engine and drivetrain Help with Weber 32/36

[jpcapoc]

Hello, first time post for me. Looking for help with a problem. I installed a 32/36 on my 1970 2002. It's always been hard to start, seems like it's flooding. I've also been perplexed that my gas mileage is only 18-20 mpg, I expected better. I think I now know what's causing the problem, but I don't know what to do to fix it. When checking the timing the other day, I noticed gas dripping from the auxiliary venturi iwhen idling at 1400 RPM. I'm assuming that it's "pushed", because if it was "pulled" via normal vacuum, it wouldn't be dripping. It wasn't doing this at normal idle RPM, at least I couldn't detect it. When I shut the engine off, then the dripping resumed. I've also noticed that if I shut the engine off and start it immediately, the car starts fine. That makes sense to me, because it hasn't had a chance to flood. I'm thinking that the problem could be one of two things. Maybe my pressure is too high? It's a stock fuel pump. Could it be that the fuel is getting too hot? I suspect that my water choke lines may be too close to the fuel line and heating the fuel and causing too much vapor pressure. I've checked the float level, it's dead on, and I even replaced the fuel inlet needle valve -no difference. Any suggestions?

[SteveH]

Float level? http://www.bmw2002faq.com/content/view/62/33/

[jpcapoc]

Float is fine. Checked and Rechecked!

[Chris_B]

Odds are that your needle valve is FUBAR. Buy a rebuild kit and have at it.

[mikem]

If the vent(s) is plugged, pressure could be building up.

[Guest Anonymous]

Thanks, where is the vent? I'll check it.

[mikem]

Should be in the trunk, the rubber filler neck has a plastic hose/pipe that should run somewhere. I don't know the specifics of a 1970's vent system.

This may or may not be representative:

http://www.realoem.com/bmw/showparts.do?model=2552&mospid=47140&btnr=16_0386&hg=16&fg=05

[Guest Anonymous]

Got it. Thanks. I blew compressed air through it. It's fine. I'm going to go ahead and reroute my water choke lines away from the fuel line. Hopefully that's the problem.

[Benetton]

sounds alot like my problem, float level dead on, but gas is leaking. Do you get a collection of the gas on the intake manifold? sometimes i do, i still havent figured out whats wrong.now that i think of it, i think all this started to happen when i switched away from my vacuum adavnce dizzy to a tii unit.

[jpcapoc]

I can't see gas accumulating on the manifold, it was just dripping from the auxilary venturi that's in the middle of the main venturi. It was just dripping on the primary side, not the secondary, which I don't understand. Seems like it should have been pushing from both sides if there was internal pressure.

Anyway, I installed a cheap adjustable pressure regulator today, rerouted my choke hoses and so far so good. The weber manual says maximum 3.5 PSI, but it would cut out at high RPM at 3.5. I set it to 4, and it's better, but it seems just a little bit weak over 5K rpm, but at least it doesn't cut out and no gas dripping after my test run. Still doesn't start right up cleanly on the first try, but maybe there's something else I need to adjust, or maybe my expectations are just too high.

I tried a 55 idle jet, but it's too lean, according to the Redline Weber adjustment procedure, so I went back to the 60. Other than the minor starting issue, it's running really sweet.