BACKFIRING

 

After driving some months, you may have experienced that your engine will not stop when you turn the ignition off. This is often due to some deposits of carbon in the combustion chamber and on the spark plugs. When it is really bad, you will ask your mechanic to take off the cylinder head and clean the engine inside.

However there is an easier method you can use and do it yourself.
You can pour clean water into the carburettor when the engine is warm after around 10 km driving. When the water enters the combustion chamber, it will evaporate and blow off the deposits.

You take off the air cleaner and put a hand on the throttle and keep the engine running at about 2000 revolutions and then pour water into the carburettor until the engine nearly stops. When the engine gains speed again, you pour in more water. 30 to 40 centilitre should be sufficient.

It is an old and well proven method and often it will cure the problem. If not, you should inspect your spark plugs.

The correct spark plug for a Morris Minor is Champion N5, superseded by N9Y and later N9YC and today RN9YC.
Many other brands have a spark plug that should supersede Champion, but often it fails.

When I am at a rally here, I always have a set of Champion spark plugs with me. Often a club mate will have trouble with starting the engine, and when I can see a set of new spark plugs of some other brand in the engine, I will ask him to fit my Champion spark plugs. Nearly every time it will cure his problem instantly.

At our Rally 2009 I demonstrated how to pour water into the engine and you can see the video on YouTube.

Best regards
Anton

June 2009