E55 Coil Pack vs HT Leads Question

[Aussie Nick]

I would have a go at it myself personally. It looks intimidating with that big plastic cover. I often feel that it is like opening Pandora's box and that there is no return. One is doomed to be lost for ever.
Provided you have all the correct leads it will be a case of taking off one at a time and replacing it with a new lead. It might pay you to take a few clear photographs before you start and or put sticky labels on the leads you are about to replace and the replacement ones as well.Take your time and observe one lead at a time and peel off each lead slowly noticing the order of each clip you have to undo and which coil pack it attaches to. Ensure that the connection to sparg plugs and coil packs is secure. Sometimes one is fooled into thinking there is a secure connection when in fact there is none. I think you will be fine . Anyway you have all of us to fall back on if you get into trouble.Good luck it will be a piece of cake . And dont forget the sense of satisfaction.
Aussie Nick.

 

[television]

H there

Sorry for my ignorance, but who are GSF?

And any advice on replacing the HT leads myself?

Thank you!

GSF are German Swedish and french

www.gsfcarparts.co.

 

[mlsports]

Thanks!

Thanks for the advice Aussie! I think I will give it a go myself! I was just worried that the access to the leads might be really bad, making it a pig of a job.

With regards to GSF, are these genuine parts that they supply - or are they their own brand?

Finally, HT leads. I could not find any on GSF. Are 3rd party leads ok, and do any companies make the leads specifically for this car? I noticed that each lead is a custom length, so I'm thinking that any 3rd party leads should also be manufactured to match those lengths, so the timing is 100% correct. Any advice on that???

Thank you!



P.S. How the hell does that plastic cover come off anyway?

 

[television]

Thanks for the advice Aussie! I think I will give it a go myself! I was just worried that the access to the leads might be really bad, making it a pig of a job.

With regards to GSF, are these genuine parts that they supply - or are they their own brand?

Finally, HT leads. I could not find any on GSF. Are 3rd party leads ok, and do any companies make the leads specifically for this car? I noticed that each lead is a custom length, so I'm thinking that any 3rd party leads should also be manufactured to match those lengths, so the timing is 100% correct. Any advice on that???

Thank you!



P.S. How the hell does that plastic cover come off anyway?

The length is not that important and will nor affect the timing.

There is no reason why you do not test the leads with an ohm meter, they should be all the same allowing for the length if they are resistive leads

You can ask GSF about the packs, iwould think that they are genuine, saying that the MB ones are not very good.

Try also Euro car parts

 

[mlsports]

Testing

Thanks Malcolm!

With regards to testing them using an OHM meter - how do I do this? What two points should the meter be connected to?

I'm assuming the engine is running and I remove the lead from the plug and attach one side of the meter to that end, but where do I put the other end of the meter?

Or can I test the strength of 'signal' by connecting the meter just to one end?

Thank you!

 

[Aussie Nick]

Mlsports. SHOCKING SHOCKING. Please do not touch the leads or the coil packs with engine running. I dont know how you test them.This is best left to Malcolm to respond

 

[Aussie Nick]

As Far as unclipping the plastic cover . you will have to feel around the cover to establish anchoring points. I noticed that Merc generally use the straight clips with a bait hook type system . you may have to jiggle gently at least two of the anchorage points by applying some pressure in an upward type movement . you should be able to feel if they give away with a bit of persistent pressure and a jiggle. If you can borrow a small makeup mirror from some sheila try peeping up to see how the anchorage points bind onto the motor.This will establish the motion to be used to free the clips. Do not apply unnecessary pressure or you risk breaking the clips. Generally with Mercs the clips are simple but require you to think backwards. It is simply stupid but a little confusing.

 

[mlsports]

lol

lol - SHOCKING? It could be indeed!

I'll wait for Malcolm on this. Surely the coil pack needs to be firing to be able to test the strength of the 'signal'? Not sure that can be done if the engine is off?

 

[television]

lol - SHOCKING? It could be indeed!

I'll wait for Malcolm on this. Surely the coil pack needs to be firing to be able to test the strength of the 'signal'? Not sure that can be done if the engine is off?

I should have said the leads can be tested as the coil packs cannot.

The reason is that you cannot measure one short circuit turn in say 15.000 turns of wire. What happens is as you know, that when you remove the voltage from the coil, the magnetic field around the coil collapses back into the coil and produces the energy to spark the plug.

With just one short turn, this induced voltages is apposed by this one short turn that is out of phase to the rest and this will reduce the output, the same short circuit turn, and the loading it has on the coil, makes it get hot, reducing the efficiency even more to the point where the voltage disappears.

This fault is far less apparent on a multi coil engine as the coil is only powered for each firing stroke, making the miss fire get worse after a very long drive.

When there is only 1 coil that would get so hot after 5 min running that the car would stop until it has cooled down again, and that was always the tell tail.

There is a good cheap high vlotage tester out there somewhere,but I cant think of the name. you put it in series with the plug lead and it tells you if its good or bad

I will post back

 

[mlsports]

Tester

Hi Malcolm

Any luck with that meter name?

 

[television]

Sorry I over sleep some days

http://stores.channeladvisor.com/tools-n-all/items/item.aspx?itemid=181659

There are many variants, pop into your local motor factor see what they have

 

[mlsports]

Tester

Hi Malcolm

Many thanks for that!

So, I'm assuming that with this tester you pull the HT lead off of the spark plug, and plug the tester into the end of the HT lead and the other end on to the spark plug, THEN turn on the engine and see how it is firing (whilst idling). Is that correct?

Do these testers give a meter-like reading, i.e. 7 out of 10? Or does it just indicate if there is a signal, or zero signal (no signal)?

There doesn't look to be any form of readout on the tester? Any advice on that MUCH appreciated!!!

 

[230K]

Hi

That thing will just flash every time the spark pug gets a spark sent to it. It will not test if the leads are leaking to earth. It will only show up a very very poor lead. Again my opinion only. Best test for leads is to let the car idle in absolute darkness and look for sparks from leads earthing.

I can remember putting buttons between leads and plugs to strengthen the spark.

230K

 

[television]

Hi

That thing will just flash every time the spark pug gets a spark sent to it. It will not test if the leads are leaking to earth. It will only show up a very very poor lead. Again my opinion only. Best test for leads is to let the car idle in absolute darkness and look for sparks from leads earthing.

I can remember putting buttons between leads and plugs to strengthen the spark.

230K

Not quite, it will show a faulty coil pack with low out put.

Re the leads, yes in the dark you can see everything thats going on, re the button, my little Imp husky would only run with a spark gap on 2 cylinders

 

[230K]

But you proposed that this was for testing leads.

230K

 

[television]

But you proposed that this was for testing leads.

230K

It will if they are partial open circuit, If the engine is missing on 1 or 2 its very easy to see the difference with these things