Hey,I'm installing a Napa 4770 base + 3405 water separator filter pre-pump, and I found a little rubber gasket in the filter box. The gasket seems too small to go over the threats of the 4770 base.
Should I just push this up over the threads and use it?
It doesn't look like it would do any good as the bottom of the thread neck seems to be recessed below the point that the filter would stop.
Click thumbnail shots to see larger size.
Can I use that 3405 on an 1999UD1800 e cyl diesel? It’s not recommended but someone has used it and I have a fuel problem