Practically Classics Forum

Hi Folks
had a problem with mis-firing MGBGT(1968),drove OK but mis-fired intermittently.have changed everything, (red rotor,points, condensor,timing adjusted,thought I would change coil,(no ballast) used spare one, drove for about 500yards and engine cut out, then non starting. Coil got verrry hot so obviously wrong coil!!!!! can`t now get anything to points or ht to dist.Thought I may have blown condensor, new one made no difference.have I blown something else? Got power to HT lead at coil, fitted a new(correct one), I have checked everything I can think of, am I missing something?(Fuel is getting through)
Ron

new one made no difference

Edited 18:47 to include "IF this is a condenser issue".

Not surprising, they tend to be poor though a good source of teflon or poly ones can be found from eBay seller's shop "Sovcom". Go for a 1uF one but buy two in case it needs closer to 2uF and then you can connect these in parallel. 630WV rating is fine for this purpose but sadly, no currently available car-specific capacitors can be trusted, we have the students hollowing cans out and packing them with the new ones in cases where they want to preserve original appearance. I, on the other hand, would just as soon fit an MM electronic ignition kit which costs only as much as one set of contacts and a couple of decent Sovcom capacitors or, if the lesson involved staying with the points, I'd fit the caps externally using a couple of brackets peeled from original internal ones.

PM me if you'd like a couple to try, gratis as we get these by the hundred and make their cost back by the twentieth one used!
I'll be in the UK most weeks between now and the end of summer term.

Hi John, thanks for reply, everyone speaks about Distrb. Doctor parts and that is what I have used, but will give thought to your suggestions and check MM elec Ignt.

The source you mention was once a good place to go looking for quality ignition components and indeed, when they started out selling such things, I would have recommended them but following a successful action against by the legal team working for the LEA that employs me vs a supplier that may or may not be them , I couldn't possibly say more. Not publicly, that is.

MM4x4 supply the system under their Britpart name, they're cheap and I always advise people to buy a couple (though MM are always happy to exchange faulty ones, unlike certain ignition parts suppliers whose ignorant, rude and at times downright abusive staff will insist that the customer is always wrong) but, and here's the thing; the Britpart from MM tends only to fail in much hotter environments than a B's engine bay (think small, GRP panelled and with a Reliant badge) and they're at least as reliable as Pertronix/Aldon "Ignitor" systems which cost around eight times as much even if imported from California directly by the end user.

Incidentally, the system sold by eBay vendor "Simon BBC" is the same thing that you can get from MM at far, far below his price. In fact, if you know another 599 owners of cars with 43D or 45D distributors, the systems can be bought directly from the Chinese factory at 62p each. (Minimum order quantity 600 you see).

Check your engine earth lead is tight and the connections are good at both ends, it doesn't cost anything to do and this fault caused this exact issue on my 79 Scimitar GTE

Ian wrote:Check your engine earth lead is tight and the connections are good at both ends, it doesn't cost anything to do and this fault caused this exact issue on my 79 Scimitar GTE

. . . . and on my sons Mini - the so called rebuild experts hadn't fitted one so it was trying to earth through several other places instead - and whilst I'm having a rant - they cut off part of an adjustable Hi-Lo suspension unit to make it sit lower, there wasn't a split pin in the hub castle nut, and the latest only discovered yesterday is that there's no breather pipe on the petrol tank . . . . . .

Tried a new rotor arm yet?

Thanks Guys, all noted, have`nt checked earth strap, will do, have replaced rotor(couple of times),the problem now is getting spark to points/distributor, all new points, rotor,condensor, dist. cap, coil, I am sure it is something "seemple" but just can`t find it.

Checked earth strap, it`s fine,struggling now.

my 77 bgt used to break down for no reason & have non starting issues.. a very nice man from the rac traced the fault to a whatsit resistor thingy built into the wiring loom.. sorry i cant be more helpfull it was a while ago & my memory isnt what it was...