filter BEFORE fuel pump?

[Alan Brase]

I was a little concerned that the Bus Depot and CIP tank sonly came in one part number for both the waterboxers Vanagons. Late 2.1 equipped cars have a 12mm hose from the tank into the fuel pump. So, I used a used tank from a different late Vanagon.
I found a lot of rust debris built up on the strainer INSIDE the inlet of the fuel pump. A shot or two of just about any penetrating oil will pretty well flush that away.
The next problem is that it is hard to find a quality fuel filter to go in the inlet line that is big enough. Seems like I found a NAPA one that was close. I also bought one of those hose pinch off pliers. it makes the job SOO much nicer to not have the danger of a gasoline bath when I do it. In fact, I now keep it in the Vanagon when I travel as part of the tool kit.
I initially bought one of those clear, cleanable filters as well, but abandoned it when I found out how soon it plugged and how hard it was to clean.
I had another earlier air cooled Vanagon suffering the same problems, and nursed it along for quite a while with just a small Fram G-3, I think, ahead of the VW inlet filter. I could unhook that Fram filter and dump out its gas and part of the debris well enough to keep the car going for quite a while. I'd agree, though, that whine is the death rattle! don't let it run very many hours that way!
Al
5 Vanagons, 56 single, 58 23 window

[shenan-agon]

Yeah, I've been doing a bit of research on cleaning/restoring tanks...don't think I want to spring for a new one just yet. This tank was just put in a year or so ago, and although I assume it was used, it was probably in decent shape. I still need to drop it and check it out (been out of town), but I think I'll start by just bringing it to the local carwash and spraying all the crap out of it. I'll take a look after that and see if I think it needs more serious measures like etching/sealing, or replacement...

[mjamgb]

Just went down this path with another vehicle... Definitely have the radiator shop do any work beyond simple sluicing out. They can pressure test the unit too (leak check).

Drawing air may be a pinhole in the pickup tube in the tank.

Fuel filters do not usually run "full" to the naked eye. Rather fuel goes through them as a "skin" along the surface of the filter. It is very common to get bubbles that are NOT from drawing air but from the vacuum on the fuel causing some of it to go to the vapor state (gasoline has a very high vapor pressure and very low BP). This is doubly true of upstream filters.

I suggest you dump the kaka out of the pump again, change both filters again and stock up on the $1.50 clear plastic cheapies, even after cleaning out the tank.

I further suggest you use "gas dryer and antifreeze" for the first fill-up after you clean out your tank to emulsify the remaining water and transport it out (via the engine).

Keeping your tank full of fuel is the best way to prevent corrosion. Sitting for a length of time can cause corrosion at the top of the tank from condensation.

Those "awful" filters are worst under pressure (i.e. on the delivery side of the pump). On the draw side they are under little pressure (negative, at that) so are less of a hazard.

The fuel pump does indeed make up to 100psi of pressure all by its very lonesome. The regulator merely regulates the pressure at the injectors by bleeding off fuel and returning it to the tank. There is no other means of providing pressure except in the mechanical systems.

In-tank pumps for FI only became common in the 80's. Nearly all previous EFI systems used either the Bosch or Lucas FI and were "outside" the tank.

Mike!