Hello Got my hands on a Pierburg Zenith 2B5, it came from a Audi 80 1,6 Formel E. That engine delivered 87hp, and the main difference is the carburettor. So hoping for some extra spice on my 1,8 So after finding the rigth flange/gasket to bolt it to the manifold i got the engine started, but it won`t idle. It won`t keep running unless i pump on throttle.. One question is where the wire from Nr.34 goes?, it is some kind of valve. Tried giving it power and it makes a clicking sound, like it`s closing/opening. Anyone out there with a tip? Pardon my English, i`m Norwegian
Don't apologise for your English, it is perfect! That #34 looks like an idle fuel cut-off valve, so will need +12V when the ignition is on, and a ground connection. The polarity (+/-) may be important as there is possibly a diode inside it. It will probably be marked + & - if that is true. So you need to find another wire that is at battery voltage when the ignition is on. What confuses me is your idea that this carburettor will give your engine more power; isn't the output of the GU engine normally 90 BHP? Which carburettor was on the engine before, 2e2? I guess if that was giving trouble I can understand, and if it was that type, the wire that went to the part-throttle channel heater might be ideal for your purpose. I can't see an equivalent heater on this carb. Actually, I've just re-read that this 2B5 came from a 1.6 engine, so you may get some gains (see the thread about re-jetting 2e2s). I'll have to look at my Pierburg book to see what the characteristics of the 2B5 are on that Audi. Edit: Is the 2B5 carburettor you have stamped with part number 049 129 017H? Is your car manual transmission? There might be a problem with the vacuum connections, as a diagram I'm looking at (for VW/Audi 2B5 applications) has two vacuum hoses coming from the vacuum advance unit on the distributor, I don't know why. I can scan/pdf some info for you if you PM me an e-mail address.
Thank you I found two +12v among the wires going to the original carb, the ones that goes to the TTV and another solenoid/valve thing, and the one going to the manifold heater, but i guess i need the last one.. As you stated later on, the 2B5 is a bigger carburettor than the 2E2 that i currently have. Audi also put them on 5sylinder versions aswell, so there should be some gain.. I hope Which one is that? The one under the waxstat? I can`t find that number on it, only AU127 2, and Pierburg Zenith 2B I have a manual yes I would be great if you could E-mail me some info yes Btsoerheim at hotmail.com
Actually, the one I've highlighted in bold may be the best/easiest. It is polarised (the connector only fits onto the 2E2 over-run cut-off solenoid one way) and may fit directly onto the idle fuel cut-off valve on your 2B5. The wires may not reach, but you could extend them. Can you see any "+"/"-" markings on the valve? If not, and the connector on the valve is symmetrical, then the plug that used to go to the 2e2's TTV would probably fit, and do the job. Make sure the wire that used to go to the part-throttle channel heater (near to waxstat on 2e2) is well insulated because that is an unfused +12V and you don't want it to short-circuit to chassis/earth. Same applies to any other wires that are no longer used. I'm about to e-mail you some scans showing the relative barrel/venturi/jet sizes on the two carburettors. Your fuelling is likely to be rich, I think; good for power, bad for economy. Only a run on a rolling road will really show you what your new air/fuel ratios are like (and I would advise you to do this, to check that things aren't going lean at any point). I'm confused about the extra vacuum connection shown in the diagram I'm also sending to you. With luck you won't have any left-over vacuum hoses...
I forgot to check the valve for markings But first thing tomorrow morning I`ve been digesting some of your older threads/post, and among them i found a warning for this unfused +12v, so i think i`m gonna install a inline fuse on, just in case. After getting it to run "properly" i`ll have to get it adjusted. There is a company here where i live that specializes in carburettors, so i`ll give them a visit Thank you very very much Pete [>:d<]
