Chrome box melted

[nitrohemi]

I have a chrome box on my 67 gtx hemi. been there since the early 90's the other day i see the gel has melted out the back of it and is running down the firewall. any idea why that would happen? Is the box still good? never seen this before. Maybe i'll go back to points since you cant get the gold box anymore.

 

[Oldreddodge]

Did you leave the key on for a long time without motor running ? it gets the box hot,I’d keep a spare handy,

 

[Andew Sury]

First thing I did with my 67 was go Pertronix on the original distributor. Module, coil, and a bypass on the resistor.

 

[Jerry Hall]

First thing I did with my 67 was go Pertronix on the original distributor. Module, coil, and a bypass on the resistor.

I have run pertronix on several cars and never bypassed the resistor. Please tell me why. Mine were older Pertronix systems and the instructions didn't say anything about that.

 

[Daves69]

Some of these deteriorate over time. A post I read said it was due to the "mix" between batches if I recall. This one, not a chrome, leached out just sitting in a box for years......

 

[Jerry Hall]

I have a chrome box on my 67 gtx hemi. been there since the early 90's the other day i see the gel has melted out the back of it and is running down the firewall. any idea why that would happen? Is the box still good? never seen this before. Maybe i'll go back to points since you cant get the gold box anymore.

If it hasn't quit yet it will soon. If I had an original dual point, I would go back to it. I replaced my chrome box about 5 years ago, but have since acquired the dual point I wanted, so when the next chrome box goes out, the dual point goes in.

 

[RJRENTON]

If it hasn't quit yet it will soon. If I had an original dual point, I would go back to it. I replaced my chrome box about 5 years ago, but have since acquired the dual point I wanted, so when the next chrome box goes out, the dual point goes in.

IMHO.....HOORAY.....As I'm a proponent of originality, I have an original numbers matching Prestolite dual point distributor in my GTX. When I equired the car 35 years ago it had one of the first MSD 6C systems.....which I removed and put in the Prestolite system and never looked back. I'm sure the MSD boys will have their own opinions and preferences.... Just my opinion of course.
BOB RENTON

 

[Bobby Sixkiller]

It’s pretty common for the gel to run out of the box. Sometimes they still work. Sometimes they don’t

 

[1 Wild R/T]

Some of these deteriorate over time. A post I read said it was due to the "mix" between batches if I recall. This one, not a chrome, leached out just sitting in a box for years......
View attachment 853796

I have a chrome box I bought new in 1978 from Poway Dodge that did exactly that... Sitting on a shelf in a box & the potting material melted.... It worked when I set it aside so I bought some modern bedding epoxy & re-poured the bedding... It still works fine...

 

[Jerry Hall]

I have a chrome box I bought new in 1978 from Poway Dodge that did exactly that... Sitting on a shelf in a box & the potting material melted.... It worked when I set it aside so I bought some modern bedding epoxy & re-poured the bedding... It still works fine...

That's good to know.

 

[threewood]

I have run pertronix on several cars and never bypassed the resistor. Please tell me why. Mine were older Pertronix systems and the instructions didn't say anything about that.

The Pertronix II and III state in the instructions that their modules need to see full 12v so they say to bypass the ballast resistor and use their Flamethrower coil. I have both systems and both I've been fantastic.

 

[72RoadrunnerGTX]

I have a chrome box on my 67 gtx hemi. been there since the early 90's the other day i see the gel has melted out the back of it and is running down the firewall. any idea why that would happen? Is the box still good? never seen this before. Maybe i'll go back to points since you cant get the gold box anymore.

The breakdown of the original potting compound has nothing to do with the function of the electronics unless significant moisture is allowed to get to the internal components. I have seen the original potting compound breakdown on units never exposed to excessive heat, in storage and in their original boxes. If it still works, seal it back up with a modern epoxy and run with it.

I’m in to originality as well, but you couldn’t pay me to run any version of an ignition system based on the use of mechanical breaker points switching, too many way better modern alternatives available today.

 

[Andew Sury]

I have run pertronix on several cars and never bypassed the resistor. Please tell me why. Mine were older Pertronix systems and the instructions didn't say anything about that.

Jerry, I bought it as a kit direct from Pertonix and that;s what the instructions said. I've done a few dozen at my shop in other makes and they ask asked for a full 12v volts. GM points are a pain in the *** as they use a hidden resistor wire for the coil.

 

[Jerry Hall]

The Pertronix II and III state in the instructions that their modules need to see full 12v so they say to bypass the ballast resistor and use their Flamethrower coil. I have both systems and both I've been fantastic.

Thanks, I have not ran the II or III, but have used their coil.

 

[nitrohemi]

The epoxy is just soft. Maybe from just being old. last i ran it the box wasn't hot but the epoxy was very soft. I think I may pull the chrome box off and take a look at it. I have an orange box that I got with the electronic kit that I keep as a spare. probably form the early 90s or late 80's. still on the fence about going back to points. may end up doing that in the long run.

 

[Bobby Sixkiller]

Dug one out of the toolbox on my old truck once. Had a spark plug wire melted into the jelly on it. It got me home

 

[Sixpactogo]

When the Chrome box first came out years ago, I remember reading that they were meant for race only and not for daily drivers. I really have no clue as to why it was but may have something to do with being energized for long periods (like a 200 mile trip) overheats them.

 

[RJRENTON]

When the Chrome box first came out years ago, I remember reading that they were meant for race only and not for daily drivers. I really have no clue as to why it was but may have something to do with being energized for long periods (like a 200 mile trip) overheats them.

There are several semi-conductors that are internal to the box. The programable device that interprets the reluctor pulse is constantly being switched on and off at a changing rate (RPM of the distributor). This device controls the transistor on the outside of the case, which switches the coil current to create the spark. If the owner decided to use a non recommended coil, or a non recommended application (everyday driving), the situation is exacerbated. Higher internal current leads to higher internal losses (heat or I2R losses), will eventually melt the potting compound. Just my opinion of course.
BOB RENTON

 

[nitrohemi]

There are several semi-conductors that are internal to the box. The programable device that interprets the reluctor pulse is constantly being switched on and off at a changing rate (RPM of the distributor). This device controls the transistor on the outside of the case, which switches the coil current to create the spark. If the owner decided to use a non recommended coil, or a non recommended application (everyday driving), the situation is exacerbated. Higher internal current leads to higher internal losses (heat or I2R losses), will eventually melt the potting compound. Just my opinion of course.
BOB RENTON

Good to know. its been on there for 30 years. probably only a few thousand miles. old mallory voltmaster coil from the 70's. maybe its time to replace everything

 

[Jerry Hall]

Good to know. its been on there for 30 years. probably only a few thousand miles. old mallory voltmaster coil from the 70's. maybe its time to replace everything

If it ain't broke don't fix it. IMO