Poor quality dizzy caps/screws too long

[carrierdave]

I recently received a shock when adjusting the timing on my car. I removed the cap and leads to see if I could find any obvious reasons for the jolt.
Looking closer at the top of the cap I could see a small protrusion on the cap, just behind where the leads entered.
What I discovered was that the screws inside the cap, which screws through and holds the ignition lead in place, had gone through the lead and then on through the cap! It hadn't cracked the cap, just pushed its way through the plastic.

So just a word of warning, either reduce the length of the screws, or be very careful when fitting, to ensure you don't screw them in too far.

Dave

[Chancer]

A bad workman always blames his tools, or in this case the materials

Are they not grub screws if my memory serves me correctly?

If so then if they were not that length you could screw them out of their threads and into the lead which could then detach while running.

I suspect they were always that length and you are probably not the first to do what you have done but you are the first I have ever heard of doing so!

[john.p.clegg]

Or,new chinese crap dizzy covers are on the market..

John

[carrierdave]

They are a little grub screw with a sharp point that cuts into the HT lead. The thing is there doesn't appear to be anything the other side of the thread to stop it from going through the cap wall!
The material used in the new cap seems to be much softer than the old style caps so it is quite easy to over tighten the screws and push it through the top of the cap.

The cap came from a Lotus parts supplier so I would have expected something more robust.
I've gone back to using the old cap for now, until I can have a look at PM's to see what they have on offer.

Dave

[Elanintheforest]

Dave, get a new set of bits from the Distributor Doctor. He only sells top quality caps, rotor arms, condensers, points and coils, many of which he has had remade in the UK to original or better specification.

http://www.distributordoctor.com/

Mark

[carrierdave]

Thanks Mark. Certainly from the pictures on the web site, the caps look more like the original material than the one I was supplied with recently.

I'll give them a call

Dave

[Orsom Weels]

A bad workman always blames his tools, or in this case the materials

Are they not grub screws if my memory serves me correctly?

If so then if they were not that length you could screw them out of their threads and into the lead which could then detach while running.

I suspect they were always that length and you are probably not the first to do what you have done but you are the first I have ever heard of doing so!

That's rather harsh !

No, they are not, or should not be grub screws, they should have a cheese head which bottoms out before the point can push it's way through the cap. This enables the screw to be tightened against something solid so as not to vibrate undone or damage the cap.

This is what it should look like.

[carrierdave]

That's interesting. The ones in the particular cap I have are straight, with no head/shoulder as your photo.
Having this head would certainly eliminate any chance of the screw being driven in too far - can I ask where you got the cap from?

Dave

[Orsom Weels]

can I ask where you got the cap from?
Dave

That particular screw is from an Intermotor cap & came from a local general motor factor that I deal with in connection with my business, but should be readily available elsewhere. Original Lucas caps had the same arrangement, so I would guess that a Lucas branded item would/should have the same type screw arrangement now, although I will say the motor factor concerned had been a Lucas agent & sold their wares for many years, but have switched to Intermotor as they were not happy with the quality of some of the new Lucas components, they were getting too many 'returned as faulty' issues.
The plastic/Bakelite or whatever they use now is very thin above the lead exit & without the shoulder provided by the screw head, I would imagine it would be very difficult to judge how far is far enough, & very easy to go too far, as it sounds like you've found.

Regards, Tim

[gjz30075]

How about using the old screws in the new cap?