I thought about the funnel, Parker makes one. 100.00 for a funnel makes you hesitate though.
This truck does see plenty of fuel going through it similar to your marine use.
I use about 50 gallons a day.
The bugs eating the tank is a new one , however ford had a major problem with these tanks. The seams would rot out.
My tank was changed at 60,000 miles. Piles of tanks sitting behind the dealership.

I thought it could be coming from the truck tank but when I seen the same thing in my reserve jug that Idea went away.

As you said the Mercedes has a good filter system. The tank screen has a finer screen than the original primary filter that the racor replaced on this truck.
It was 114 mesh screen. The new racor one is a 30 micron water separator.
My Mercedes primary filter shows some trash but I just wonder how much is on the in tank screen. Kind of hard to clean as often as well.

Excellent cars with lots of thought going into the individual systems.
Gotta love it !!

__________________


Experience : what you receive 3 seconds after you really needed it !!



86 300SDL 387,000? Motor committed suicide
81 300SD 214,000 "new" 132,000 motor
83 300SD 212,000 parts car
83 300SD 147,000

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95 Chevy 3/4 ton auto 160,000
03 Toyota 4runner 180,000 wifes