V12 dist cap/rotor

The 8mm wires have better insulation and are slightly more flexible although thicker. The 7mm wires will go in the original plastic shrouds although Magnecor do not recommend this as it is the primary cause of failure on this vehicle.

The 8mm wires increase voltage capacity from 35k to 55kV and have a much higher thermal resistance.

7mm wires are black for the OEM look, 8mm wires are blue.

8.5mm wires are OTT for a stock engine and 10mm will not fit at all.

Price difference between the 7mm and 8mm is minimal so the 8mm is the best value unless you want black.

ALL LEAD SETS I SELL COME WITH BRAND NEW OEM IGNITION LEAD SENSORS, NOT EXCHANGE, USED OR PATTERN ONES.

8Tech.

8Tech,

is there a way to find out the production year of the plug wires? is it printed on them somewhere (as with most parts)?

Cheers and thanks for the infos!

Zitat von martinw;57636

Gerry,
Which are the ignition lead sensors you mention ? The pulse generator ones ?
Also, do your Magnecor sets come with the "marten repellers" ?
(see new thread)

Martin, I bought a set of the Magnicor (8mm blue) from Gerry, they're not fitted with the Marten repellers but I'm not overly worried about that, the leads are great.

Zitat von martinw;57636

Gerry,
Which are the ignition lead sensors you mention ? The pulse generator ones ?
Also, do your Magnecor sets come with the "marten repellers" ?
(see new thread)

Yes, the sensors I refer to are the pulse generators on leads 6 and 12.

Yes, I can do the 7mm sets with marten repellers if you so desire, but not required here in the UK.

8Tech.

Zitat von fuzzifikation;57629

8Tech,

is there a way to find out the production year of the plug wires? is it printed on them somewhere (as with most parts)?

Cheers and thanks for the infos!

Not sure if you are enquiring about the OEM or Magnecor leads but the answer to your question to either is NO.

8Tech,

Zitat von martinw;57781

Jason,
Good to hear that you're happy with them.
As yours are 8mm, I guess they don't fit inside the the original trunking (running down the side of the heads) ?
If thats the case, how did you run them and keep them in place ? Some sort of cable ties ?

BTW, I was joking with Gerry about the marten repellers :). I think I can well do without them, even if it is a loss of originality.

Magnecor state that the primary cause of failure of leads on the V12 is the plastic trunking and IMHO cable ties should only be used loosely, not tightly clamping the cables together.

I recommend proper plastic or alloy HT lead seperators, available from most good motorsport suppliers. (Demon Tweeks etc)

http://www.demon-tweeks.co.uk/…MSPORT&pcode=MOC20-252BLK

8Tech.

I replaced the caps, rotors (eurocarparts £120) and put on the 8mm magnecors Gerry sent me. My old caps were stamped "90" which was the build year of my car so they were 18 year old originals (although the new caps are stamped "80"!) and were in a terrible state, the rotors particularly, it was amazing the thing would run.

I've convinced myself that the car has more power now, it seems to like revving higher, although it could just be my brain trying to justify the expense.... I'll keep an eye on the fuel consumption that was always much worse than I was expecting (gentle driving was getting 14 - 16 mpg, 18 - 19 on a motorway run) and let you know what happens.

Mystery solved

So Gentleman (ladies?)

I have been having problem lately that has been a bit problematic to pinpoint.
Car starts perfectly every time but after ~10km and stopping to crossing I was feeling lack of power. There was also rough idling and hesitation in acceleration.
The warmer it got the worse the problem. No lights in dash flashing etc.

In desperation today I decided to change the original (from 1991) distributor caps and rotors. This is what I found.

Here's the question...what was the problem you think?

I take it that it fixed the problem since you ask?

I can only guess, but there was probably a small crack in one of the old ones, when cold it was sealed, but when it heated up the crack opened up and air came into the cap.

I'm not sure exactly why this causes the ignition to fail, but this used to be a common issue 20+ years ago.

in the third photo, the middle carbon contact-pin seems broken to me. The middle pin should look like pic #2 - it should stick out and be spring supportet. The more I look at your thrid picture, the more I am convinced that that thing is a goner! A common failure - from what I read in the German part of the forum.

PS: mine looked like your #2 - fine, that is. Never the less, I decided to exchange caps and rotors (which I did last weekend) and combine them with my new magnecor leads (thanks to 8Tech). I figured that after 100 thousand kilometers (60k miles) it couldn't hurt to update these parts as they are, indeed, a common reason for trouble. I'm starting her up tomorrow but don't expect any significant change in behaviour.

Yep, it was gone...no idea what happened there, never seen that before. There was excess black stuff inside the cover and burnt smell from the arching. The centre electrode is approx 5mm below the surface and the rotor is heavily corroded so this has been there for some time.

And remember it was still providing spark, just if I tried to use full power it was having a problem...amazing.

