Did you try new fuel filters? Did you get the fuel system checked for flow and pressure?
How many miles? At this age you would be checking all the air hoses and fuel lines for cracks and leaks. Also it wouldn't be unreasonable to rebuild the carb.
I have a problem with the engine on my 1.0L Samurai with carburettor.
1. Sometimes after driving, engine won't start easily again after some time.
2. It has happened 2 times now that the engine suddenly shut off while driving. It would then hesitate to start again (like previous problem). Engine was already at normal temp.
3. It has happened a few times that when turning on the engine it started normally, but when put in gear (reverse) with clutch depressed, it just shut off even before releasing the clutch. In other words, engine shut off immediately when the stick locked into reverse position.
Anyone know what may cause these problems?