Idle Jets 1969 Fulvia 1.3 Rallye S

[Shelley]

Hi Everyone,

I would really appreciate your thoughts / advice on the following please:

We collected our Fulvia after a three year restoration just before Easter and all was well, or so we thought although it did smell very 'rich'. I should point out the engine has not been rebuilt and is at 76000 miles. Prior to restoration, the car had been left in a garage for almost 40 years.

We clocked up roughly 100 miles after collection, in addition to the almost 100 miles done by the garage to test drive before collection. Then suddenly the car was difficult to start, it was misfiring and running like a tractor. It cut out with me travelling at around 30 mph. The smell of petrol was almost unbearable and there was a lot of smoke (not oil) coming out of the exhaust. We took out the spark plugs and they were all equally, completely black. We did notice however that there was a particular problem with spark plug number 4 whereby if the lead was removed it made no difference and if held at a funny angle the car seemed to run more happily.

Our Fulvia was collected and taken back to the garage where they have diagnosed faulty Idle Jets. The carburetors had been ultra sonically cleaned and re-built during restoration. Does this sound a reasonable diagnosis and is there anything else that could be faulty in addition to the idle jets or instead of?

Many thanks, Shelley

[neil-yaj396]

Much better Fulvia experts on here than me but this doesn't sound like idle jets, surely that would only effect idling and very low speed running?

Sounds more like a stuck carburetor float. Does the Fulvia have a fuel return? If so that could be blocked.....

[lancialulu]

I do not think that diagnosis is correct either. Unless they did not tighten down the idle jets during the carb restoration (has been known). If that is the case then the carbs should be examined to see if main jets too are loose from poor attention to detail. A Fulvia will run on a wide range of idle jets from say 40 to 60 - the larger sizes are sometimes used today to compensate for the lighter fuel and to better match the transition from idle circuit to main. It is the 4 mix screws that determine the mix at slow running and they can accommodate the idle jet variation.

It is also a known fact oft forgotten that a spark plug will fire better if the lead is a small distance away (c5mm air gap).

Check the fuel filter.... was the tank restored or is there muck in it... Often the case when a car comes to life it gets any dirt in the tank to the carbs. If no filter then maybe the float needles are stuck.

[Jaydub]

Black/sooty spark plugs and a strong smell of fuel normally indicates a flooding/over rich carburetor. I would check that the needle valves are seating/not stuck open.  As Tim said, by creating a larger gap between plug and lead will force the coil to give a stronger spark and clear a fouled plug, hence the reaction on No.4 plug. Check float levels are correct and retest. It might be worth while putting a set of new plugs in if they are badly sooted up.

[Shelley]

Thank you for your comments, they are greatly appreciated and I have fed them back to the garage in question hoping to get a resolution.

Kind regards,

Shelley