Breaking down after 4-6 miles ?

[brian]

Hi,my 1961 moggy starts reasonable well,but after 4-6 miles cuts out,after a few minutes it starts first time,I have replaced dizzy cap and leads and plugs and coil,cleaned carb,moved fuel pipe away from heat and added a fuel filter,any clues.cheers,Brian

[mogbob]

Brian
Does it instantly " cut out " or " spluter " to a gentle halt ?
If it is instant ,I'd spend a pound or two on a new condenser.If only to eliminate it.

But before purchasing.. are you happy with the short wire ( white with black tracer ) from the coil to the distributer.Sound clean, firm connections and no chaffing on the wire itself.
Ditto is the low tension lead, on the side of the distributer( sometimes referred to as the pigtail lead ) in good shape or just hanging on with a few strands of wire.
It sounds like an electrical fault, with heat and subsequent cooling, playing a part.

Bob

[newagetraveller]

Try taking the petrol filler cap off. You may have an airlock.

[MarkyB]

Does the petrol pump give a tick or two when you first turn on the ignition?
If not replace the points or the pump.

[bmcecosse]

It's 'never' the coil...... Could be the condenser heating up - change it!

[brian]

Thanks gents ,that gives me a few things to work on,I will let you know the results,cheers,Brian

[bmcecosse]

It may be the restricted air flow through the grille...........

[beero]

If you have added a fuel filter it could be that restricting the flow of petrol. Try removing/renewing it.

[brian]

Hi,I have only just fitted the fuel filter at the same time as moving it away from the engine heat,and I also fitted a new air filter and made sure it was in a good airflow position.cheers,Brian

[bmcecosse]

The fuel filter is NOT a good idea. The pump already has a filter and in any case the SU carb tolerates dirty very well. The filter can just hamper the fuel flow leading to a possible 'fit of the vapours' in hot weather.