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MG Midget and Sprite Technical - HT lead problems

My HT leads need replacing and noticing for sets they mention about needing top entry dizzy caps. now the clearance between the cap and steering colum would mean that isnt possible.

Has anyone had this problem and is there a solution. its a 45d dizzy by the way not 25d ( i know wrong for my car).
D Sartain

D. A little more information, please. First, is your side entry cap made to use a push on lead or, like the early caps, does it require that you insert the lead into a hole, then tighten a set screw from the inside of the cap?

With the early style side entry caps, the ones we used back in the 1960s, we made up wire sets from copper wire and spark plug terminal caps. Volvo caps were considered to be of better quality than the BMC caps then available. You can still find the parts to custom build a set of HT leads using copper cored wire and installing the spark plug terminal caps yourself. You can, also--I am told by Brit friends, take the standard leads, cut the push on end off, and install them into the side entry caps.

If the modern caps have the push on style leads, I do not see where there is any problem. A large number of people make lead sets that would work. All a prepared/pre-made lead set is are the required number of leads to the required length. Thus, you can measure the length of your current leads and note what lengths are required. At that point, if there are no leads available for the Sprite/midget, look for something close like the MGB. As long as the leads in the prepared kit are as long as the current ones, or just a little longer, any HT lead kit will work, as long as the spark plug terminal ends are made for the same size of spark plug your automobile uses.

There is nothing magic about the use of a prepared set of HT leads. You can, fairly easily, make your own, or use a set for a different engine (within reason--none too short or excessively long).

As to distributors, your Lucas 45D4 should use the same lead set as the 25D4 did. The differences between the distributor caps was not in the size of the lead needed and any lead should interchange between the two distributors. In almost all cases, a push on lead is a push on lead, regardless of brand and style of dizzy cap. The same applies to the holes used in the side entry caps having a set screw in the bottom to hold the leads in place.

Les
Les Bengtson

sorry yes its the push on type didnt think many had screw in and thought that it was only the coil that was a screw in type. Also i was thinking that but for it actually saying it means something surley.

thanks for the input
D Sartain

The early side fit caps used a pointed screw that came up from inside the cap and, as it was turned down, broke through the insulation to make contact with the copper wire inside the sheath. This was the system on my 61 Sprite and my 53 A-H 100. Little need for the side entry cap on our side of the pond, hence I have not seen one in use for something over 30 years now. With the push on style cap, all you need to worry about is getting leads of the proper length. Should not be a problem.

Les
Les Bengtson

I have an Aldon dizzy which is basically a 45D Lucas. It has a side entry cap with push on leads. I use a set of leads from an mgb roadster (1976-1981). My leads happen to be Lumenitition ones (for which the product code is HV507) but I guess any leads for that MGB would fit. Lunitition ones are expensive but the standard ones are cheap. To the best of my knowledge, all 45d dizzies had push on leads.

Chris
Chris H (1970 Midget 1275)

Dan,
I don't know how much you have been quoted for HT lead sets, but you can make up your own from copper core lead, for about 2 quid a metre. It's all I've ever used on mine. Very easy to do.
Lawrence Slater

well i was looking at Cobalt High Performance HT Leads from moss.

sorry if im not ment to post links

http://www.moss-europe.co.uk/Shop/ViewProducts.aspx?PlateIndexID=6345
D Sartain

Before I converted to electronic ignition I too made my own leads from copper cored wire. Looked good too with yellow and black striped wire and NGK connectors. However, copper cored wire is not recommended for electronic ignition systems as it can interfer with the electronics.
Chris H (1970 Midget 1275)

Yup that's a possible downside with unsupressed copper, but I thought only if your runs are too close to the electronics. And these aren't modern computer chip controlled engines. Maybe the K series might have a problem though?

I suppose it depends on the type of electronic ignition system you install.

I had an Aldon, all in the distributor kit, fitted for a while in my 25D4. No problem at all. I use resistive Bosch caps, so don't/didn't get a problem with interferance.

