Firing order

[Brian S]

I was changing my Vacuum advance unit the other day and while propping the dizzy cap out of the way 2 leads popped off.

When I checked the Haynes manual for the firing order it did not match up with the way mine is done

Haynes say

1, 8, 4, 3, 6, 5, 7, 2

with the left hand bank (Front of engine to rear) 1, 3, 5, 7 and Right hand bank 2, 4, 6, 8

When I changed to the Haynes settings the engine popped and farted and stalled and stunk of fuel so proberably wrong.

I have put it back and guessed the two that popped off. The engine runs and idles but not nice a smooth like a V8 should and I want to check the order.

Its an M reg 3.9 EFI by the way.

The exhaust is blowing from the downpipe which is being sorted next week so I am waiting to see if that improves the power and refinement I need.

 

[groenendael]

Firing order is 18436572
Looking at the engine bay from the front (IE radiator) the left hand bank is numbered 2468 and therefore the right hand bank is 1357.
May sure that ignition lead no 5 and 7 are not touching.
Source is Land Rover .

 

[Brian S]

Firing order is 18436572
Looking at the engine bay from the front (IE radiator) the left hand bank is numbered 2468 and therefore the right hand bank is 1357.
May sure that ignition lead no 5 and 7 are not touching.
Source is Land Rover .

Cheers,

Similar to Haynes except the left and right bank which could have been taken from the driver seat perspective.

I will check again, cheers.

 

[Brian S]

Wow.... I love specialist forum......

I've searched and asked for ages and one simple tip seems to have made a big diference.

All my leads are in the correct order but leads 5 and 7 were touching.

I have sorted that out and the Landy seems much better, idles better and after a short run up the road goes better. even the exhaust leak does not sound as bad.

I'll pick my daughter up from the nursery in it later for a good test but it seems a big thanks are in order....

Cheers.

Just a quick question though, some of the other leads were touching do I need to get them routed so they all are seperate?

 

[classic kev]

Just a quick question though, some of the other leads were touching do I need to get them routed so they all are seperate?

Yes. A couple of leads will be crossed over by the dizzy cap but route the leads into the clips on the engine and keep them separate, it doesn't hurt to give them a clean and spray the ends with WD40. Check manual for correct routing.

 

[CharlesY]

There's a special HT lead spray I think you can still get that we used in the good old days when we were competitoning in our Minis. It was called Ignition Sealer or something like that. You spray this stuff on BEFORE you take the car out in the rain. It worked very well indeed, by applying a nice shiny waterproof coating on the HT leads and the Dissy cap.

Worth trying, and spacing HT leads well to keep them apart is a good idea.

CharlesY

 

[Brian S]

Great, its running much better just seperating 5 and 7 so I'll spend a bit of time on it at the weekend to tidy up the rest since the drivers side was quite a spagetti junction.

Cheers guys.

 

[CharlesY]

Great, its running much better just seperating 5 and 7 so I'll spend a bit of time on it at the weekend to tidy up the rest since the drivers side was quite a spagetti junction.

Cheers guys.

The Rolls Royce Merlin Aero engines were V-12s with two spark-plugs per cylinder - 24 plugs, 24 plug leads!

So your eight leads isn't really such a big problem.

But a V-8 definitely sounds better when all 8 are firing in order!

You should try to keep the leads apart, and spaced well away from the metal bits of the engine.

AIR is a good "dielectric" (insulator) and so is DRY paper, waxed paper, plastic, dry oil, and all sorts of stuff like that. Dont be scared to use lots of plastic plug lead spacers to keep the leads in good trim, or to feed the leads through a plastic tube with each lead coming out a hole on line with it's plug.

CharlesY