Use of biodiesel has caused my factory priming system that is built into my water/sediment trap to be rendered non-functional.
In my case, the non-return valves gummed up, so I had to remove one set and may need to remove the second.
Others I know of report that the bio has attacked the rubber diaphragm in the hand primer such that they have had to remove it to stop air leaks.
For the last 2 years I have had a (what now appears to be an imitation) Facet-brand electromagnetic pump installed in-line between the fuel tank and water trap. Most of the time it has no power applied and the IP is able to suck fuel through it. When I need to prime after a filter change or some other work, I connect the power and pump fuel through it until all air is purged back to the fuel tank through the IP return line.
Recently, I have had fuel starvation issues outlined in the recent thread titled "Engine fulling issues". I eventually put it down to a failure of the Facet pump causing the line to be blocked such that the IP could not draw fuel through it anymore.
I borrowed another genuine Facet pump and temporarily replaced my failed pump and had no problems for 2,000 km. I have now bought another knock-off ($17 on eBay) and immediately am having the same symptoms again, albeit not as severe.
I feel this method of priming is not sustainable, so am interested in what others have done to replace the factory primer on their vehicles. Johnnojack outline a vacuum method that is working for him in the aforementioned thread, but I am interested in whether anyone else has a good idea.