My 300D-t had been idling rough and had reduced power until I replaced the leaky hand pump, this morning (I strongly believe it was allowing air bubbles to get into the injector pump - or at least wouldn't bleed the system properly). It idles smooth, after starting, now and power has been restored. HOWEVER, there are air bubbles in the pre-filter that I cannot rid of. Is this normal? There are NO more bubbles in the clear lines from the fuel filter to the injector pump; should I just not worry about bubbles in the pre-filter?
Let me know what you guys think. Thanks...

I don't know about bubble"s" (plural) in the filter, but there is always, or at least almost always, one big bubble in the top of my prefilters. If the car is running well and starting well, then everything's cool.

Have a great day,

There is an air bubble in my primary (small) filter too. It would only be removed if the filter was verticle. Any air in the system is automatically bled by a small hole in the top of the secondary (large) fuel filter which routes the air and some fuel back to the fuel tank. ~~~~~~~~~~~PEH~~~~~~~~~~~~~