Mallory Unilite Help...Pulleezzzeee
Thread Starter
Racer
Joined: Jan 2002
Posts: 293
Likes: 2
From: Warrensburg, MO
Mallory Unilite Help...Pulleezzzeee
Ok, you electron guru's, I'm beggin'. I've got a Unilite with a Hyfire 6AL box. Was working great, then started shutting off after idle for 2-3 minutes. Now it won't fire at all. I've replaced the Hyfire, and hooked it up the same as the previous one...no fire. I tried bypassing the hyfire and still no spark. I've used different coils, no change. I'm stumped.
I've got 12.5 volts going to the pos of the coil and the red wire of the distributor. Likewise, I've got 12.5 volts on the green wire out of the distributor that goes to the neg terminal of the coil. However, there's no voltage accross the coil from terminal to terminal (+ to -) in either configuration with the Hyfire and without. On a different motor with a Pertronix, I get 9 volts accross the coil with the same test.
The cap and rotor both look fine. Before I replace the distributor, shouldn't there be voltage accross the coil witht he ignition on? Any ideas or further tests to determine my problem would be greatly appreciated. Thanks.
Jimbo
I've got 12.5 volts going to the pos of the coil and the red wire of the distributor. Likewise, I've got 12.5 volts on the green wire out of the distributor that goes to the neg terminal of the coil. However, there's no voltage accross the coil from terminal to terminal (+ to -) in either configuration with the Hyfire and without. On a different motor with a Pertronix, I get 9 volts accross the coil with the same test.
The cap and rotor both look fine. Before I replace the distributor, shouldn't there be voltage accross the coil witht he ignition on? Any ideas or further tests to determine my problem would be greatly appreciated. Thanks.
Jimbo
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Better yet put a Pertronix conversion into your Mallory distributor. I dealt with Unilites back in the 70's when I was working my way thorugh college in an auto parts store, lots of Unilite failures back then including one in my Boss 302. Had a 3 mile walk because of it, won't ever use one again!
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
Better yet put a Pertronix conversion into your Mallory distributor. I dealt with Unilites back in the 70's when I was working my way thorugh college in an auto parts store, lots of Unilite failures back then including one in my Boss 302. Had a 3 mile walk because of it, won't ever use one again!
BUT, I only use it to trigger my MSD-6AL ignition box, so only a very small current goes through the module.
Melting Slicks
Joined: Mar 2007
Posts: 2,100
Likes: 12
From: Frederick Maryland
A voltage spike can fry the module in a Unilite. Mallory sells an inline spike filter to prevent that. To me, if the problem is prevalent enough to make a filter to prevent it, Mallory should design the filter into the distributor or supply it as standard rather than make it an extra cost option. That's simply good customer service...it's easier than trying to regain customer loyalty once its lost.
Advanced
Joined: Dec 2008
Posts: 52
Likes: 0
From: Medina Ohio
I have never had any luck with anything from Mallory especally the Unilite Distributors. I have 2 hanging on the wall that I never got working. I know others will jump all over me for stating this but that is my history with the company and there products. My suggestion and this is only a suggestion is switch to MSD.
CF Community Team
Joined: Oct 2004
Posts: 19,367
Likes: 5,244
From: Cape Cod, Mass.
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It's the module. I have Mallory Unilites in both my 61 and 65 and have had module failures in both. I'm sticking with points in my 68. There is a filter that Mallory sells to soften the electrical pulses to the module. That may help prevent future module meltdowns.
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Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Anyone needing a cheap Unilte module, I have a few spares from a Vette I bought a few years back. $30 each, Email me at zeohsix@gmail.com. I'll test them on my friend's Sun machine before shipping but no guarantees!
I wouldn't wish one of these on a Mustang owner
I wouldn't wish one of these on a Mustang owner
Thread Starter
Racer
Joined: Jan 2002
Posts: 293
Likes: 2
From: Warrensburg, MO
Thanks for the words guys. I'll be getting a new module directly. The Unilite and Hyfire have been doing the job for 8 years on the race car, and my lousey wiring probably caused the failure (did have a lose wire on the switch panel). I love the built in rev limiter, and the fact that when working, it fires after 1/2 second of starter rotation. The only problem is that the diagnosis matrix has you checking the voltage accross the coil while interupting the opti sensor. Mine has no voltage accross the coil, but does to the green wire which attaches to the neg of the coil. That's what threw me.
Jimbo
Jimbo
Melting Slicks
Joined: Jul 2001
Posts: 2,609
Likes: 12
From: Massapequa Park NY
Anyone needing a cheap Unilte module, I have a few spares from a Vette I bought a few years back. $30 each, Email me at zeohsix@gmail.com. I'll test them on my friend's Sun machine before shipping but no guarantees!
I wouldn't wish one of these on a Mustang owner
I wouldn't wish one of these on a Mustang owner
Have a Unilite in my Mustang for the past 16 years with no problems. Sure does sound like the module went bad.Jim
Drifting
Joined: Jul 2002
Posts: 1,697
Likes: 3
From: Woodinville WA
This is the module I use in my Mallory Unilite: Summit Link, It is $40 instead of the $80ish one from Mallory.
Pro
Joined: Apr 2008
Posts: 596
Likes: 6
From: Irving Texas
Another thought:
I have a Mallory magnetic distributor with no problems but listen to this:
My buddy buys one. He removes the cap to look inside. He goes to put the cap back on.
He ***** the cap to one side as he trys to snap it in place.
The little carbon button snaps off.
This button is designed to move in and out, but not flex.
If he had installed it, everything would look right but the button would have never touched the rotor.
Just sayin.............
I have a Mallory magnetic distributor with no problems but listen to this:
My buddy buys one. He removes the cap to look inside. He goes to put the cap back on.
He ***** the cap to one side as he trys to snap it in place.
The little carbon button snaps off.
This button is designed to move in and out, but not flex.
If he had installed it, everything would look right but the button would have never touched the rotor.
Just sayin.............
Drifting
Joined: Jul 2002
Posts: 1,697
Likes: 3
From: Woodinville WA
Another thought:
I have a Mallory magnetic distributor with no problems but listen to this:
My buddy buys one. He removes the cap to look inside. He goes to put the cap back on.
He ***** the cap to one side as he trys to snap it in place.
The little carbon button snaps off.
This button is designed to move in and out, but not flex.
If he had installed it, everything would look right but the button would have never touched the rotor.
Just sayin.............
I have a Mallory magnetic distributor with no problems but listen to this:
My buddy buys one. He removes the cap to look inside. He goes to put the cap back on.
He ***** the cap to one side as he trys to snap it in place.
The little carbon button snaps off.
This button is designed to move in and out, but not flex.
If he had installed it, everything would look right but the button would have never touched the rotor.
Just sayin.............
Drifting
Joined: Dec 2009
Posts: 1,349
Likes: 34
From: Porterville Ca
Used to sell parts. We sold unilite modules to the unlucky, usually when their pride and joy died on what was supposed to be a great weekend. Funny thing is that those six or eight customers have scarred me for life, my "BABY" is getting a MSD and a "6" box. I didn't even consider a Mallory for MY pride and joy.
CF Community Team
Joined: Oct 2004
Posts: 19,367
Likes: 5,244
From: Cape Cod, Mass.
2025 C6 of the Year Finalist - Unmodified
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2020 Corvette of the Year Finalist (performance mods)
2019 C1 of Year Winner (performance mods)
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Glad you got it fixed. Enjoy the ride.
