Rover 418SD Engine Running On

[Ikeulike]

My ever reliable 1995 Rover 418SD has after 20 years unblemished service developed the fault of running on once the ignition has been turned off. Never did this until recent water pump/cambelt change. Have seen previous running on question but this is a diesel so is the answer the same?

[GTiJohn]

There's not a lot about the XUD engine in the Rover Service Mechanical Fault Finding Manual but what's there does point to the injection pump being worn or out of adjustment.

Does anyone else have more experience with these engines?

It may be necessary to find a local garage with experience of either Rover or Peugeot diesels who can help you.

[itcaptainslow]

It does sound like a stop solenoid fault. I’ve limited experience of these engines, but did have a XUD engine in a 106 diesel which I changed the cambelt on-it would be worth checking the fuel pump is timed up correctly as it runs off the cambelt.

You can do this by removing the covers armed with various sized drill bits-the camshaft & fuel pump sprockets have holes in them which align with holes in the cylinder head/pump housing, and there is a hole in the engine block to pin the flywheel. Obviously all of these should align and pin up. The fuel pump is easy to mis time as the sprocket spins by hand very freely.

[Julesmat50]

How long does it run on for? If it's just a few seconds, then the engine is using the little bit of fuel left in the system after the stop solenoid, which suggests the pump timing is out, especially as it only started happening after the cam belt was changed. The other possibilty is the fuel stop solenoid not working correctly, but that should only be an on/off thing.

A 100% mechanical diesel engine like the XUD in the Rover, will only stop if the fuel is shut off. As there is no requirement (unlike modern diesels) for any electricity to operate the injectors as they work soley on the pump raising the pressure in the pipes to overcome the return spring in each injector, once started the engine will continue to run until all the fuel in the tank is exhausted. The solenoid is mounted on the fuel pump, above the 4 injector pipes. Once the electrical supply to the solenoid is cut by turning off the ignition, the solenoid shuts the fuel feed, theoretically stopping the engine. The injection of fuel happens right before TDC normally, but as a diesel engine doesn't require a spark to ignite the fuel, if the pump is not sequenced correctly (because the timing is out) it's possible for the pump to inject the remaining fuel in the pipes into the engine which will ignite, powering the pump to inject to the next cylinder and so on until the pipes are empty.

[Ikeulike]

First of all Thanks everyone for you helpful suggestions.

I think the fault is likely to be the solenoid as when switched off it would just keep runnong unless I stalled it.

Will get the solenoid sorted. Hopefully this is not a rare Rover part as struggled to get a fuel filter the other day.

Thanks again

[961tat]

Had this problem years ago and got the solenoid from Peugeot at the 3rd of the cost from rover

[richard moss]

First of all Thanks everyone for you helpful suggestions.

I think the fault is likely to be the solenoid as when switched off it would just keep runnong unless I stalled it.

I'd say the same - after owning several Citroen BXs (great cars)