Hello all I've been faffing about trying to get one of these to play nicely with my 1.8 auto GL. The car looks like it had been stood for a few years when I bought it, but it did drive alright. 1 year later, after some restoration work I'm now trying to get it back on the road and back in Weber Woe-ville. I've got 3 old/used carbs from my hoard pile and noticed two different types of idle mixture screw. One is kind of 'stepped' and the other a smooth cone. Does anybody know which one is correct, or if either is OK? I'm currently trying with this type of stepped mixture screw which was already in the carb that runs best so far. But I found this kind in another of the old carbs I've gone through everything I can think of: Replaced both pump diaphragms - one under 3-screw cover on the side and one under 4-screw cover on the front new rubber flange / mount - and wobbling the carb while running doesn't have any affect so seems OK all jets and related tubes/parts are correct according to spec for a 1.8 If I block the vac advance pipe to dizzy it seems to 'smooth out' the idle a bit new air filter new fuel filter (before swirl pot) The side pump diaphragm was visibly damaged which gave me hope, but after replacing with a new one I still can't lean it out fully. The car runs but seems really rich and turning the mixture screw all the way in doesn't kill the engine, which to me indicates it's not doing it's job properly (afaik this should lean out the mixture so much that the engine can't run). It seems happiest at about 1 - 1.25 turns out from 'fully lean' - but still smells rich and has sooty exhaust output. I've booked in a RR session at Motoscope in a couple of weeks - but would ideally like to drive the car up (~1.5hr drive) instead of transporting it. Cheers
I ended up buying a brand new 32/34 - pricey but at least should rule out the carb being the issue. At least until I read a post somewhere that new Webers sometimes have slightly sticky throttle linkage - fixed with a drop or two of light oil. The new carb has the 'pointy' / not-stepped mixture screw. Got it happy enough to drive around but still suffering from: backfires when turning off with engine up to temp. This happened when I pulled into a petrol station forecourt which got a few comments sometimes 'runs on' when ign turned off with engine up to temp sometimes stalls when pulling away from idle, have to be slightly careful / gentle with the throttle The plugs were pretty sooty / fouled, I assume from lots of idling / setting carb up so I cleaned them up - next step is to take it for a motorway blast to try and de-coke the cylinders in case that's causing issues. I don't want to run it too lean though so erring rich on the side of caution. Have seen people talking about dribbling / misting water into the carb while holding revs at around 2k to help de-coke the cylinders, but others claiming this is risky - something about hyrdo-locking the engine - so not tried this yet. Compression test seems OK to me - approx readings for cylinders 1-4: 160, 170, 165, 160
