Engine Cuts Out

[redboxerk9]

I'm based in Croydon. Temp guage doesn't give us any reading at all.

Right, we know there is definitely a flat spot in the carb as it skips a bit when going into second gear. The cutting out started shortly after having the exhaust put on. There is no warning, it just stalls and we cruise along until we reach a safe spot to park. Immediately after we switch on the engine - it turns over and sometimes (not always) starts up again you have to really rev it up to keep it going. Leave it for a couple of hours to cool down and it starts up again fine. It was whilst looking at it yesterday we had it running for about 5 mins max and when took the cap off the main water tank thing that we noticed the water was very hot, spat out the cap and steamed.

Before we had the exhaust put on it ran pretty well, apart from the occasional backfire due to the holey exhaust and that flat spot on carb, you did have to work it a bit but it ran smoothly on motorways and engine didn't die at all. Although did use a lot of fuel.

I've been trawling thro the haynes manual, the fault finder at the back says two things that we haven't checked for; vacuum leak in the inlet manifold or associated hoses or the idle cut-off valve on carb but would either of these cause the water to heat that excessively. Vacuum leak in the manifold seems the most obvious if putting on the exhaust has disturbed or broken something. And i got the same response from my brother about the carb saying it would just cut the engine like that.

Unfortunately most of the people I know have experience with Aircooled, and i chose the watercooled because apparently they're better fuel economy wise and easier to drive. The later models would have been too hard for me to steer

Hope this is a bit more info, I'll get some photos on tomorrow evening, hopefully this may help

Cheers
Sue

[syncrosimon]

The water system will get very hot, it runs at around 88 deg Celsius, which is not far from boiling point. when the system gets hot, it creates pressure, this will be released when you open the cap on top of the main expansion vessel. This is perfectly normal, and should only be of concern if if the pressure is too high, in which case it will blow excess water through the pipe in the top of the cap into the top up tank behind the number plate.

You are at risk of scalding if you open up that cap, and you just don't need to do it hot.

Haynes is a good place to start, and be methodical, and work through all the areas.

The carbs have complex vacuum operated diaphrams which do various things to make them run more smoothly. They are usually in need of attention.

When this is resolved you will have learnt a lot about your van, which in turn will help prevent future problems. Good luck!!

Sometimes the ignition coil can be sensitive to heat, and be tempremental.

[redboxerk9]

But should the water be getting that hot so quickly, 5 mins running on idle and the water was scalding.

[clartsonly]

dont believe the garage when they say everything is spot on, perhaps it is spot on according to them but not according to your van, ask someone whos hobby it is to adjust these things they will know when the Van is happy with the settings, sometimes "by the book" doesn't suit all 25 year old vehicles.

it all seems too "as soon as it is warm the electics are failing" to me.

there are not that many components and the most expensive is the coil, unless you dizzy is broken.

leads, cap, rotor arm, plugs and timing even without a strobe you can tell if the engine is more comfortable running timed slightly differently, of course unless it is the LT lead or the coil I would assume it would just misfire a bit if a single lead had gone.

if it turns over well enough after it stops working (and you can smell petrol where it is flooding), I am sure it must be spark based. unless perhaps the choke is jammed open and as soon as it is warm enough the choke isn't closing.

get someone to remove a spark plug and check for a spark when it has stopped after being warm.

[redboxerk9]

Managed to find a local VW mechanic with a fair bit of knowledge, and willing to share.

He said to look at the idle cut off valve as if this is faulty it will overheat the van and stop the engine. So we're having a look this evening, and will let you all know.

Do appreciate all your suggestions

Sue

[redboxerk9]

Toomanytoys (Si) came over on Sunday and spent many hours trying to find the solution to this problem. Which was appearing a strange one. At the last hour, my sister came down with her beetle and after the camper breaking down up the road and refusing to start again, Si swapped the rotary arm with the one on her beetle and it fired up straight away. So today have been to Halfords who put us in touch with a VW garage and they have ordered one which we can pick up later this afternoon. So fingers crossed the problem may have been solved.

Thank you so much Si for all your knowledge, it has helped us a great deal and will look forward to meeting you at some of the meetings. Hope you get your bike fixed - someone at my brothers bike club may be able to help (I typeset their magazine) www.kamg.org.uk.

Once again thanks for everyones input much appreciated.

[toomanytoys]

Just had a text, that the rotor arm change seems to have cured the problem.. so one for the wiki I reckon...
If all else checks out and you cant see any reason for a fail.. change the rotor arm... they have a resistor inside and it must be breaking down when hot, but seems to work when cold.... very odd........