Car Jerking

[SvMinor]

Took the car out tonight, and for about 400/500 yards the car was jerking (not a smooth ride)then the jerking stopped, I thought it was because she was cold,

After bout half hour driving I pulled over and kept the engine ticking over,I then turned round and headed home and it started jerking again,this time it was worse than before,I adjusted the air mix and it continued to jerk for about the same as before about 400 yards.

While I had the bonnet up I revved the car it was a bit rough and sort of spluttery,made me think there was something wrong with the fuel pump,but it was clicking away,I could see petrol in the filter but not very much,
and there is Black smoke coming out of the exhaust.

There was the odd jerk from the car on my was home also.

Would this be a timing issue,I had the dizzy drive out and then the ignition was too far advanced(this was sorted tho)

What causes the car to jerk?

Why is there Black Smoke from exhaust?

How much fuel should be in the filter with engine running?

[bmcecosse]

Black smoke indicates too rich a mixture - check the choke is going off properly.

[SvMinor]

Too rich? =Too much petrol?

What would cause the car to Jerk?

Could the Timing be slightly out?

[mike.perry]

The only filter should be the one inside the fuel pump which you cannot see. Any other filters have been added later and are not necessary.
When the engine is up to operating temp adjust the mixture nut under the carb until you get the smoothest tickover

[alainmoran]

The timing is most likely the original source of your rough running, the adjustment of the mixture is probably what caused the black smoke.

Set the timing first, then adjust the mixture, then go back to the timing (assuming you are doing it by ear*) and then back again to the mixture.

* - I do have a timing light, but my engine seems to prefer it when I set the timing by ear! I set the timing till the engine runs at its smoothest - no burbling or missing - the first time around this will probably be setting it to where it runs fastest, but as you get the mixture set right there will be a point where it runs more smoothly than the fastest point.

[bmcecosse]

I too have a 'timing' light - had it some 30 years, an 'unwanted present' - never used it yet! Best way to finalise timing is on the road - keep on advancing it till you hear some pinking when working hard in top gear, and then retard it slightly again! Worth checking if the vacuum advance is working as it should. 'Jerking' can be caused by many things - most likely is a bad connection in the ignition system - loose rivets/contacts on the coil can be a cause.

[SvMinor]

I fiddled with the air and fuel mix a bit tonight,and got rid of the black smoke,Ive still to take her out for a run to see if the jerking has stopped yet,

Also loosened the choke cable slightly

I loosened the dizzy clamp and turned the dizzy slightly towards the rear or the car and also turned the adjusting wheel fully to "R" I hope this works.

[bmcecosse]

Well - you may have retarded it far too much - but it's a starting point!

[SvMinor]

What does retarded mean?(speed up or slow down idle)

Shoukd I not have turned the wheel on the dizzy so much then?

[bmcecosse]

You may have now set the ignition timing such that it fires 'too late', ie it is 'retarded'. Nothing directly to do with idling speed! Although it will affect how the engine idles. You should set the AR (Advance Retard) wheel in the middle of the scale - and then gently swing the dizzy forward and back until you sense the engine is idling at it's smoothest. Then lock it up - and do a road test listening for pinking. If none -advance a wee bit more and repeat. If pinking - retard it slightly. You must NOT let it pink for any significant time.

[SvMinor]

Thanks,Ill try that tomorrow