdriver and a pair of longnose. Pushed it around from the back as far as poss with the pliers and then hooked it with the screwdriver from the front... (on one of the pumps, the spring can be put in place on the bottom lever, swivel it around to put tension on the spring, then put the top lever in place) You not got blowby or anything??