Idiot's Guide to dizzy/leads/rotor arm/spark plugs replacement?

I am a willing but very inexperienced mechanic and would be grateful for a very simple guide to replacing the above items, before I take this job on in the morning (all part of the learning process). My '94 V8 Classic has been struggling to start for a while and I have foolishly let it get to the point where it now wont start at all, possibly made worse by the recent damp weather. It cranks OK and fuel is definitely flowing. The RAC came out this week and spent over an hour checking everything including cleaning the plugs, distributor cap, checking for a spark etc. but diagnosed an inadequate spark and recommended I replace the plugs, leads, dizzy cap and rotor arm, all parts I have picked up today. This looks fairly straight forward but I just want to be 100% sure I do everything in the right order and that there are no 'peculiarities' about the Rangie that I need to be aware of when taking this on. A simple step-by-step guide would be really appreciated and if it does the trick and gets the old girl going, it will mean I can get her to her MOT appointment next week!

Thank you in advance

It's an engine. O.K. it's a big engine with a lot of plugs and wires but it's only an engine.

First of all don't listen to anything that Dr. Evil says.

Then replace one plug and it's lead and fit the other end into the correct place in the new dizzy cap. Then do the next plug and so on.

Replace the rotor and you should be away.

People usually run into trouble by disconnecting all the leads at one go then, if it doesn't start, questioning if they're back in the correct order.

number leads 1,3,5,7 on passenger side from front and leads 2,4,6,8 on drivers side from front ,remove leads on plug end and leave connected to cap ,remove cap and place cap with leads spread out on a bench etc place new cap in front of it ensuring both caps have locating lug in the same position fit new leads by length as old cap and number leads as you go,you can then change plugs ,gap new one 30 thou , pull off old rotor arm and fit new cap and leads can then be refitted

Thanks guys, much appreciated. I have a note of the firing order, just in case, but your method sounds much easier. Re: the rotor arm, am I right in thinking I need to mark exactly where it was positioned and install the new one in the exact same position?

rotor arm has a lug will only fit on one way , it ensures you put the right length leads in the right place

Caution removing the rotor Rm, if it is stuck or stiff to remove, it could lift the rotor shaft and knock the bob weights off there pegs meaning you'll have to remove the dizzy to replace them again, not hard just a pain in the arse to get dizzy back in again and retimed is all.

One problem with the old V8 system causing weak or no spark is breakdown of the rotor arm insulation. There is an easy way to check this.....remove the dizzy cap and unplug the main HT lead from the centre of it. Holding the end of the lead with a WELL INSULATED pair of pliers about 6-8mm away from the brass wiper on the rotor arm, get someone to give the engine a quick spin over with the starter. There should be no spark tracking across if the rotor arm is good-if there is a spark, the rotor arm is knackered and causing the vast amount of HT voltage to track to earth instead of going to the spark plug.
Only buy genuine LR rotor arms..the vast majority of new aftermarket one's will fail, even straight out of the box.
Instead of just attacking starting problems like a bull at a gate and changing everything, the system should be checked methodically-one step at a time, working from the coil to the plugs.
The rotor arm check I have given will be a vital part of this.
Good luck:

Thank you all for the advice, it is much appreciated. I will let you know how I get on

I changed all the electrics on the Classic Vogue I had. After a week it would not start or would run rough. After a lot of ****in around, I replaced the new rotor arm with the old one. Ran as sweet as a nut after that. Apparently they don't like aftermarket rotor arms.

One recomended way of removing the old rotor arm is to cover it with a cloth & then tap it with a small hammer, thereby breaking the plastic so the 'arm will fall off the shaft. On the subject of spark-plugs I've only ever used Champions & never had a problem (I don't run LPG) although others will recomend various other brands I can only speak as I find. Properly maintained RV8's are not known for starting problems, my 3.5efi's have always fired up within a few turns (usually on the first) even in damp weather & after infrequent use.

All sorted. Got the new parts fitted yesterday and then found the battery was badly drained from efforts earlier in the week to get her going. Various issues made a jump start difficult, including the wife's BMW having a daft battery arrangement, so trickle charged it over night and..... she fired up perfectly and is driving brilliantly now! What a difference this has made. Massive lesson learnt and thanks to you all for your help and guidance. Apart from a few bruised knuckles, it was all very easy.

norseman said:

I've only ever used Champions & never had a problem (I don't run LPG) although others will recomend various other brands

Click to expand...

I have had duff Champion plugs several times over the years - never had a problem with NGK!

StuckAgainSteve said:

I have had duff Champion plugs several times over the years - never had a problem with NGK!

Click to expand...

Well there you go - checking the service history of my previous 3.5efi (also non LPG) I was suprised to see how many sets of plugs it had needed over a period of about three years. A check on the part nos. revealed them all to be NGK! The first service in my ownership included Champion products & the car still started & ran well when I sold it several thousand miles later. I'm retired now & my current 3.5efi regulary stands (on an open car park) for a week at a time & always starts first time - summer or winter.