99 E300TD pre filter
 

can someone show me where this thing is? i have looked to no avail. on my 92 300D it's on inline on the main fuel line.

Put your finger on center of main fuel filter, 4"to left 10mm bolt holding pre-filter.

It’s beneath where the fuel line plugs into the top of the filter housing. It looks like a coffee filter or a pool strainer.

Don’t forget to renew the o-ring under the cap.

Sweet! I have the replacement and the oring, i just couldnt find it. I will look when i get home. Thanks for the help

Pro tip: park slightly nose down to help limit amount of air incursion.

Not too much or you’ll have a fountain.

thanks for the tip! it will be ever so slightly downhill. should I hose clamp the tank lines under the hood? in my 300D 2.5, it took me a few times to realize that if I took the fuel cap off it released fuel system pressure, should I do the same?

Pinching the supply line would be helpful.

There should be no pressure on the fuel tank in an IDI engine, the fuel is sucked from the tank by the lift pump. The lift pump is capable of producing some serious vacuum, enough to collapse the tank if the vent is clogged.

Not exactly. The tank vent has a valve that allows 0 vacuum (to prevent tank collapse), but ~1PSI of pressure in the tank. That's the brief "whoosh" that's often mentioned when the tank cap is cracked. 1PSI doesn't seem like much, and it isn't, but it's enough to help push fuel through the fuel lines which is the intended purpose. The pressure comes from expansion of the fuel as it is heated in the fuel heater and from passing through the IP, and the resultant expansion of the air in the tank as the fuel warms up.