Frog eye 948cc cuts out

[bazjude2998]

Just acquired a Frog Eye,after 20 miles or so engine cuts out (fuel starvation.Or ignition?)
Leave for a while and springs back to life.All suggestions greatfully received.

[Grumbly]

Try a differnet coil, failing coils often cut out when they get hot.

[phumy]

Yup new coil required

[E-bmw]

^^^ Most likely problem, had it many years ago in an early 320i, RAC man diagnosed it on the spot, coil gets hot, insulation breaking down, 10 mins later, all was good.

New coil fitted, never an issue after that.

[julianm]

One of these is meant to be extra sparky!
https://www.ebay.co.uk/itm/171681101274?mkevt=1&am...

[GreenV8S]

Put a passive strobe in line with one of the HT leads and see if you still have a spark.

A heat related coil failure would fit the symptoms, but is not the only possible explanation. Best to diagnose it rather than just throw parts at it.

[SystemOfAFrown]

Coil would certainly be a prime suspect, but if it has the original contact breaker system then it could also be the condenser. A lot of the condensers made in the last 10 years or so are absolute crap.

[Ambleton]

First port of call is to check the really easy stuff!

Check the fuel cap.
Heard it before where the venting part has failed and causes a vacuum in the tank as the fuel is being pumped out. There's only so much the pump can overcome before you get starvation.

Fuel lines. Any that are degraded or pinched/damaged? Or that run near the exhaust causing a potential vapour lock.

Coil - as others have mentioned often degrade and are inexpensive. Get a good quality dry coil. They're cheap as chips.

[Peter Burgess]

The rotor arm becoming conductive when hot and shorting out until it cools down after 20 minutes or so is very very common and annoying trying to find the problem. Solved by fitting a modern red rotor arm.