I’ve replaced the accelerator pump membrane which was leaking and the fuel enrichment valve while I was at it. And the lambda voltage at idle, with the engine fully warmed up, is quite high, 0.98V. Should I adjust the fuel mixture screw?
If you're 100% sure the carb is tip top, that would be the next step. if you check my signature link I have the haynes 2e2 carb manual printed out, which goes into a lot more detail on checking over all the internal carb adjustments so have a look there too
Have you checked the vertical air-entry slot in the side of the tube that sits over the idle emulsion tube? If that's blocked up the mixture will go rich, I think. I think early carbs had two separate holes rather than a slot. It's on the side facing the primary barrel, so difficult to see without removing the tube.
Well. I completely took the tube off with the mixture screw inside it and I still had a high lambda value of 0.95-96 V. The slot in the tube is fairly clean, definitely not clogged. Could it be the fact that I haven’t hooked up the solenoids for the 3 point unit?
Those would just mess up the idle and over-run control, fully extended is engine off/first start high idle, fully retracted.over-run and you have 1 or 2 running positions depending if it's a 3 or 4 point. Won't affect your mixture anyway, just the engine speed. If you haven't got it connected to anything it'll just be stuck fully out all the time, and your revs stuck at 1500-2k rpm. If someone has.messed with the internals to make it idle like that then you need my Haynes pdf to reset.it all
I see that under the diagnostic section it mentions heavy fuel consumption caused by “leaking power valve diaphragm” (does this refer to the part throttle enrichment diaphragm?) and it also mentions an o-ring seal (I have no idea about that).
Not sure but assume either the accelerator pump or the part throttle enrichment, might be worth getting a full carb gasket set part number 027129281
I already have a complete gasket set and I’ve even mentioned in one of the previous posts that I’ve replaced the accelerator pump membrane, the enrichment valve and the main top half gasket (this one was replaced more recently), especially because two of them were put on there and I had a leak.
Power valve = part throttle enrichment valve, yes. It's all lost in the mists of time and probably before I started taking photos of things, but the o-ring is a tiny one that the valve seats against, I seem to remember. Wasn't that part of the enrichment valve refurb kit? Was it a fully assembled new valve you bought like this? O-ring is arrowed: https://www.dropbox.com/s/tk0i5d9l7kzsmqs/Screenshot 2021-06-14 09.42.46.png?dl=0 Main carb gaskets have been known to have missing holes, or ones that don't align properly, did you take any photos while fitting?
Yes, it was fully assembled. Sadly I didn’t take any photos of the main gasket, the holes seemed to align pretty well. I think I’ll take it apart again and take some photos. Also forgot to mention that there is a hole in the top cover and I can see the float chamber through it, on the old 2E-E there was some sort o mesh there. I’ve marked them with green circles.
It looks like there should be a mesh, probably part of a clip-in plastic fitting, judging from this photo I just found (zoom in): https://www.dropbox.com/s/tqtax74k6zd93nn/Darren2.jpg?dl=0
I haven’t done anything on the car, yet, but someone suggested me to check the second stage throttle plate. Any ideas on how I can check the adjustment? Can it cause the high fuel consumption?
You can check if it's free to move with vacuum by putting a longer vacuum hose onto the 2nd stage vacuum unit and sucking on that while holding the 1st stage throttle wide open with the cable. They can get stuck closed, that might make the mixture go a bit crazy.
I have driven the car for a while and replacing the gaskets made a little bit of a difference, but I think the problem might be related to something else. I'm having quite major fuel evaporation issues and these issues worsened when the temperatures outside started to climb. On a warm engine, after about 10 minutes, most of the fuel evaporates and I have to crank quite a bit until it starts and the hotter it is outside, the higher my idle is. Also, I've noticed the AFR got worse after I connected the coolant hoses for the choke and wax stat. Could it be that my engine runs richer just because of fuel vapours? Oh and the second stage works perfectly fine.
Yep that's the one, just a thought. I remember back in the day I bridged my thermoswitch as it was broken, and the car ran worse when warm like that