Anyway, I've gone back to points again now so I'm back in dinasoar land again it seems. :)

Dan,
the leads you posted about aren't too badly priced, and as they have a lifetime warranty, seem a good buy.

Worth seeing if anyone can back up the claims though, before you shell out the dosh.
Lawrence Slater

Thats what i was thinking really with the lifetime warranty but its the point about changing to top entry dizzy cap as the clearance isnt enough for me to do that.

Might just have to order them and then if wount do send back anyone had any problems sending back things to moss.
D Sartain

if you have a side entry cap with piercing screws then you could just take the end connectors and sleeves off the new HT leads – subject to the lead not being too thick to slide inside the dissy cap “arms”

of course if you do this there’ll be no return to supplier possible

remember to burp the sleeves all ends if the are tight

again the HT lead set is the sexy bit but more important to get the most out of them is to have a dissy cap and rotor of good quality and in good condition

Dissy Doctor –
http://www.distributordoctor.com/red-rotor-arms.html

http://www.distributordoctor.com/distributor_caps.htm
Nigel At

no problem with getting side-entry push-in caps for a 45D, although new they are mostly screw-attach and need a little mod if your dizzy uses spring clips. Either Dave O'Neill or I can supply you one (mine ar ready-modded) - sorry for the plug !
David Smith

well long story about the cap it was replaced last serivce £12 and yes your right it is a screw in but its a spring clip dizzy lucky that it didnt need any modding im more asking could the reason be them saying that the fact that the ends cant go onto a side entry cap because of the angles of the lead it may block a hole for another lead. its side enty they are saying the problem and needs to be top entry.
D Sartain

Dan,

I'm not too sure about using screw piercing caps on this type of lead.

Whereas, in the original side entry cap, the screw pierced the outer insulation and made solid contact (or not) with the copper core, it could be a bit hit and miss with this type of lead, and may damage the core.

I think the core of this type of lead has to be terminated properly into a metal sleeve.

However having said that, if the temnial sleeve is not too wide, it might be possible to insert this into the cap, and use the screw to retain it. But I think they are actually designed to be an interference fit rather than be pierced. i think there are two types of side entry cap. Screw piercing and interference. I have the screw type.


I'm only surmising here, so if someone has actually done this could they correct me?

As Nigel says, if you do alter them in any way, you won't get your money back, so best find out first. :)


Lawrence Slater

Dan, last post unintelligible - try punctuation please.
David Smith

Dan,
IIRC the side entry cap was used to take the leads away from the steering rod so it’s a matter of space as to cap and/or whether 90 degree right angle HT lead connectors are required

I hope the photo comes out large enough to show what I mean

As said earlier you can get leads you cut to the lengths and fit the end connectors you require

Lawrence,
the photo shows my old dissy with side entry cap that had piercing screws and skinny silicone leads that I fitted, all seemed to work well (Aldon igniter fitted too)

David,
there are two full-stops :)


Nigel At

Cheers Nigel.

That confirms that you can probably use the Moss leads with the screws then Dan.

But of course, you will lose your lifetime waranty ( I assume they are meant for interference insertion rather than screw piercing). So it might be better to get a "self made kit". Probably cheaper too.
Lawrence Slater

you neither want nor need to be messing around making leads up and butchering things. Buy a set of push-in leads, buy a push-in side entry cap, spend 2 minutes fitting them - then go and enjoy a long drive with all the time and effort saved


David Smith

Blimey David that looks like the type of thing that you'd find gracing Lawrence's engine ! :)

you'd want 90 degree ends for that

so what's the part number for a side-entry dissy cap to fit a 45D
Nigel At

I don't know what all the fuss is about. My leads have right-angle ends and are a push fit into a side entry dizzy with no problem. As David Smith says, 2 minutes and you are up and running!!!
Chris H (1970 Midget 1275)

or you can have unnecessary right angle ends such as here


Nigel At

This thread was discussed between 18/09/2011 and 20/09/2011

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