RR Classic Dizzy/firing order problems

[YamR1V64motion]

i changed the dizzy cap and rotor arm on my classic today as it seemed to move a bit while running and caused a slight misfire and lost power and used more fuel, i however got the firing order wrong when i put the new cap on and have apparantly corrected it again now using the correct firing order of 1-8-4-3-6-5-7-2

how i understood the number of the cylinders was:

left bank:8 right bank:7
6 5
4 3
2 1



however it is still misfiring and running pretty badly, does anyone know the correct position of the number 1 lead on the dizzy, i think i got it right but i may have been wrong and need to cure the car of this problem asap.

[eliot]

Looking from the front of the engine, cylinder 1 is at the front, right, close to the dizzy. No.8 is left at the back near the clutch/master cylinder.

Where is No.1 ? - It can be anywhere!

Only sure-fire way to establish it is to remove right hand rocker cover - turn the engine round by hand, once the inlet valve opens then closes - wait for the next TDC on the damper - that is No.1 position. Put the dizzy in and align all the leads from there.
I then usally put a dot on the dizzy and engine showing the alignment for the future.

[Steve_D]

eliot said:

...Where is No.1 ? - It can be anywhere!....

It could be anywhere but you will find that the the vacuum module will limit where the dizzy can sit and from memory it has less than one lead positions worth of travel.
Do as Eliot says and find No.1 compression (which you can also do by removing the plug and sticking your finger in the hole. As it comes up on compression it will try and blow your pinky out) and stop at TDC.

Assuming you have not removed the dizzy the rotor arm will be pointing at the correct position for lead 1.
The more normal layout will have leads 4&8 sitting in a line across the front of the engine and lead 1 to the right of 8.

Steve

[GreenV8S]

YamR1V64motion said:

i understood the number of the cylinders was:

left bank:8 right bank:7
6 5
4 3
2 1



however it is still misfiring and running pretty badly

Since it's running, at least one of the leads must be connected correctly. Since you have got the cylinder numbering correct above (although I think your 'left' and 'right' are reversed - it's normally described as seen from the driving seat) and the correct firing order, it follows that all the others must be correct too. Double check that all the leads are connected to where you think they are, and check both ends are secure. It's not uncommon to get air trapped under the end which can lead to them popping off after a little while. If you're running with plug extenders, remove them all and see if that helps. If you still have trouble, run it with the bonnet up when it gets dark and see if you can see any stray sparks. If it isn't that then you have some other fault. If the cap was moving around with the engine running that might indicate that a bearing in the dizzy is shot, for example.

[YamR1V64motion]

got it all sorted, it needed new plugs and HT leads too as some of them were pretty knackered.