(Electronic) Ignition issues...

[BDN712V]

I've had no end of issues with my ignition system in the last few months... Initially I was running a conventional system (in my 1500HL) with 6v coil, ballast resistor etc. BUT using a 1300 starter & ring gear (long story...). This type of starter does not have the additional bypass contact to supply the full (!) 12v to the coil when cranking, and I cannot find a way of taking it off the solenoid easily. HOWEVER, it was working very well, firing up almost immediately.

First problem was the condenser coming away from the points (the soldered joint gave way) giving intermittent cut-out of the engine. I swapped this out as soon as I traced the issue, and it ran well. However, occasionally it had very limited power, as though only firing on two cylinders. Diagnosing the issue took a lot longer as it was not a consistent failure-to-fire. In the end I discovered that the feed to the coil was damaged (the white/yellow wire was broken about 1" from the lucas connector onto the coil...), so I bridged it out with a new wire from the fuse box to the coil, with ballast resistor, and lead ready to be fed from the 'unballasted' feed from the starter / solenoid, depending upon which type of starter was fitted by that stage...

This is where things got messy, as I also took the opportunity to replace the coil (excessively high resistance on the secondary side compared to the specification) and fit the magnetronic ignition system, with feed from the feed side of the fuses. It now does not want to fire at all.

My next step is to see where I have voltage... BUT I have a question. Is there any way of testing the ignition module in itself, easily, or is it a case of checking I have power to it, and something from it to the HT leads?

[Jon Tilson]

Think about what happens with points and a magnetronic is supposed to do something similar....

So look at the coil minus. Here you would expect to see 0v as the points are closed and high volts as the points open.

So if you have an analogue meter you can put it on coil minus, turn it over and you should see the needle going up and down. If you don't
then the magnetronic is not doing any switching.

If it does then you need to work out the firing point...volts going up...and set it accordingly by moving the distributor.

If it works you can do away with a ballasted system.

Jonners

[BDN712V]

I seem to be running into further problems with this...

I currently can get a very poor spark with a 12v coil fed from the ignition (using the king lead to the battery negative to judge). Using a 6v coil and ballast resistor produces a very hot ballast resistor and virtually no spark. Using a 6v coil without ballast resistor gets the coil very hot but a good spark.

I have put a new feed from the ignition switch side of the fusebox to the coil as the previous wire was defective, giving an intermittent fault. I have had meters on everything and am currently using points and condenser. The coil gives some sort of a spark when the points are broken, so everything seems to be working... As either the ballast resistor or the coil is getting so very hot, is there anything I can try to find the problem; it seems to suggest I'm drawing too much somehow...

[Jon Tilson]

Your condensor sound like its shorting the coil to some extent.

Just get a maplin kit and do away with it.



Jonners

[Toledo Man]

Or a Britpart...

[RobSun]

I have been having issues with hot coils and miss fires on my 1300 dolomite for over two years which I hope has now been sorted.

You say that your car has a 1300 starter with no 12v start bypass. Mine has, it goes from coil + to the solenoid.

Mine was fitted with a Lumenitions Magnatronic system. Problems started with hot failing ballasted coil but the supply from the loom was not ballasted. Easily resolved with Megaspark 3 coil and ballast resistor wired to a new 12v supply. Ran for 11 months then started missing and coil over heating again. Sort advice here on what the best coil I should get and got both helpful and unhelpful comments. 12v coil was recommended by Moss with no ballast, and others, this started to fail after 2 weeks. Took the car to a classic garage told wrong coil. They got the Megaspark 3 swopped foc and all OK for 10 weeks or so, and then problem starts again with worse miss fire.

The garage then spent a fair bit of time on it all foc to rectify. Plugs, leads, cap (see my post on dodgy caps) full check of fuel system, clean, and reset up carb. Problem persisted, the ignition system was never considered because of its reputation of reliability and it works or doesn't, no in between. A discussion was had and a similar problem was recalled concearing an mga with hot coils that was eventually sorted by replacing a partly broken engine earth. My earth was duly modified from straight to battery - to chassis and then to battery with new cables. Whilst the cables were being made up I cleaned out the metal shavings from the distributor(see other post) and found the electronic unit to be red hot. It was removed and the lower face of the mounting plate was black from tracking to earth.

