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Sun Jul 08, 2018 5:21 pm

I posted the question in another threads but it probably doesn't get much visibility there. https://www.thesamba.com/vw/forum/viewtopic.php?t=700752

I started doing the fuel lines with the vanagon.org kit. I'm working from the back to the front i.e. starting with the injectors but am starting to think about the tank end of the lines.
Although I drained the fuel tank as best I could and put in a lot of fresh fuel I cannot be sure what crap is sitting in the bottom of the tank after all this time. At some point I will replace it but for now it's staying as is. Seeing as I'm doing the lines I was wondering whether it might be good to temporarily put an inline filter between the tank and the fuel pump i.e. in the non-pressurised section. Does anyone see any issues with this in terms of fuel pressure to the pump or other issues that I haven't considered? The idea is to save my fuel pump a bit from the unknown gunk in the tank and change the filter every month or so until I get around to replacing the tank

Sun Jul 08, 2018 6:21 pm

I run a filter between the tank and the pump. It’s probably unecessary but if you start getting stuff in the first filter you know your tank is junk and it’s time to change it. When these vans were a lot newer aftermarket tanks were not available and oem tanks were a lot of money so I would try to save them. Today aftermarket tanks are pretty cheap and it’s just better to change them. But I still makes me feel good to have both filters. John

Sun Jul 08, 2018 6:27 pm

Early model years did indeed have a filter before the pump.

Dave

Sun Jul 08, 2018 6:41 pm

Yes, your 85 & my 84 both left the Fatherland with a filter between the tank and pump.

I still use that one though many here recommend using a filter after the pump.

Possibly the pre-filter makes the pump work harder but it has never been a problem for me.

The original style is a Fram G3743 or equivalent:

Sun Jul 08, 2018 6:47 pm

Like djkeevs said, thats exactly where the filter is on my 80 air cooled from the factoryI also swapped out my original tank and when i dropped it, it was spotless inside! Just the outside seams were starting to fail

Sun Jul 08, 2018 6:48 pm

I switched mine out when I got the tuneup kit with the upgraded filter from go westy. Which has a good read in that:

http://www.gowesty.com/tech-article-details.php?id=115

You may want to get the other two kits. The plastic feed and return lines and a reseal kit for the gas tank. Make sure You get the rubber ring for the fuel sender and two grommets for the expansion tank float valves as well. I just redid all of mine. It was a chore. Getting the line off the injectors was awful. Dropping the tank sucked, but I’m safe, it doesn’t leak when I fill up or ever for that matter and I’m not going to explode in a fiery ball of death.

The only lines not in the kits are the small 5mm or so that are part of the evap system but those seemed pretty good after being cleaned up.

Sun Jul 08, 2018 6:57 pm

Great, thanks for the replies.

I just went digging through my parts and actually have one of these that I got from Bus Depot a while back that is similar (although it's marked as part # GF132) http://www.busdepot.com/133133511

The direction of flow is indicated as being from the smaller inlet to the larger outlet so I'll have to see if I can use the 1/2" hose in the kit for both sections (tank to filter and filter to pump) or might need to use some different hose

Sun Jul 08, 2018 6:59 pm

bretly wrote: I switched mine out when I got the tuneup kit with the upgraded filter from go westy. Which has a good read in that:

http://www.gowesty.com/tech-article-details.php?id=115

You may want to get the other two kits. The plastic feed and return lines and a reseal kit for the gas tank. Make sure You get the rubber ring for the fuel sender and two grommets for the expansion tank float valves as well. I just redid all of mine. It was a chore. Getting the line off the injectors was awful. Dropping the tank sucked, but I’m safe, it doesn’t leak when I fill up or ever for that matter and I’m not going to explode in a fiery ball of death.

The only lines not in the kits are the small 5mm or so that are part of the evap system but those seemed pretty good after being cleaned up.

Cool, I'll take a look at that too. Cheers

Sun Jul 08, 2018 7:54 pm

77 Deluxe wrote: ...might need to use some different hose...

I think you'll need 5/16 for the inlet and 7/16 for the outlet. At least it does not have to be fuel injection rated as both are very low pressure.

You may find it helpful to write the date and mileage on the filter to keep track of how long it goes before requiring changing.

One clue that it needs to be replaced is a change in the sound of the fuel pump - noisier and perhaps a higher pitch.

Sun Jul 08, 2018 8:23 pm

Ahwahnee wrote: 77 Deluxe wrote: ...might need to use some different hose...

