I thought it was just the pump shaft seal that has gone.
Why are you pulling the whole pump apart ?
The shaft seal had gone and I had a spare pump.
So ... I put that on and it ran like pants. Lumpy tick over, stalling wouldn't rev. Tried priming it using the leaver on the lift pump ... that suddenly went free and just didn't feel right.
So ... I changed the lift pump and checked all the connections for air leaks and cracked all the joints at the filter, IP and injectors. No air, nice clean bio coming out.
So ... I pulled the IP diaphragm out and gave the stem a clean which seemed to improve things a little. Partially firing on 3 cylinders and completely missing on one ... lots of smoke!
So ... I kept starting it and trying to keep it running now getting a little response from the throttle. It got better and better, so much so that it ended up on full throttle all on it's own and wouldn't now tick over.
So ... I sprayed a little WD40 down the hole where the diaphragm stem goes and kept starting it and letting it rev it's nuts off briefly before stopping it. Eventually it cleared, ticked over as sweet as a nut and revved nicely.
Yes I thought ... but no ... looked under the engine and there was a veritable Niagara falls of bio from the cam belt case drain plug.
So ... I took the bloody thing out again and refitted the first pump. The leak on that, now I've bothered to check is actually quite bad too ... bugger!
So ... look at secondhand pump ... circa 150 - 250 quid, recon pump 400 - 500 quid.
So ... I investigate changing the seal. Cheapest I can find is 18 quid off ebay as part of a kit of seals. Transpires it an unusual size 20*31*7.3 and not an off the shelf item from a bearing stockist. I've found them cheaper in China but not surprisingly, on a long delivery.
So ... from reading on the internet there's no key between the drive flange and shaft, so I've printed a tool that locates in the flange and can have a thin cutting disc (screwfix do small discs 1mm thick) run across half the end of the shaft and into the tool. The tool can then be removed and the flange popped (loud bang is a better description as it was on proper tight) off.
So ... with access to the seal, you can drill a hole, protecting the shaft with a hose clip, and very carefully muller the seal to a point where it will pull out.
That the current state of paly. Awaiting confirmation from the ebay seller that his seal is Viton and it should be here Tuesday, although there's a Bosch stockist in Croydon I might try tomorrow.
Having now had a lot of practice at changing the IP, it should be quite a quick job to swap the pumps over again ... not building my hope up too much at this stage though!
Don't you just love Discos!
