Technical 1970 F500 Power Loss

[onetwopi]

Hello and Happy Thanksgiving to the Americans!

1970 Fiat 500 499cc

Had it running quite well, would top out at 75-80 kph and accelerate reasonably through the gears. But somewhat suddenly, I accelerate unbelievably slowly and top out at 45-50 kph. Any ideas of where to start troubleshooting?

Mike

 

[fiat500]

Hello and Happy Thanksgiving to the Americans!

1970 Fiat 500 499cc

Had it running quite well, would top out at 75-80 kph and accelerate reasonably through the gears. But somewhat suddenly, I accelerate unbelievably slowly and top out at 45-50 kph. Any ideas of where to start troubleshooting?

Mike

Plug lead fallen off or got burned on the exhaust?
Accelerator cable slipped loose at the carb?

 

[StMarks]

Hello and Happy Thanksgiving to the Americans!

1970 Fiat 500 499cc

Had it running quite well, would top out at 75-80 kph and accelerate reasonably through the gears. But somewhat suddenly, I accelerate unbelievably slowly and top out at 45-50 kph. Any ideas of where to start troubleshooting?

Mike

Is it running ok at tickover.?
If not, then perhaps running on 1x cylinder as suggested above.
I'm thinking that it could also be a blown head gasket, blocked exhaust, or any number of things.
If the engine seems to be fine on tickover, and revs up ok at standstill, perhaps it could be drivetrain related & nothing to do with the engine (could even be the brakes be binding, perhaps try rolling it by hand).