Lumby

Yea the details I could find got a bit confusing at the outset but I think i have a clearer picture now on how it should work!

I'll have a hunt around and see what the prices /options are for a replacement non-ballast; it isn't a race car so just needs to be reliable for a Sunday driver when I get it back on the road. 

12 hours ago, sr2 said:

The terminology has always been confusing. A 'ballasted coil' is one that needs to be run with an external ballast where as a 'non ballasted coil' is one that has an internal ballast.

As a quick rule of thumb the primary winding on an average 'non-ballasted' coil is around 3 ohms while a ballasted one should be approx. 1.5 ohms.

10 hours ago, Unclejake said:

And to add to the above wise words; a coil run without ballast (internal or external) will fry your points in short order.

I've stuffed points in less than 15 mins by bypassing the ballast resistor (but a quick sand gets you operational again to limp to the nearest points stockists). Others may have gotten months out of points like that though.

Thanks, I think I understand.. so given that there was a ballasted coil installed (but no sign of ballast), the risk of damaging the points would be lessened by installing a non-ballasted coil rather than going the other direction? The risk would be more if there is resistance somewhere in the system already that I can't see (i.e a hidden ballast or resistance wire), it will run badly on account of weak spark? It may mean that the points are already damaged - I haven't been running the car much as I work on panels, and i don't recall seeing damage but I will check these again to be sure.

Similarly, to fry the points the only way to achieve that would be to bypass a ballast resistor in the system? A non-ballasted coil wouldn't carry that risk on account of the internal ballast?

2 minutes ago, azzurro said:

I dont think so, unless your starter draws so much battery current that the voltage drops at the coil sufficiently that it no longer fires or has a weak spark (ie the problem the resistor was designed to fix, still exists)

 

Ahhh, and the penny drops! Thanks

Not quite so dramatic no! 

4 minutes ago, azzurro said:

(and your measure of the power at the coil was = to  battery voltage, right - ie not with engine/alternator running whcih would be 14V+ so 12v when running would imply some resistance)

The R is added to older cars because of voltage drop when cranking with older battery tech, so the coil still works, tricky bit is that it is UN-resisted when cranking (getting all the volts avalaible) but needs to be resisted when its not cranking/alternator is spinning  else it blows up

If you going to get another coil go with an unresisted set up (ie GT40, no R)

Yes the voltage measure is to battery voltage only.  I was under the impression that if a resistance wire or ballast was present, it should show ~9v at the coil connection with ignition switch open, but not cranking or running.  

Are there any issues with running a straight non-resisted set up? 

Morning all,

After a bit of a search and a google, I can't find exactly what I am looking for so hoping someone will be able to shed some light for me on replacement options/issues/implications;  

It seems the GT40R ignition coil blew in the cortina yesterday - having tested and checked other parts of the system, it seems to be the only piece that is faulting. 

The replacement options I have found state that a ballast resistor should be used - having checked through and chased the wiring as much as I can, I can't see any sign of a ballast resistor being present.  Some of the online discussions suggest that Ford used a resistance wire to drop voltage at the coil instead, but the measured voltage across the coil is 12, suggesting this isn't the case / enough changes have been made over the years that it is long gone if it was ever there. 

Am I best to simply replace the GT40R on account of it was running prior to the fault, should I switch to something like the GT40 which *suggests* 12v direct is fine through the coil or should I be looking to wire a ballast resistor inline?

Ginger settles the stomach - ginger nuts, ginger beer etc, I usually keep some ginger nuts handy if taking people of unknown constitutions on the boat but it has mixed results as once your crook its harder to fix..  My brother uses the Sealegs pills to good effect, makes big difference for him.

Have heard good things about Paihia Bombs but never tried them - they are internet order only I believe where as any pharmacy will carry Sealegs or equivalent...

Does it have to be 300 x 300? most of your landscaping depots will sell macrocarpa sleepers which are ~ 200 x 75 x 2.1 mm for about 30 bucks.  You could double it and dress it how you like and mac is pretty sweet in the ground for untreated etc....

Cheers guys, pulled the alternator off and got it to the auto sparky today.  he's just informed me that it's completely cooked and not really repairable so needs to be replaced.  He was asking if something had happened to the car because it was well toast inside - hopefully it's just wear and tear as I can't think of anything apart from maybe driving it home after I noticed a change in engine tone as mentioned above. 

Good prompt service from Coast Auto Electrix, would recommend. 

Thanks, battery terminals etc all sweet and couldn't see any issues with cables so looks like alternator is coming out Sunday to be sent off to the local auto sparky for repair / replacement.  

Thanks, except I am at work and had lunch to test for faults so was hoping for guidance in case it was something more sinister... Battery tests fine at 12, raises to 12.8 when running but drops under load to 12.65. So its faulting but not completely ruined.. have to take it out Sunday for repair / replacement next week. 

Usually   but battery light is not specific to alternator no?  just to a low voltage problem?  I have had odd fault codes out of this POS before.  Like dirty throttle body triggered O2 sensor fault code etc. so was more curious if anyone had come across similar issues as time is short for diagnostics.  

Sweet, thanks. was thinking too much.  yep voltmeter on the dash, should have checked that - was running late and not thinking.

Ta, not so clued up on testing electrics, whats the best way to check the alternator?  As shown below?

Chaps and Chappettes,

Not old school I know, but my daily decided to throw its toys this morning with what appear to be a few electrical gremlins.  Symptoms are lack of electrical power - ie wipers, windows etc all struggling to operate, and limited lights, ABS warning Light and Battery warning light on... seemed to drive okay but I wasn't going to risk it...

It ran fine to work yesterday, but when I started it to drive home, there was a distinct change in tone from the engine bay - a higher pitched whir / whine had set in. A few tests round the block and no warning lights meant I figured it was ok to drive home.. The noise seemed to go quieten right down once everything came up to temperature..

My immediate suspicion was power steering pump - checked fluids etc all seems well.. no leaks and operating as it should.  New belt was installed last service - about a month ago.

Battery is still under warranty from approx 18 months ago, new VVT installed ~ 3 years ago, new fuel pump ~ 18 months ago. 

Any suggestions on what the fault would be and best way to test?  I'm leaning towards alternator...

The less spent the better as I'm still trying to get the funds together to paint my Cortina.

Name: Carl

Location: Auckland

Cars you own:​ 1972 Mk3 Cortina

1998 Altezza (daily)

Mods to them (can be brief or detailed): cortina has 2l, headers, some lowering (on kings), and gt grill. More to come.

Link to pics (if you have some, and keep it a link to keep 56kers happy)

How you found out about oldschool: Google

Anything else you want to add: Nope