I have one of those. Exact same specs. I got mine in 1999, got it back on the road in 2000. It had been standing since 1982. But in a garage;) Was struggling with off-the-charts high CO, and engine spluttering/misfiring when idling. Found a faulty fuel pressure regulator, miss-adjusted throttle switch and some bad electrical wires. It was almost good, CO could now be adjusted to correct figures. But still spluttered. Every time I opened the hood and put the CO reader in the exhaust, it ran well with nice readings! But when driving it wasnt. By chance I discovered it stopped spluttering when I opened the bonnet, and started when I closed the bonnet. Bought new HT-leads and a 123 distributor. All well after that. Strange though, as the HT leads are well hidden under the intake manifold. Oh well, been working since.

"Oh well, been working since."

Haven't been back to my friend yet.

This thread made me chuckle. Yes, carbs are so like that haha.

I actually get on pretty well with the injection on my 80's Mercs. Bosch KE-jetronic. It's a bit of an engineering work of art, but even I have managed to fix problems, and have a pretty good understanding of everything that goes on. It's so reliable! Amusingly the carb thing is still more of a pain in the arse. ..

Well one problem was solved. The car now didn't idle. So i cleaned the idle jet. Running but not well turning the mixture screw no reaction. I took it out and to my surprise this had a bend tip??? Replaced it, better but it isn't optimal yet.
The hissing sound turned out to be the generator pully just touching the tins.