Hi all, I've been having some issues with the XUD N/A lump in a 309. The idle's been a bit lumpy for a while but it generally runs alright, clears as soon as you rev it. I recently filled it up with a tankful of commercially-produced biodiesel and it threw its toys out of the pram, getting really smokey and very rough on idle. I drained the tank and refilled with normal diesel, it got better but it still wasn't right. I found it was pulling in air, so I replaced all the hoses on the fuel system, checked the filter etc but it's still not running right. I have tried running a test supply of fuel straight into the injection pump which also didn't work. Interestingly I tried running biodiesel straight into the pump and it ran exactly the same as on diesel, so I don't think the biodiesel is necessarily bad. The timing has been checked multiple times but I can't see any problems there.
After this, I had the injectors tested - they were found to be faulty, so were reconditioned. The car still didn't run properly after this, so I pulled a Bosch IP, lines and injectors from a scrapyard. After installing (changing the studs to the Bosch holes), the car wouldn't even start - sometimes it'll fire, but cut out straight away. You can sometimes catch the revs and keep it running, I did this and tried to adjust pump timing but couldn't get it running properly. I thought the new pump might be faulty, so I had it tested - no problems there. Compression is fine at around 380 psi on all cylinders, the stop solenoid has been checked by removing the plunger and refitting - no difference. If anyone has any suggestions they would be gratefully received as I'm more or less out of ideas
After this, I had the injectors tested - they were found to be faulty, so were reconditioned. The car still didn't run properly after this, so I pulled a Bosch IP, lines and injectors from a scrapyard. After installing (changing the studs to the Bosch holes), the car wouldn't even start - sometimes it'll fire, but cut out straight away. You can sometimes catch the revs and keep it running, I did this and tried to adjust pump timing but couldn't get it running properly. I thought the new pump might be faulty, so I had it tested - no problems there. Compression is fine at around 380 psi on all cylinders, the stop solenoid has been checked by removing the plunger and refitting - no difference. If anyone has any suggestions they would be gratefully received as I'm more or less out of ideas
Using tight-fitting bolts/flywheel dowel I got it timed up correctly and we're back in business. At least the Bosch swap's done and out of the way! Thanks for your help 