Technical X1/9 stalls without warning

[jimrat]

Hi

My X19 will idle happily, but after 3-5 minutes driving around town, it stalls without warning and will not restart. I have to wait 5 minutes, then it will start again, and the cycle is repeated. It’s a 1500 Euro X19, standard except for electronic ignition and electric fuel pump. It’s just coming out of a 3 year nut-and-bolt resto, so absolutely everything has been apart.

It feels electrical because it stops so suddenly, but after its stalled, the dash battery light is on, I can hear the electric fuel pump whirring and there is still +12V to the coil. The ignition switch and battery are new, and the alternator is kicking out 14.4V.

All the ignition parts are new, including the coil. I fitted a spark indicator on one of the plugs and the spark is bright and even. Static timing is set to 5 degree BTDC and the centrifugal advance checks out. The car pulls nicely.

I’ve checked the fuel tank pick up for dirt, and the fuel tank is not under vacuum. The fuel filter is full of fuel. The carb has been cleaned and a refurb kit fitted, and the float level is set correctly. The spark plugs are not fouled. The cooling system is in good shape, and the temp sits at 90 with the fan cutting in and out OK

One thing I have noticed: if I remove the oil filler cap when the engine is running, I can see oil flying around inside the rocker cover, and oil will spit out of the cap. Is this normal – I’ve never had this on any other car?

This has been going on for weeks, and I’ve checked and rechecked fuel, spark and air several times- I’m completely stumped by this. I can't believe it’s the fuel vaporisation issue, as it’s winter here in the UK, and I have the electric fuel pump fitted.

Any ideas?
Thanks
Jim

 

[sledgehammer]

I've had a similar problem to this in the past. Turned out to be a leak on the inlet manifold to engine gasket.
It would make sense in your case, runs fine when cold, as engine heats up any gaps get bigger and the problem presents itself.
Could also be a leak topside of manifold to carb.
Worth a look IMO

 

[jimrat]

Thanks for your reply Sledgehammer.

The carb is definitely sealed tight to the inlet manifold. I did have to tighten the inlet manifold bolts the other day as they were a bit loose.

That's got me thinking though - I might do a cigar smoke test on the inlet manifold to see if there are any leaks anywhere.

 

[porta]

The most common cause is fuel evaporation wehn warm/hot. Make sure that fan is working properly

 

[jimrat]

The most common cause is fuel evaporation wehn warm/hot. Make sure that fan is working properly

Hi, The carb fan has been sacrificed for an electric fuel pump and electronic ignition, which lots of posts seemed to suggest would be more effective at preventing hot start issues.

 

[porta]

Hi, The carb fan has been sacrificed for an electric fuel pump and electronic ignition, which lots of posts seemed to suggest would be more effective at preventing hot start issues.

This is true, I did contemplate going that route on our original Exxie but went for a carb spacer and a better fan. I also slightly rerouted the fuel pipes and we never had an issue after that

 

[sledgehammer]

Hi, The carb fan has been sacrificed for an electric fuel pump and electronic ignition, which lots of posts seemed to suggest would be more effective at preventing hot start issues.

I don't think this would cause stalling. I had a 79 x19 back in the 90's and it was awful at restarting after stopping. It used to overheat all the time. Never stalled though.
I'm wondering if the inlet manifold bolts were loose and its leaked can it be resealed just by tightening the bolts?