Last night went to Cruise Night with a good friend and his 440 Coronet convertible.

As soon as we pulled in after a 30 mile drive, his car died out. A quick check and we discoverd the fuel pump quit (btw, recently replaced).
Luckily a friend has one and he had his son swing it over to us (Thanks Scott (SCRAG) )

Get the pump in and now we had fuel but lost spark.
After making checks, come to find the Mallory Unilite module in the Mallory distributor had toasted.
The only thing we had done to the distributor prior was disconnect the connector to disable ignition when checking fuel.

His ignition system is comprised of the Mallory Unilite Distributor, MSD 6AL and MSD HVC Ignition Coil.

I had a similar experience last year with my dad's '67 Barracuda. It had a Pertronix kit installed prior (not by me). We had just finished swapping a 4 barrel intake and carb. I needed a hot ignition key on wire for the electric choke. I was checking with a test light at the ballast resistor. Found what seemed to be a good wire and tapped it.
Now the car wouldn't start. Later to find out I must have wiped out the pertronix module while checking for a hot wire.

Any thoughts on the Mallory Unilite? My friend is deciding whether it is worth keeping it and keeping a $100 unilite sensor as a spare or just put in another distributor.

Thanks!

I thought the unilite was an all-in-one unit (no box required)... why the MSD box?

Unilite is a complete electronic ignition set up, but many, including myself, add a MSD box for the same reason as everyone else, it makes the spark hotter. I love the unilites and wouldn't run anything else. As with any product some love it some hate it, I have run them for 25+ years including just the under cap converters, the only problem I have ever experienced is the rare occassion were I cause it myself, similiar to your experience. IF your friend goes with another dist, I would be interested in having his old one as a spare.

I have the unilite in my Bee along with a Mallory coil both installed in 1976. No problems with it at all.

Hey, thanks for the positive notes on the distributor I'll be sure to pass it on to him.

Mopar346, how do you think you may have caused the ones fail that you touched? Just cutrious to know how to avoid that again.
I'll be sure to let him know your interested if he decides on some other distributor.

Thanks again and keep the comments coming

The only way I have ever blown a module is by shorting it out, I haven't done it often and it has been years. When I am going to do anything with the wiring that is related to the dist in any way I simply unplug the 3 wire connector and double check all my wiring before I plug it back in, when installing one I do the same thing, leave it unpluged and wire everything, double check everything and plug her up, tune the key and it goes vroom vroom, no problem. Best bang for the buck you can do for a car.

IMHO, using a light to trigger your ignition isn't very good.........They just aren't consistant and look terrible on a scope......You don't ever see them on anything really fast and nothing from the factory has anything like it......I only use them as wheel chocks......

hey Mopar346, thanks. I totally understand about leaving it umplugged until the very end when you are sure it is all good. Thanks!

Big_squeeze, I didn't use the test light to trigger the ignition, but to look for a hto wire with the key on. I normally wouldn't use a test light on a modern electronc equipped car, but looking for power on an old car. Thanks for pointing that out anyhow.

I don't think Big Squeeze was saying you souldn't have done it, he was just giving his thoughts on a light activated ignition. Hey Big Squeeze is your avitar running with scissors or a 4 way lug wrench???

The unilite modules do not like voltage spikes and they recommend you add their inline filter to avoid the spikes.

A friend of mine has been running a Unilite on his '72 Chevy for the last 15 years. Not one problem.

Screecher's been running a unilite in his Dart for years.... no problems. Do you have it hooked up to a full 12v source? If you're running the ignition from a resisted down lead, it could lead to problems.
-resisted lead to coil.
-full 12v lead to ignition.

RobbMc on this board turned me on to the Mallory E-spark,which is a direct replacement for the Unilite module,at HALF the price!I purchased 2 from Summit Racing just so I could keep a backup in the glove compartment.They are the exact same internally,only difference is the marketing,and have same connectors and are the same size.
Mallory modules do not like voltage spikes of any kind,mine burnt out because I had a battery charger hooked up trying to start the car.As far as someone on this board saying that fast cars never use Mallory Unilite;that's completely untrue.

Define "really fast", I have run low 10s with them, in more than one set up, of course I'll spray the crap out of one too.

Yea, I can see scissors and the 4 way.

Hey everyone! Thanks again for the additional insight and suggestions, much appreciated!

Thanks for the power filter suggestion. That may have been the cause. I was reading the description of the filter and it is highly recommended for cars with ballast resistors.
I remember seeing a ballast on his car and I think I now know how it got damamged. I remember after repairing the fuel pump we tried starting it but the unilite connector was off. Se we reconnected it but I think the key was ON when it was connected which could have created a spike on the initial connection.

Thanks for the E-spark suggestion as well. I was wondering if that would fit and be a cheaper substitute spare. Thanks!

I run a points distributor with the mallory e spark conversion. I swear by it. Made it a whole different car. Runs like never before,starts easier and the car is overall more driveable. Id reccomend one to anybody No problems whatsoever!!

Thanks again everyone!

I showed this post to my friend and he became a believer instantly.
He purchased the surge protector and a back-up unilite sensor.

Thanks again!