MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - Longgevity of pertronix

About ayear ago I installed the pertronix kit into my 1974 MGB. It went very well. The only reason I did not do it sooner was that the points set-up worked just fine. The change required removing the points and condenser. I think changing back to points would be more difficult than just replacing the pertronix unit. Anybody Know how long They last? Has anybody had difficulity keeping their car going with pertronix? Can they last about forever in a car thats properly maintained? I'm just wondering if I need to keep a spare. Thanks Bob
Bob Ekstrtand

Bob

I have had a Pertronix Ignitor in my 58 A since May 1997 and it hasn't missed a beat. That said, there have been a few instances reported where there have been failures, cause unknown. To be really safe carry a spare mounting plate with the points and condenser in your "spares" bag.

For more information browse the MGA and MGB archives. To do this you need to be a member. Its free.

HTH

Larry
San Diego
Lawrence Hallanger

I had been running a Pertronix in my 1972 BGT and thought it had failed because reinstalling the points and condenser got the car running. When it failed to start a few days later, I actually checked the car out and found the battery had a bad cell. After replacing the battery, I put the Pertronix back in and it worked as good as before. It appears the Pertronix unit really wants to see 12.5V.
John Perkins

There are no moving parts in a Pertronix, so theoretically it could last forever. That said, I too, carry a mounting plate with preset points and condenser as a spare (the only time I was ever stranded on the road was due to a Hall effect ignition system (same as the Pertronix) failing. Cheers - Dave
David DuBois

I have had 3 go bad in the last 6 years!
Save your receipt.
Keep the points & tools in the car.
Len Fanelli

"There are no moving parts in a Pertronix, so theoretically it could last forever"

I wish, in that case *all* electronics would work forever, but as we know they don't. The problem with electronics is that when they fail they usually do so totally and suddenly, and can only be diagnosed by replacement. Points, in the distributor and the pump, are much more forgiving.
Paul Hunt

I have a document that I got from Pertronix to show the correct test procedure for their ignition systems. If you would like a copy, please send a note to my email address.
John Perkins

I had a problem with this electronic ignition too on the roadster. It was one of the magnets that failed and I am back on points again.
Just calculate a set of points and a new capacitor every 24 month and ask yourself how mutch the electronic ignition can safe for you ;-)
If you still want to go the electronic way, you can also fit one of the old fasion external electronic ignition modules and the points will not wear out any more as they only have to deal with a very low current then.
You can also put a switch to such an installation to run without the electronic in case of a problem.

With my SD1 engined GT, I went to two Lucas Opus distributer breakdowns caused by engine heat within the years and switched to the Newtronics optical system some years ago, as the Mallory dual point was an uneconomic alternative. With the Blackbox ahead of the radiator it seems to last...

My conclusions are:
Electronic ignitions are fine (but expensive), as long as they do not fail mainly caused by overheating.
If you want to use an electronic ignition, try a black box system using an optical trigger or keeping the points and find a well ventilated place to mount it.
If you want to keep your money and avoid a brake down risk due to electronical ignition problems, stay with the points and check the system at intervals.


Ralph

My Pertronix ign conversion has been happily working for
about 8 years.

When I swapped to their high voltage Flamethrower coil
my dizzy rotors began to suffer premature deaths due
to shorting out. I went through 3 of them.

I stopped killing dizzy rotors when I swapped to a Bosch
Blue Coil. It has higher voltage than stock, but lower voltage
than other high performance coils.
Daniel Wong

I used to work in a forklift shop where we had Mazda engined machines. These were carton clamps for loading trucks. We converted to Pertronix systems and had nothing but trouble. We had a shelf full of coils and took one with us whenever one would die. If it died in the back of a truck I would pop the cap and rotor and hole the coil in my hand for a minute reassemble and most times I could get the machine out of the truck. I believe the heat caused the coil to openup, holding it in my hand cooled it enough to close for a short time. We went back to points. I had an Alision system on my GT but it now has points.
J Schiessl

I've had my Pertronixs in my B for 12 years! No problems...i do carry a spare pertronixs in case it goes...saw no need to go back to points ever...why I went to a pertronixs in the first place!
Bob Dougherty

Thanks Bob, I was hoping to hear that! I appreciate all the input on this question. Bob
Bob Ekstrand

Hope I don't jinx myself, but 10 years trouble free.
Phil Collura

I believe my first Pertronix managed 12 miles and the replacement they sent me did manage a bit further at 350 miles. Never actually found out why they failed, but when they did it was a quick stop, no chance to struggle on under mis-fire as you can with points system. So always carry a backup as I was fortunate enough to do. Although mentally wounded by the failure, after the thought of maintainence free ignition, I still persue the idea and have now fitted the 123 distributor, but still carry my trusty 25D4 with points.
Graham
G Cherry

Magnetic pick-up failed after 10-years (+/-) in our '74 B/GT with (45D). We lost a pickup magnet when the assembly cracked (heat). This also happened to another club member a few years ago, be it in a TR-6.

We replaced the distributor with a new Petronix Flame Thrower, and what a difference this made in starting, and smoother performance. No connection at all with the company, but would recommend to anyone with a worn distrbutor.

Regards,

L.C. '74 B/GT & '69 midget
Larry C '69 Midget

I just heard the other day about a problem with the add-on electronic modules that still use points. As was mentioned above, the points don't spark much anymore, so they last a long time. But since they don't spark, they also don't burn off a bit of oil, and tend to not contact so well after a while. Easily cleaned, but still a pain on a rainy day.
Tom

This thread was discussed between 26/03/2009 and 01/04/2009

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.