I think you'll need 5/16 for the inlet and 7/16 for the outlet. At least it does not have to be fuel injection rated as both are very low pressure.

You may find it helpful to write the date and mileage on the filter to keep track of how long it goes before requiring changing.

One clue that it needs to be replaced is a change in the sound of the fuel pump - noisier and perhaps a higher pitch.

Good advice and thanks for the picture

Sun Jul 08, 2018 9:58 pm

I have a '90, with stock big Bosch filter after the pump.
Felt weird not having anything before the filter, so I added a standard Napa filter

https://www.napacanada.com/en/p/NGF3033

I guess that works too? How long before I change this filter ?

Sun Jul 08, 2018 10:41 pm

The original cube filter before the pump was pretty small considering the amount of fuel that the pump can push through the system as a result the pump would often cavitate and make a racket. I used to have to change the filter frequently on trip where the fuel in the tank was being continually agitated. Since I eliminated the cube filter and added a filter after the pump I have not had to deal with the filter at all.

If one does want a filter before the pump I would recommend something much larger than the cube filter, but still with a fair course filter media.

Sun Jul 08, 2018 10:52 pm

i run the late metal canister filters before the pump on all 4 of our vanagons, filters are way cheaper than pumps ;)

Sun Jul 08, 2018 10:56 pm

For the specific purpose of testing if your tank is gunked up, this may be a sound effort.

Ours came stock with only the cubicle filter, but once we put the after-pump canister filter kit on, the fuel pump audibly thanked me. For the most part we don't even notice it now.

VW upgraded the filter system for good reasons I suspect, and I long wondered how the plastic filter would take a rock to its mid-section, too.

Mon Jul 09, 2018 11:05 am

While doing my engine conversion I installed an aftermarket fuel tank, new hoses, pump, filter etc. At idle, the new engine was quieter than the old air cooled 2.0 so it's possible the pump had always had an intermittent quiet cavitation noise at idle and I just hadn't heard it before. However. At other times, the pump would indeed get pretty noisy. So, I deleted the pre pump filter, installed a VW dealership adaptor hose ($$) and a post pump filter. There was no real change in pump noise levels. I re installed the pre pump filter. Again, no difference. Some might argue that the small outlet on the early style fuel tank is the [edit: main] reason why the pump might cavitate (make noise) and indeed debris can get in the tank (possibly even via a failed grommet at an expansion tank) but heated fuel can be a large factor. As the GW article states, a lot of fuel is returned to the tank. As the fuel runs through the hoses in engine bay, it might pick up significant heat from the engine en route back to the tank. On a really hot day, on a long drive, how much hotter does the fuel in tank get? Another factor with pump noise; is the EVAP system in good condition? i.e. is the tank venting properly? (I'd guess that some tanks run around with failing grommets or other seals so that point is mostly moot but on a properly sealed tank, is the charcoal canister or its vent tube clogged?)

If a pre pump filter is not installed, one should be aware that the pump itself has a screen inside to catch any larger debris.

Neil.

Mon Jul 09, 2018 11:39 am

Yep, any time our engine's running rough, we remove the forward fuel line from the pump and clean it with a Q-Tip.

Despite our tank being original and with more miles than a trip to the moon takes -- which we once tried but liftoff failed -- I've yet to find significant blockage in the pump screen.

Mon Jul 09, 2018 12:10 pm

E1 wrote: Yep, any time our engine's running rough, we remove the forward fuel line from the pump and clean it with a Q-Tip.

Despite our tank being original and with more miles than a trip to the moon takes -- which we once tried but liftoff failed -- I've yet to find significant blockage in the pump screen.

I recall walking into a local Vanagon repair shop and watching the owner shake out a customers fuel pump. I couldn't believe the crap that fell out. The van appeared to be quite abused and likely never maintained properly.

I'm sure the info is in this forum, but IIRC, some OE Vanagon gas fuel tanks have a built in screen(s). I don't know which model years have or had that though. My early style replacement tank did not have that screen. The metal plate the supply and return pipes are brazed to may suffice to filter out large bits of "crap". Looking again at my images, I see my notes showing images of both the tank I replaced and new tank. (below). It may be that the OE tank has a similar metal plate setup.

Neil.

inside the early style replacement tank

inside the tank I replaced. (Yes, in hindsight it was a perfectly fine tank. I'm not certain it was original though)