I recently pulled my sump tank and fuel tank for inspection (thankfully zero pinholes on the underside of the main tank; infamous rivet has been dremeled to a stub now). The sump tank was unsurprisingly filthy and has been soaking in POR-15 for several days while I await tank sealant delivery, and the pickup filter was naturally disgusting.

I've read about Kirby's recommendation to install in in-line fuel filter in between the pickup and the fuel pump, and then completely eliminate the old pickup filter. Good thinking.

But here's where my "lump'd" car differs: I have no electronic fuel pump, instead my old 350 runs off a mechanical pump in the engine bay. This means that the hose which typically runs like this: sump pickup --> fuel pump --> "main" fuel filter (the big cylindrical one) --> engine, instead looks like this: sump pickup -> main fuel filter --> mechanical fuel pump in engine bay.

It would seem redundant to place an inline filter in the typical spot (hose between sump pickup and fuel pump) since it would look like this: sump pickup --> inline fuel filter --> main fuel filter --> mechanical fuel pump. That's back-to-back filters.

In the original setup, the positioning of the additional inline fuel filter makes sense: it spares the fuel pump. In my case, since the "main" fuel filter is upstream from the mechanical fuel pump, it would seem I don't need to worry about the fuel pump getting a clean supply of fuel. Instead I would be interested in adding an inline filter to help prevent the sump tank itself from getting disgusting so quickly.

Would it be possible/wise/useful to place the inline filter in the supply line from the main tank to the sump tank (which, if I understand the diagrams I've seen, is the hose running from the base of the main tank to the side of the sump tank)?

Thanks

 

I can’t see any downside to what you’ve suggested.

Let’s hear what others have to say

Cheers
DD

 

If you do you may want to consider looking for some kind of valve - I am - it is crazy the messing about you need to do to prevent fuel going everywhere. Like this (sorry it is a UK site but there must be something stateside) Fuel Tap - I don't know how practical but I'm not a fan of hose clamps. I plan to install a Sytec bullet 10 micron filter before the sump tank but that's because I just invested time and money cleaning out everything incl injectors, I was going to put a glass bowl filter in so I could detect / trap water but I'm not sure they can handle the flow rates - I may get one just to see.

Something like this





You don't need anything massively expensive as a filter though - if you browse YouTube at all go find Derek - Vice Grip Garage - he buys very simple in line disposable nylon filters by the case.

 

The fuel tap/valve makes sense: greater safety, less mess.

For those not going that route I’ll mention that a wooden dowel of correct size makes an excellent hose plug. Tapered at one end on your bench grinder, it can be very quickly inserted in the hose. With planning (that is, be ready to move fast) you can keep fuel spillage to just a few spoonfuls

Cheers
DD

 

Ben
I do not trust fuel taps! I agree with the idea, and I have a tap in my garage that I bought; but I reckoned it would inevitably leak at least enough to produce fuel small, so chickened out!
An inline pre-filter is what i have too, and with that, and the filter after the sump tank/pump combo, I think a glass bowl would be unnecessary, and maybe even screw up throttle response. This is my setup:

1/2 inch WIX inline filter between the main tank and the sump tank.

Sytec bullet filter after the pump. All gets covered by the OEM metal cover, but the pump and filter are much easier to access. It also removes about 6 feet of tubing from the OEM system.

 

Greg - ya did it again - good plan get all that stuff out of sight - the glass bowl as I mentioned was just an idea not a commitment - I'm also concerned re flow through such a thing, the Sytec bullet is exactly what I plan to fit. I am stil looking for a way to isolate the tank it is truly ridiculous that there is no way to work on the filter etc without fuel going everywhere - lilke many I am tired of the fuel stink in that area and it does penetrate the cabin, all fuel hoses have a degree of permeability. A much better solution would be to use only hardlines in that area but that is a challenge because of the fittings - perhaps I will investigate more but I need to remove fittings to do so. I believe the only 'simple' solution is a barrier hose like Gates Barricade 4219BF. You need to be so careful buying fuel hose now as the market is flooded with fake **** - which I found out the hard way on one of my other cars - R9 that rotted out in less than 2 years - clearly was not R9.