Just last summer I made a 2000km holiday trip (to Northern Finland and Sweden) most likely with this ongoing all the time.

Being an old git, I can explain, (but not excuse), the reason you all seem to be driving around on totally worn out caps and rotors.

In the old days, when cars had contact breaker points, these "points" would be checked and regapped normally every 6000m or so, and replaced every 12000m and in doing so, you or the dealer would remove the cap and rotor to do it. It was on the service check sheet schedule. You would then see any cracks or tracks and replace as necessary. Refitting and setting the points also then involved resetting the ignition timing.

With the advent of electronic ignitions, these checks and adjustments were not required and the load on the caps and rotors was vastly reduced, to the extent that they were supposed to be checked only at 24000m+. This made everyone lazy and if it was running ok, then they got overlooked. They seldom needed any attention to be honest at 24000m so the next inspection was 48000m, by which time most were out of the dealer service network.

SO

They were NEVER actually checked until there was a running problem and almost no dealers ever needed to look at them on service.

8Tech.

I guess 8Tech is right.

I changed mine at about 130.000km, with the plugs, plug leads and the coils.
They still looked ok, a little burned but not to bad, and I guess they where the original ones from 1990.

I did get a smoother idle, and better consumption after changing these parts.
I had trouble getting below 20l/100km before on mixed driving, and I could smell unburned fuel in the exhaust.
After I changed them I have no problem running 15l/100km if I'm careful, but my norm is about 16l.
At long hauls I can get her down to 11-12l/100km now.

Zitat von Algernon;59083

So Gentleman (ladies?)

I have been having problem lately that has been a bit problematic to pinpoint.
Car starts perfectly every time but after ~10km and stopping to crossing I was feeling lack of power. There was also rough idling and hesitation in acceleration.
The warmer it got the worse the problem. No lights in dash flashing etc.

In desperation today I decided to change the original (from 1991) distributor caps and rotors. This is what I found.

Here's the question...what was the problem you think?

Alles anzeigen

I'll add the following just for future reference and completeness, in case it may help someone.

Lately, I had the same problem described above, with the engine seemingly OK until after a few miles of driving, when it would then become hestitant and less responsive. Yesterday, I changed both distributor caps and rotors, which has brought the car back to normal (power restored and smoother idling. The interesting thing is that my old caps looked exactly like those in the pictures above (OK, not quite as bad on the worn one, but similar).

I think the cause of my problem was having sprayed one cap some time ago with WD-40 oil, which seems to have gummed-up the centre carbon-contact on the cap, causing it to wear severely (due to restricted movement). Of the two pictures posted by algernon, the one with the damaged centre electrode, seems to be a bit oily on the inside, so I'd bet it was caused by the oil drying up and causing the electrode to stick, as happened to me.

So the moral of the story here is perhaps never to spray WD-40 or similar on the inside of the caps.

Hi Arnie,
you could well be right there. It's a very common misconception that WD-40 is a lubricant - it isn't, it's a water repellent agent (the names comes from Water Displacement 40th formulant) and although it appears to have some lubricating properties, these are of short duration and in a short space of time the opposite effect is apparent. It contains only about 15% mineral oil content, the rest of it is solvent and CO2 gas as propellent.
In short, don't use WD-40 in place of proper lubricants.

Cheers
Jason

Zitat von arnie;60091

I'll add the following just for future reference and completeness, in case it may help someone.

Lately, I had the same problem described above, with the engine seemingly OK until after a few miles of driving, when it would then become hestitant and less responsive. Yesterday, I changed both distributor caps and rotors, which has brought the car back to normal (power restored and smoother idling. The interesting thing is that my old caps looked exactly like those in the pictures above (OK, not quite as bad on the worn one, but similar).

I think the cause of my problem was having sprayed one cap some time ago with WD-40 oil, which seems to have gummed-up the centre carbon-contact on the cap, causing it to wear severely (due to restricted movement). Of the two pictures posted by algernon, the one with the damaged centre electrode, seems to be a bit oily on the inside, so I'd bet it was caused by the oil drying up and causing the electrode to stick, as happened to me.

So the moral of the story here is perhaps never to spray WD-40 or similar on the inside of the caps.

Alles anzeigen

Jason,

Yes, what you say is correct. One of WD-40's many advertised uses is for repelling damp on ignition systems. But the residue oil-film soon dries and goes tacky, particularly in a hot environment. Added to which, the mineral-oil probably carbonises further in the presence of high-voltage, making things worse. So, it may be good to use these sprays on the external components, but I think using it on the inside of the distributor cap was a mistake.

I think that with the springy, centre carbon-electrode gummed up, a period of rest would allow the spring to push it back into contact with the rotor, but whilst driving the car, any play in the rotor shaftwould then push the contact away again, making the engine lose power, and increase local arcing. This is why at the beginning of a drive, the car would seem fine, and then gradually worsen.

Arnold.