Running/fuel problem

[Devonboy]

Hi, wondered if anyone could help I've got a 2ltr air cooiled engine that is running poorly. It starts fine but I have to keep revs up to stop engine cutting out. When I try to drive I have very little power engine feels like its missing and not pulling,wont let me drive up hill due to lack off power. After spluttering along for several miles the engine seems to pick up the van drives ok, but the van stinks of fuel. I've noticed the back of the van is covered In fuel and when I put hand in front of exhaust it's covered in petrol. Not a mechanic but obvious not all fuel being burnt any ideas would be much appreciated, many thanks Ian (

[BOXY]

Have you checked to see if each of the plugs is firing?

[Devonboy]

Thanks Boxy will try plugs

[poops1966]

I have a similar problem but no apparent fuel leak, has been suggested I look at the auto chokes, is your an auto choke?

[Devonboy]

Yes mine are auto chokes just had plugs out black and very wet with petrol have taken carbs apart
To try new needle valves. Floats look okay but I'm sure that the problem is access feul flooding plugs and coming out of exhaust. Hope this fixes problem if not will look at chokes let you know what happens thanks for your input

[BOXY]

If the van has got the original Solex carbs fitted it will have an auto-choke on each. There should be a spade connector that supplies 12v + when the ignition is switched on. This supply heats up the bi-metallic strip which gradually opens the choke (turns it off) over about 5 minutes. You can check the chokes easily. First take off the air box with the engine cold and check to see if the choke flaps are closing off the barrel of the carb. Then switch on the ignition and watch the carbs. The flap should slowly turn to the upright position. You can check the 12v supply at the same time.

If the chokes aren't coming off they could be flooding the engine once it's warm. Equally if a part of the ignition system is causing a plug or two to misfire that could lead to the same symptoms. All that's required to check the plugs is a spare spark plug, no tools required. Pull off one of the HT leads, connect to the spare plug and rest the plug against the block. Get someone to turn the engine over and you should see a spark. The engine will probably even start and run on three cylinders. Repeat the process for each spark plug. If they're all sparking then fuel problems could be the answer.

[Devonboy]

Thanks buddy

[Devonboy]

Still haven't managed to get to the bottom of the problem have been told maybe the valves to be sticking or broke would this sound right how can I check do I have to take the head of the engine Any input greatly appreciated thanks

[CovKid]

Do a compression test. If cylinders check out ok, user Sarran has a video on tuning twin carb engines.

[BOXY]

WHS ^^^^

Where abouts are you based? I can't see how a valve problem would cause the fuel out of the exhaust though. If the plugs are firing and the fuel mix is right it should still ignite whether the valves are sealing of not. If the inlet wasn't closing you would get obvious "popping" out the carb with the air filter off, and maybe even some blue flames! If the exhaust valve wasn't sealing you'd get "popping" out the exhaust as the petrol air mix burnt in the exhaust. My money is still on a electrical / ignition problem.

[sarran1955]

Do a compression test. If cylinders check out ok, user Sarran has a video on tuning twin carb engines.

Hello,

Engine needs setting up

here is the first video,

http://www.youtube.com/watch?v=4qayyc9Z4E0

Then there is part 2.

As has been said, compression test and oil pressure test and results please.

Pictures will help, general engine view, left hand side of engine bay, view behind air cleaner...

You will be changing perished rubber hoses, and learning about tow to diagnose air leaks next

Don't worry... It's a VW thing...

Cordialement,

[Devonboy]

Thanks again guys for your input going to get a mechanic to have a look over it for me will let you know how things pan out thanks again

[Devonboy]

Cleaned carbs new gaskets needle flouts new plugs fuel regulator all fitted van ran lovely took it for a 30 mile run no props stopped went for a surf came back restarted van after about three hours and It's now started to cut out on me the engine starts fine ticks over okay you put foot down on accelerator and it pops a little bit out of the exhaust Take off Excelerator revs die back and engine dies out having a nightmare

[lefty67]

have you checked all the vacuum pipes from the carbs and air box for any splits or to see if one has come off?

[BOXY]

Have you got a timing light to check the timing? Check to see if the dizzie clamp is tight? If you're near Plymouth I might be able to take a look at it?