We recently converted our 1984 MB 300TD wagon to run on waste vegetable oil using the STC100 from mercedessource.com and all was going well, the car was running fine until it stopped running. The tank is currently full of high grade olive oil, this is our second time filling it with that and we had a few moments when the engine wasn't producing adequate power but nothing more severe than that. Now, however, the engine will turn on but won't stay on. We went through a trouble-shooting list and did the following:
1. checked that hose clamps were tight
2. checked that hand primer pump wasn't leaking
3. bled air out of system at injectors
4. double checked hollow bolt was replaced with solid bolt at top of factory fuel filter
5. checked to make sure we didn't mix up hard metal fuel lines.
After all of this, the engine won't stay on.
Our Hanes manual (which obviously isn't designed to address WVO problems) suggests that if this type of thing happens it might be a clogged fuel filter, or a problem with the fuel injector (which our mechaninc has told us is often a problem with WVO MB's.)