Right, well, erm … with some help from graham I worked out why the engine wasn’t firing
It turns out that the float height was set bang on, but when I finally re-assembled everything I put the float in upside down. Easily done as it’s not readily apparent which way is up, but it meant that the little tab that’s normally pointing in towards the needle valve was actually pointing out and jamming up against the float chamber wall, stopping the float from going up and down. This caused the carb to just flood if you kept cranking Took the top plate off the carb, flipped the float round and then re-checked the float heights with the verniers…
Put everything back together, turned the key and it fired after a couple of goes Rough as a badger’s whatnot, mind, but it still fired The little red glows underneath each plug lead, by the way, are the inline spark testers that I’d had on to make sure it wasn’t a lack of spark causing the problems.
I then spent a thoroughly satisfying afternoon under the bonnet adjusting the idle on the carb as per the guides.
Everything’s running a lot smoother now, but things still aren’t perfect yet – but hey, I’m not going to become a tuning expert with one afternoon’s twiddling am I? The idle is now stable at around 800 rpm, but to achieve that I’ve had to “augment” the throttle stop lever slightly with a little plastic hat, as the idle speed adjustment screw simply won’t go far enough in to make contact with the bare lever. Anyone got any ideas how I can fix that?
Went out for a test drive and it feels smoother on the road now and much less clattery too. I’ve no doubt I could spend a whole week tinkering to get it “just right”, but the chances of me doing that by guesswork are pretty slim, so I’ll get it “near enough” for the moment, then find some time to get it down to the local carb place of good repute.
I’ve still got to set up the auto choke side of things too, as that’s way off, but at least I know where the adjusting screw for that is now too
DarthVader: Converting to manual choke is money well spent in my opinion, i can never get those autochokes to work properly
Dave: Despite the awful reputation they gained, based I think on the very early attempts, I have never had any trouble with them. In fact, I think they are pretty good.
me: Can’t say the auto choke’s given me much grief either, to be honest … most problems starting the thing have been down to other stuff, mainly a knackered old battery that I’ve been keeping going far beyond its natural life That excuse won’t wash no more however, as I bit the bullet last week and bought a brand spanking new one and even better – it looks nice It’s got a snorting great bull on the front, so how can it possibly ever let me down ? 60Ah, 570 CCA and fifty quid are the magic numbers apparently. It’s longer than the old one, so I had to move the alarm siren further back on the battery tray to fit it in, so took the opportunity to tidy the tray up with the brass brush in the drill, then gave it some primer and a few coats of blue. Amazingly, I did the whole thing without taking any pictures, so you’ll just have to use your collective imaginations