Scirocco Register

Hello everybody,

I have finally got a fresh ticket on my 1978 GLS, it has been off the road since 2008 and i have been very much enjoying driving it around again!

Before it went for MOT I had a guy out who knew his stuff and got him to get the car idling and running properly, and all seemed well.

Since having the car back on the road it has developed an exciting habit of starting up fine and beginning a journey with no problems, then the car will start backfiring and then eventually stall. After this has happened the car won't idle, it will fire up but then stop and is un-driveable for around five minutes. After waiting for a bit you can start the car and drive about half a mile further down the road before the process starts again! Suffice to say i'm not planning any long haul trips any time soon!

The car has had recent plugs and leads, new points, condenser, distributor cap, rotor arm and coil. After i changed condenser, points, rotor arm and cap i managed to drive a little further but then it happened again so i put a new coil on yesterday and the problem has persisted.

At the moment i'm thinking it could be something to do with the autochoke but i may be well wide of the mark, it is still equipped with the original carb.

Any thoughts?

Cheers!

What is your fuel tank like? Have you changed the in-line filter? The carb flange okay?
Sounds like a fueling issue.

Yes, I changed the inline filter the first time the problem happened, and i put a new carb flange on before the mot so that's only about a month old.

I thought fuel the first time it happened but when it started happening after the filter change i switched to ignition with no luck!

What about the fuel lines in the engine bay, they could be collapsing under load, not unheard of?

Hi just to resurrect this one a little. I thought I had a solution to this having cleaned through the idle jets in the top of the carb. (I was told it was either the jets or the start stop solenoid) Problem went away for a while, then one day after putting some fuel in it came back with evengence and made a 20 minute drive last over 2 hours! The car essentially behaves as if it has run out of fuel, I have since replaced the in line filter again and fitted a new manual fuel pump! When coming back from an mot the car stalled again and the mechanic was cursing me for not putting enough fuel in! I am now sorely tempted to fit a weber carb in the hope that it will be easier to maintain reliability. Of course my wife was in the car during this lengthy trip in the rain and has lost any enthusiasm for classic car ownership!

Any thoughts would be grand, i.e. where to source the weber carb, I seem to be able to find plenty for the later 1595 cc but will this be a suitable replacement for the 1588?

Cheers!

1; Check your filler neck. If its even slightly rusty clean it, wire brush or paint/rust remover on an angle grinder, and either repair or replace it.

2; Check inside your tank. If there are bits in it, even if you can only see a few, either drop a magnet in or ideally remove and thoroughly rinse out the inside of the tank.

3; Replace the hard fuel lines under the car. Originals are steel and will rust, I used kunifer lines of a slightly larger diameter but anything 6mm I.D. will be fine.

4; Replace all rubber fuel hoses, both in the engine bay and the ones from the sender to the hard lines under the car.

5; If your car has one (I'm not sure if mk1's did) replace the swirl pot in the engine bay.

6; Clean the carb again.

7; New fuel filter.

I would do all of this before going down the weber route. 1; its cheaper and 2; if it is being caused by rust or anything else in the fuel system, it will still do the same with any other carb. Also, if you can get your pierburg running right, it is a better carb.

The weber for the later 1595cc engines will be fine jetting wise the difference in engine size is not worth worrying about. Only thing I'm not sure about is if the early engine uses the same mount to the manifold as the later engine. If it does all will be fine.

Ring webcon UK if you have any questions about weber carbs, the guys there are VERY helpful.

Hope some of this helps and you get to the bottom of the problem.
Mine annoyed the hell out of me many times before I finally got it going right.

Then I went and swapped the engine for a 20vt which came with a whole new set of issues. Some people never learn. Lol.


Ben

I also have a 1978 Mk1 GLS and I did replace my carb for a webber but it was years ago, I think you will find your car is fitted with a Zenith carb I had to fit a different webber carb I think it was a 32/34 DMTR but will check tonight as I've still got the manual for it.
I called Fastroad cars when I needed help with what bit needed for my carb.
http://www.fastroadcars.co.uk/shop/index.php
Wecon link
http://www.webcon.co.uk/

As already said check inside the tank and look for rust/dirt blocking the fuel pick up.

You want have a swirl pot in the engine bay.

I replace my carb because I had done a repair kit on the Zenith carb then a couple of months later I started getting more problems, mine started running rich, backfiring and the only way to get it to drive was at full throttle which is not useful in traffic, at the time is was my only car so I needed it fix quickly so I fitted a new Webber in 1/2 day and it's been fine for the last 15 years, just a little tune up every now and then.

Did you check the gap on your points with a feeler gauge or a dwell meter? I did find a dwell meter to be more accurate then feeler gauges, I've since changed to electronic ignition and Accuspark kit for £30 and I would recommend the upgrade.

Edit..... Just found some info and which carbs fit...
http://www.webcon.co.uk/Downloads/2008% ... 20kits.pdf

The quality of condensers and points seems to have gone down hill so I would have a look at yours and see if there is any pitting on the points. I found it very hard to get a good brand of them so that's why I gave up and fitted the kit.

Link to thread about fitting the electronic ignition, the hardest bit it getting power to it. (I'm mark1gls on this site as well)

http://vwgolfmk1.org.uk/forum/index.php ... &kfs78=450

Do these cars have the ignition amplifiers? If so, a knackered one can cause exactly this sort of problem.

Given he said he replaced the points, I'd say not.

What brand of condenser and points did you fit?

I can't remember which brand the condenser was, I'd have to check my receipts. Vaguely remember a blue and yellow box!? I used a feeler gauge to set the points so could try the dwell meter on them. The electronic ignition is definitely something I have considered I will look again at the link thanks!

Thanks very much for the responses I will certainly investigate the fuel tank. The filler neck looked better than I expected when it was last away from the car!

Does the zenith carb' use a diaphragm? I ran cars back in the very late 70's (yes i am old...) that suffered similar problems because of a tiny split in the diaphragm.
The other one i had with similar symptoms turned out to be a wire on the low tension side of the ignition. Once things got warm the expansion caused the wire to act as though it was broken.Simple check is the connections at the coil to ensure the spade connectors are still attached to good copper wire!