Replacing coil

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abovetherim
Posts: 594
Joined: Wed Feb 16, 2011 8:49 pm
Location: Leicester

Replacing coil

Post by abovetherim »

Back in November I had a little splutter when I was driving in the rain.
Now when I got the car 5 years ago I noticed the coil had cracks in the plastic casing. It still worked but should have been replaced. At the time I was on a deadline and very tight budget so I just sealed up the cracks with RTV silicon sealant.
Then yesterday on the way to work I was happily driving down a dual carriageway on the outside lane when the engine cut out on me. At this point the dual turned into 4 lanes at a massive junction/roundabout and I was on the right hand lane (the least used for this junction). So hazards on, out of the car for safety and on the phone to the AA. They took a couple on mins to answer and then going thro all the faff was another 3 or 4 mins, so before hanging up I thought i'd try to start it one last time. Thankfully she sprang into life.

My theory is the engine heat dried out the coil enough for it to work again but I knew I needed a new one. So once I got to work I phoned tcbparts @ 1pm and got the new coil @ 10am this morning :clapping: A good job really as the car wouldn't start this morning.

Now onto the crux of my post.... I don't need any help, I just thought I would post up some pointers especially as recently I have noticed a few posts relating to non start and poor running in the wet that could be related to the coil.

First up is my old knackered coil This is a rev 1 with 7mm ht leads so the part number is specific to that.
Image
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Now on those pics you can see the crack on each side and the rusty delamination on the underside. This lets the coil get damp and stops it working.

Fitted the new coil and she fired straight up.

Now on to pointers

Be careful when releasing the electrical connectors. They all have a clip of some sort that you don't want to break.

Be gentle with the king lead as they can be damaged especially the L shaped end at the dizzy (I had to replace mine a couple of years ago as it had snapped inside the insulation at the corner of the L)

When I went to remove the coil from the bracket I found the machine screws wouldn't budge, not 1 of the 4. I had to drill the heads off them. I found a 6mm spot weld bit was perfect for this.
So You may need 4 off M4 x 15mm pan head machine screws

On refitting I ran a tap through the threads on the bracket and added a little copperslip. After fitting the coil I covered the heads and ends of the screws with Vasoline.

Whilst the bracket is off the firewall also remove the igniter and clean up the mounting points on the bracket for the coil, ignitor and bolts. I used some coarse sandpaper for this.

Access to the coil is improved by releasing the fuse box from its mounting points. Beware of the bolt in the corner by coolant bottle top. This can seize in its bracket and snap off (no need to guess how I know this)

Basically this 10 minute job could turn into a couple of hours

HTH
cosmos
Posts: 594
Joined: Fri Mar 10, 2006 9:58 pm
Location: Warwickshire

Coil

Post by cosmos »

Jan thanks for an informative read with pics, appreciate all the effort you went to.
Rob.
Willenium
Posts: 348
Joined: Tue Jul 05, 2011 10:36 pm
Location: Herts

Re: Replacing coil

Post by Willenium »

Good useful post :thumleft:

I did mine a couple of months ago and can confirm all the above are pretty much the steps I took also. Only differences are I used Red Rubber Grease on the threads and to fill the bolt recesses instead of Copper Grease and Vaseline and after rubbing down the contact points on the bracket I finished them with Autosol.
Kiddo
Posts: 95
Joined: Mon Apr 13, 2015 10:12 am
Location: Herne Bay, Kent

Re: Replacing coil

Post by Kiddo »

Nice one abovetherim, this was the one job I didn't get around to doing last year so your info will come in handy when the time (and weather) comes! :thumleft:
gnzyza
Posts: 1300
Joined: Wed Jun 27, 2007 11:39 am
Location: Gloucester

Re: Replacing coil

Post by gnzyza »

Thanks for the info...rather than using RTV , plasti welding would be a more permanent solution. You can use a old soldering iron and cable ties if stuck. (ghetto), heat up a V groove into the crack then back fill plastics and spread. If some areas are prone to pulling apart you can bury staples into the plastic too.
benjo
Posts: 284
Joined: Tue Jan 06, 2009 11:40 pm
Location: Under your bed

Re: Replacing coil

Post by benjo »

I did mine last year bought new bracket from toyota for £15
Came with new screw for the coil not worth messing about drilling screws for
That much money,plus I believe the bracket works as an earth and mine
Was bit rusty so better contact
mr2magic
Posts: 643
Joined: Fri Apr 09, 2010 9:33 am
Location: Hannover, Germany

Re: Replacing coil

Post by mr2magic »

^1 this. The bracket serves as an earth to the chassis so do not use any dielectric grease or insulator (like rubber compound) to 'protect' the threads from galling.
abovetherim
Posts: 594
Joined: Wed Feb 16, 2011 8:49 pm
Location: Leicester

Re: Replacing coil

Post by abovetherim »

That is correct tho I believe it is only the ignitor that requires the ground but I could be wrong. But this is why i cleaned off the bracket.
Also notice I used copper slip on the threads and only covered the heads and the exposed thread after fitting in vasoline to stop them corroding.
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