I realised last night, that with a new puppy being collected on Saturday after which my time won't be my own, I had a small 'window of opportunity' today and tomorrow to pull the Vogel IG-38 controller and have a close look at it.
Photos taken of connections for reference, listed in my lab day book, wires tagged with 'flag ty-wraps' and I could then pull the unit out of the pump leaving the oily bits behind.
Case opens easily with the usual plastic ramp clips allowing me to pull the electronics from the box. Last time I didn't split the electronics - it consists of two PCBs separated by a third in a sandwich construction with soldered connections on headers holding it together. One main PCB has eight header pins and the other six, so I opted to unsolder the 'six pin side'.
Using my powered solder sucker and some flux the plated through holes seemed quite clean but rather than risk pulling the plated holes though the board I ran some low melting point solder into the joints - this stays fluid long enough just to pull the header pins out all together. A bit of a clean up with the sucker and flux followed by a squirt of brake cleaner and a scrub with a toothbrush and it's good for re-assembly when the time comes.
There is one socketed IC, three transistors, a bridge rectifier, five diodes, a handful of resistors and polyester capacitors and two electrolytic capacitors and two relays all powered by a tiny mains transformer. Also a rotary switch to set repetition time.
I will replace the electrolytic capacitors, try and open the relay cases and clean the contacts, then re-flow every joint on all three PCBs and also the terminal block.