The car is now on points and condenser, the Megaspark3 coil has been retained and is now running as it should.

I don't know and nor does the garage if the unit was faulty or if it was engine earthing that was causing all the problems, I'm sure someone will come up with the answer, but it could be worth checking yours. My ballast resistor also gets very hot and I have queried if this is OK and been told that it is, is normal and why they have the ceramic coating.

If you have recently replaced the cap it would be a good idea to check that out for the rotor cutting into the poles and producing metal shavings that will cause tracking. The garage has worked recently on a members sprint that had a hole melt in its cap because of this problem.

[BDN712V]

Thanks again for your thoughts!

I reverted to 'standard' parts to try and figure out why it wasn't working; these all seem to be behaving. I've got the magnetronic ignition kit at home for testing now, to see what's what.

The inside of the distributor cap has no signs of any foreign bodies (!).

The (negative) earth leads are in good condition and making sound contact. Under test conditions I simply bypassed them straight to the negative terminal of the battery, but this made no difference. I have basically replaced all of the wiring in the ignition circuit to eliminate that, and tested it thoroughly. To say I'm puzzled is an understatement.

I will have a look at the solenoid I've got on, and see if I can steal some volts (!) and run with the (new) ballasted system. This is the only permutation I've not yet tried.

Hopefully the magnetronic unit is all right, and can be refitted, but I ought to be able to get the engine to fire and run as it is. And I can't!

[Toledo Man]

The Britpart kit I fitted is a straight swap for the points and condenser and includes a magnetic pickup ring. The kit had both a separate ring which can be used with the normal rotor arm and a combined pickup ring and rotor arm. I used the combined one and it hasn't given me a moment's bother since I fitted it. I have since found out that I'm running a non-ballasted ignition system. I only found out when I measured the resistance on my coil and it was 3 Ohms. The Britpart kit is supposed to work with existing coils.

[marko]

I'm also running one of those cheap kits with the magnetic pickup and the ring below the red rotor arm. The separate ring and the combination ring and rotor arm were actually different O.Ds so one was too far away from the pickup to work properly. The alloy base needed filing to get it close enough to work without missing like a pig.
I really want to go for megajolt but don't want to stray from the original look.

[GTS290N]

accuspark, kits for 1300/1500 and 1850

[GlenM]

accuspark, kits for 1300/1500 and 1850

I agree, they are very good value. I have one fitted to a 1500 Midget, which was supplied fitted to a new distributor and which came with the correct coil. I think it was about £90 complete.

[Yellow Banana]

Any one have any info on replacement earth leads mentioned below.

"On this particular subject one question. Has anyone else had the moving plate earth lead inside the distributor fall apart? Mine has the fabric covering frayed at one end which I don't think is helping my ignition problems. I have put some electrical tape round the frayed part to try to keep it more secure. I see in the Triumph parts book that it isn't serviced so, unless anyone knows different, you probably can't get replacements?"

[marko]

www.ebay.co.uk/itm/110980815807
Is this the better kit? It says lots about dwell etc but they all say they're great.

[GTS290N]

It's an accuspark, says so on the picture anyway.
Accuspark give a 1 year warranty, http://www.accuspark.co.uk/faqs.html.
I did have one fail, but at £35 it wasn't too painful, the one I have now has been in several years.

[marko]

The next question on this hijacked post is vacuum or not on a fast road 1500 with flowed head, bigger exhaust, high lift cam, higher compression etc. Initially starting on twin hs4 but then going to hif 38s.
They list both dizzys with the adaptive dwell but don't give any information on the benefits of not having the vacuum advance. I'd have thought vacuum advance was the way forward but if using really big carbs without enough pressure...?

Look at this on eBay http://www.ebay.co.uk/itm/111467427728
Look at this on eBay http://www.ebay.co.uk/itm/111226303389
What are people's thoughts on this? I want a fast car (for a 1500) but also drivable.