Good evening lads and lasses,
I had my injectors checked out properly earlier on today, on a very nice £14,000 bit of Bosch testing equipment. It's shown that three out of four nozzles are well past their best but instead of paying the usual £200 - £250 for reconditioned units, the technicians walked me through how to disassemble and and then re-assemble my injectors with new nozzles in a D-I-Y fashion. I have ordered a set of four nozzles at a cost of £80 from another local diesel injection specialist. He tells me that these nozzles are made on the same line as the genuine Bosch components in a Bosch factory but are un-branded. I don't really believe that but I'm willing to give them a try, with a saving of £86 over the Bosch nozzles. I have already cracked open and ultrasonically cleaned every component of two of my injectors and I intend to do the other two tomorrow. All being well, the new nozzles should be ready for me to collect on Monday and then all I have to do is whip the end caps off, lift my old nozzles out and slip the new ones in
I'll let y'all know how the engine goes after I've re-fitted the injectors and all being well I'll have done just as good a job as the man in the workshop for a lot less money.
Here are a few pictures I took just for reference. Don't worry! They have been re-assembled in a pristine clean environment, not the horrible splintery, dusty outside area that you can see in these pictures. Also, one of the components is out of place in these photos. I found this when I tried to re-assemble the injector and the internals just rattled around. That problem is now solved.
The results for each injector as provided by the Bosch testing equipment. As you can see, the wear is pretty even which means there is nothing untoward going on inside the body, just general nozzle wear:
Cracked open the first injector. Quite simple really. Support the injector body in a vice ensuring that the jaws are only contacting the flat surface of the injector and then use a deep 15mm socket to crack the end caps / nozzle holders off. Three were relatively easy, one took a bit more effort but they all cracked off without too much hassle. I was surprised to see how many solid / gritty particles there were inside what I would have expected to be a very clean, well lubricated environment:
Old Nozzle wear is clearly visible towards the end point of the needle. This wear (as well as the wear in the nozzle housing) is what reduces the 'pop' pressures and diesel spray pattern in my case. I expect that when I install my new nozzles, the lack of wear should bring my pop pressures back up to where they should be and obviously restore the spray pattern. I suspect they have never been changed before, so they could well have covered 100,000+ miles:
Reassembling the injector after ultra-sonic cleaning. I took Buster's advice in the end and decided to go ahead with my mums el-cheapo ultra-sonic jewellery cleaner and the results were stunning. Simply put hot tap water into the bowl along with some of the jewellery cleaning solution that came with it, turned it on and suddenly clouds of black carbon come swirling away from everything inside! It only works on 3 minute cycles but I found ten cycles (30 minutes) was more than enough to bring everything up nice and clean (i.e. the solution barely sooted up). I have also cleaned and re-installed the old nozzles just so that everything is kept in place inside the injector body. All that needs doing now is the cap removing, the old nozzle removing and the new one fitting in its place. The new nozzles should be ready for me to collect on Monday, so I'll post more then