fueling issues

[scatman]

i've got a 1.8 mk2 scirocco that judders and then cuts out randomly on longer trips, usually over 20 minutes but occasionally does happen after a few minutes. i reckon its due to rust/crud in the fuel line.
i know the filler necks can be an issue and can be sourced from vwheritage/ebay etc but i am unable to find a replacement swirl pot. i reckon this is the source of the problem but at the moment don't now a way to solve it (i was hoping to clean the pot but upon futher inspection i've noticed its a solid unit )

is it possible to by pass the swirl pot with no adverse effects? or does any one now where i could get my hands on a new swirl pot?

[Blueshark]

https://www.vwheritage.com/search/?act= ... btnSearch=

[scatman]

Sorry, I should of mentioned it's a carbed engine and the pot looks cylindrical with two pipes on the side and one coming out of the top

[GTXTRA]

worth a read.

viewtopic.php?f=12&t=18499

[bengould]

You can replace the swirl pot with a simple t-piece connector to test if it is causing an issue. Long term it's probably better to keep it though.

With that in mind though, when my car still had its carb I had done this and placed a small restrictor, 0.8mm welding tip, in the return side of the t-piece. Worked fine for me for several years.

Ben

[james butler]

You mean this?
http://pages.ebay.com/link/?nav=item.vi ... ID=EBAY-GB

[scatman]

I do yes, thank you. That is exactly the part I'm after. However I know no its not the sole cause of issue. I replaced the fuel filter today and examined the old one. It was full of little bits of crud. So I removed the fuel pick up unit and had a look in the tank. This is what I saw:

There where some bigger bits of debrie in there as well. So I'm definitely going to need a new fuel filler neck (as the tank looks to be In good knick)

Also how accurate are the fuel gauges, as that seems to be quite a bit if fuel in there but the needle in the red and it moves drastically even when driving normal, or when stopping at lights

[bengould]

Also how accurate are the fuel gauges, as that seems to be quite a bit if fuel in there but the needle in the red and it moves drastically even when driving normal, or when stopping at lights

Not very.

I have had mine below the red before and never ran out of fuel. Not recommended though as that is when you're more likely to suck the rusty bits up.

Stick a strong magnet in the tank a few inches away from where the pickup is and that will start to catch the bits in the tank. Remove it every now and again to pick the bits off.

Ultimately you are going to need a new filler neck, or if you can weld take yours off and repair it. I did mine not long ago and sealed it with a fuel proof epoxy mastic paint. It's like a new one now, and pretty much for free. We have sheet metal and paint handy at the moment for our T25 restoration. .

Ben.

[GTXTRA]

Agreed - Magnets and a new filler neck - you can heat up a plastic filler neck from a BMW E36 and make it fit too if you can't find a steel one.

[scatman]

has any one tired fitting some fine wire mesh to act a filter between the bottom of the filler neck and the rubber hose is connects to? in theory this should catch all rust debris that would get stuck in the fuel pick up and any thing small enough to get through the pick up should be caught by the fuel filter. with regular checking of the fine mesh, should provide a semi permant fix.

what do you guys think?

[bengould]

http://www.justkampers.com/111-209-147- ... -1974.html

I used to use one of those over the end of the brown pickup pipe on the sender.

If you chop the bottom bit off just above the seam it fits perfectly over the wider section at the end of the pickup. Secure it with a cable tie.

The standard pickup just has 12 holes drilled into it which quite easily get blocked by rust. This gives you a much bigger surface area to take fuel from and also much smaller holes to stop most of the rust in the tank getting past.

Ben.

[james butler]

i know this probably sounds counter intuitive but i fitted two filters to mine and deliberately ran it low on fuel so it sucked all the crud up into the first and second filters and kept replacing them weekly untill no more crud was found in the first filter.
granted magnets are a good idea but it doesnt remove the rust from your tank either.

[scrappy1382]

but i fitted two filters to mine and deliberately ran it low on fuel so it sucked all the crud up into the first and second filters and kept replacing them weekly untill no more crud was found in the first filter

funny that, its exactly the same as to what i done in my gt2

[scatman]

so i replaced the vapor pot today, very simple straight forwards swap. only visible difference between the old and new one is that the top line comes out higher, which slightly effect the air box bracket.

i decided to cut open the old one to see if had made the right call in replacing it. saw something i didn't expect to see.....




the shiney bits are metal which came from hack-sawing it open. what suprised is the sand like substance. you can see it quite clearly in the pictures, i have no idea what it is or where it come from. Any of you guys know or have any theories?

On the rust filler neck issue, i'm currently investigating the possibility of having a silicon pipe inserted the entire length of the neck. if the tubing i'm looking at is the right diameter and flexible enough. what i would do would be to fit it in the filler neck, block the gap between the filler neck and the tube so rust cant physically enter the fuel tank (the tube would be slightly protruding from the neck). the top of the pipe would be flush or very close to the petrol cap so the fuel shouldnt come in contact with the filler neck what so ever. i would drill a small hole at the bottom of the filler neck for any dribbles of fuel that might flow down it.

this should be a good permant solution that will be cheaper than buying a repo one at £150+ and save the hassle of welding a golf one.

[mark1gls]

The filler neck only needs a small hole for dirt and water to get onto the fuel system, as you know it's under the wheel arch and every thing on the road is throw against it and looking at yours sand has got in and the fuel filter has let it through. It is an important job to keep an eye on and clean/protect the filler neck.
It a pain the mk2 filler neck is an expensive item when the mk1 golf ones can be bought for £30, I did replace my mk1 golf cabriolet one which is different from a tin top golf and that was £70 so I painted with epoxy mastic, stone chip paint and Hammerite then waxoyled it, I clean out under there with a hose every 4 months or so and spray a little waxoyl under there before each winter as it is my daily drive and 10 years later it still looks fine. The car is off the road at the moment for an engine swop so I plan to remove the filler neck to double check it just in case as sand and fine grit will kill my fuel injection system as there's a lot more stuff to clean and expensive bits to replace than a carb car.
Plastic or stainless steel is a good idea but you can make a standard one last if treated and looked after and not fitted and forgotten about.