Just new to the VW seen,ive got a 1977 bay with a 2 litre motor in it ,the problem is ,it will tick over all day and never miss a beat,but when you rev it up to 1500 revs and above,it spits back through the carbs and trys to cut out. Its got new heads on it ,new coil,spark plugs and leads,rotor arm and dizy cap,electronic ignition fitted,its running on newish webber 34 ict twin carbs,tappets ,spark plugs are all set correctly and the timing to 7 degrees ,ive checked for air leaks and carnt find any. Can someone please help im lost with it now dont know what else to look for.
Check it is fuelling correctly. Also check tappets are set right. On Saturday there was talk about the wonders of the T4 engine. Can idle fine and fool you but try driving it when it has a fault and it will let you know.
sounds similar to when mine was leaking air. Mechanic told me a neat trick to locating the problem (if it is air) He sprayed carb cleaner around the air intake when running. It revved up really high through the leak.
Thanks for the tips ,i tried the wd40 trick and nothing happened ,but ill try the carb cleaner trick,doz anyone know wich is the best electric fuel pump for one of these,it was on a origional mechanical,fitted a electric one but dont know if its up to the job.Its spitting flames back through the carbs.
Have you fitted the fuel regulator with the new pump as it could be pumping too much fuel causing blow back through carbs?
Facet pumps are pretty good for what you need. Try the link to the Coolair web page. http://www.coolairvw.co.uk/Item/NA/AC127200/Facet_Electric_Fuel_Pump_-_Reproduction.html
Just my two pennyworth........ (not that its worth much) Have you got an auto box? If so, my thinking is your timing is off, I had exactly the same problems with my 1700 auto it would cough and splutter and fire back through the carbs..... and then found out that the auto boxes should be timed to 10 degrees and not 7.5. Just try advancing it a little bit and see if that helps out anyway.
Webber 34 ict needs fuel pressure regulator or they can over fuel are u sure its jetted correctly? It might be set up mixture wise but if jetting wrong it will not run right at all.
I've got stock carbs and know nothing about Webers, but mine runs quite rough if the carbs aren't balanced right. Sounds like it's running on only 3 cylinders.
I have the same problem - on a CB code 1700. Was thinking it's a weak mixture thing - opening up the fuel regulator seemed to help - Opening the mixture screw (Weber 32/36 carb) seemed to help - WD 40 spray did not show up an air leak. BUT It still wont stop spitting back thru carb on slight throttle. If you ever find out a cause - let me know.
Are you running a 009 distributor? These can cause this! also a broken or weak advance spring, Have the advance curve checked with a timing light, T4 also hate being to lean look to around 4% co.
