Cleaning out the fuel system

Hi all,

Has anyone ever cleaned out the fuel system for their Mk1?
Mine's an injection model, Clipper Cabrio '88.

Replaced the fuel filter but only helped for a little while. most obvious would be the fuel pump is struggling to get fuel to the engine, which means it's blocked most likely.
I'll run engine cleaner through and check the fuel filter afterwards but ideally I'd like to clean out the entire fuel system.

Thanks in advance,

Gordon.

Been done a fair bit on these cars

They is a guide in the "how to section" for cleaning out the tank

Check the lift pump in the fuel tank, these are prone to failing, I've been through 5 in my 1988 golf cabriolet. You may be lucky and its the little filter on the end getting blocked, while its out have a good look inside and check for rust etc you can fish some out with a magnet then once the worst is cleared drop the magnet in the tank to pick up the rest while driving about.
They are cheap and easy to get to.

Your car can't be a clipper as they came with a carburettor ?
You do have the fuel injection system if so it's a GTi?

I can't seem to find the "How to section" on fuel systems??… Maybe I'm just been blind!

I'm going to take out the fuel filter first as it's easy, rust might be the answer though as there is a small crack at the top of the fuel tank..

How do I get to the lift pump? I was going to check the fuel accumulator too. Is it necessary to take the fuel pump out and clean it?

It's a 1988 Karmann. One of the first injection clipper kit Mk1's I believe.

Thanks for the responses guys. Just trying to figure out ways to check the fuel system without taking everything off!

 

You really need to fix the filler neck first as you will get water and dirt going back into the fuel tank and you will just be back at square one and more damage and cost to the injection system.
If you look at the bottom of my project thread you can see how I got a tin top filler neck to fit or you can buy a cabriolet one but they are pricey.

http://vwgolfmk1.org.uk/forum/index.php?page=topicview&id=projects%2Fyour-mk1-golfs_2%2Fmy-daily-drive-1988-gti&kfs79=30

To get to the lift pump remove it's under the base of the back seat under a black cover. I'll try and find a link save me typing it all out again.

Found this…
http://vwgolfmk1.org.uk/forum/index.php?page=topicview&id=big-block-injection_2%2Fwonder-if-you-guys-can#post_1345240

If you have a metal top on the lift pump/sender like mine (some are plastic) you need turn it about 45 degrees to remove it, it's like a bayonet connection I use a flat bit of metal to tap it around to undo it. It is an art getting it out as there is the fuel tank level float attached and a pump so there not alot of room to get it out but it is possible just go carefully.

Also found this but you will have a different inside of the fuel tank as that one is from a tin top car and it does not have a lift pump, not fuel lines coming out of the sender and its plastic, a different filter inside the tank but you get the idea of cleaning the fuel tank out.
View topic: Fuel Tank cleaning *HowTo* clear that blockage - The Mk1 Golf Owners Club

You can see the filter in this link to a new lift pump.
http://www.ebay.co.uk/itm/VW-GOLF-MK1-CABRIOLET-MK2-GTI-8v-16v-FUEL-PUMP-LIFT-PUMP-IN-TANK-C246-/200691149226?fits=Model%3AGolf&hash=item2eba1fe9aa:g:VV4AAOSwMzVTw6~7

But rather than taking lots of things apart I'll try narrow down the problem… Correct if these steps are wrong:

1) I'll get some pics of the tank and the neck filler to see for any damage.

2) I'll take the fuel filter out and see how bad it is, although it's fairly new so I don't think this is the problem.

3) If no damage to tank or neck filler, and the fuel filter seems fine then I'll disconnect the fuel pipe from the accumulator to the fuel pump and turn the engine over.
Am I right in thinking that if some not very nice gunk spills out of the fuel pump then I've found my problem?

After this my knowledge on this ends.

nb. What can I use to clean out the fuel lines?

ps. the job you did on our GTI is awesome!

 

You could be surprised how much dirt/rust gets into the fuel filter which is in your engine bay. Its the last filter on the fuel lines. Its always a good job to change these regularly. It will prevent any more issues getting into the fuel injection system.

On my cars I started with dropping the back axle and removing the tank and always ended up changing it due to internal and external surface rust.

The tank is probably 27/28 years old now…

another check is to remove one of the wires from the main pump under the car, then you can hear if the in-tank pump is working.

That is if your car primes the pumps with ignition, if not just swap the 18 relay into slot 2 this will make the fuel pumps come on constant with the ignition so you can listen out for the lifter pump