What is the firing order on distributor cap for 1956 Morris minor?

Answer 1

The 1956 Morris Minor is fitted with an A Series 4 cylinder engine which until during 1956 was an 803CC overhead valve engine ( later changed to become a 948cc overhead valve engine. The Firing order for both these engines is 1,3,4,2 with number 1 cylinder being closest to the radiator at the front of the car. If the timing chain is properly fitted then looking at the distributor, number one should be at around the 4 o'clock position.

To establish the correct timing, one must establish TDC which means Top Dead Centre of the number 1 cylinder to line everything up. The easiest way is to remove the rocker cover, and turn the engine over from the fan blade / water pump pulley or using the starter handle. Remove the spark plug from 1 cylinder, and gently insert a screwdriver and turn the engine until the screwdriver is pushed out of the spark plug hole at the maximum piston position. Do this carefully, because it is possible to jam the screwdriver and damage the cylinder walls or piston itself. The correct position when the cylinder 1 piston is at TDC should be with both valves in the closed position which can be identified by the rockers at cylinder 1 being perfectly horizontal.

Now climb under the front of the car and shine a torch upwards at the crankshaft pulley wheel on the front of the engine. There should be a dot stamped on the pulley wheel which should be lined up with the longest spike attached to the timing chain cover. Line the long spike up with the dot. That should be precisely TDC.

Now, ensuring the distributor cap is off, look to see where the rotor arm is pointing. The closest high tension lead to the pointing position of the rotor arm is Number 1. Then fit back the distributor cap and fit the high tension leads so that they are 1,3,4,2 going anti clockwise.

Strictly speaking, the Trumpet ( the vacuum advance unit ) attached to the distributor that has a pipe sticking out of the top, should be pointing almost perfectly towards number 3 cylinder. You can now start the engine and it should run reasonably well. To fine tune the distributor, simply slacken off the distributor locking bolt a touch, so you can with a bit of force move the distributor backwards or forwards. Plug the pipe that comes out of the vacuum advance unit and rev the engine up a little and adjust the distributor forwards towards cylinder 1 until the engine begins to run slightly unevenly, then turn back a little. That should be the perfect timing position. You may experience a little bottom end rumble if the timing is too far advanced. Simply retard a little to smoothen out the revs.