Hi,
(Fiat 126 652cc engine fitted in a 1970 Fiat 500. Also posted this on the 126 Forum.)

This car had sat for over a year and it started immediately, although with an erratic idle (kept dying unless foot on accelerator.)

Drove it about 5 miles and it ran OK although it kept cutting out at lights but started again OK.
Then, the next day, driving along about 50mph, it started spluttering and coughing, revs dropped and it cut out.

As I had not tool, I called the AA who removed the carb, cleaned all the jets, put it all back but it just wouldn't start for the AA man so he towed me home.

Today, I removed the carb, cleaned all the jets again, checked the needle valve is cutting off fuel and it's all fine.

Removed the plugs, cleaned them and checked they spark which they do. It's a Weber carb- see attached picture.

But still it won't start! Checked plugs after trying to start it and they are wet with fuel so it's getting through to the cylinders.

It has electronic ignition so no points.

What could be wrong that it was running and then spluttered cut out and now won't start?

One other thing I noted: the fuel return from the carb to the fuel tank has been blocked off so there is no way for excess fuel to make it out of the carb.
Could it be flooding the carb due to this?

But that's how it was for years before when it was running fine so don't see how it can be that?


Any ideas?

Thanks
Peter

crazypierre said:

Hi,
................................
This car had sat for over a year and it started immediately, although with an erratic idle (kept dying unless foot on accelerator.)
...................................................

Click to expand...

Drained Fuel?
Crap in Tank?
Crap in fuel line from tank?
Old fuel pipes breaking down duel to Ethanol fuel?

Cleaned all 3 filters?
(one in tank, one in fuel pump, one in carb)
fuel tank cap blocked preventing air entering?

It would be worth removing your plug-leads and giving them a good checkover. The sleeving they're in looks dodgy and and with that insulating-tape and the non-standard insulation where there should be a grommet on the rocker-cover there is scope to make things better whatever the cause of the problem.

Hi,
I put fresh fuel in.
The AA man did a test and the pump pumps out fuel fine to the carb.
I cleaned the filter in the carb itself and it's fine.
I tested the needle valve and it shuts off to stop the fuel flow once the float chamber is full.
Thanks
PC

Is it sparking at the plugs ok?

crazypierre said:

............................
I cleaned the filter in the carb itself and it's fine.
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Click to expand...

3 filters.....
pumping fuel out on the key does not always mean everything is perfect the demands are increased when running...
a rubber pipe could be collapsing or other crap being pulled into the filters then dispersing when not under load for a while...

If nothing has changed from when it ran fine then something has deteriorated or changed..

Check your compression in both cylinders.