Leaking coil

Quigley1930

Quigley1930

Senior Member
I have had a hard time starting my truck recently and noticed a lack of power at higher speeds. Today my son noticed oil dripping from the coil. Would this be a cause for my troubles and what would cause the coil to start leaking? I will pick up a new coil at Brattons on Monday.

Sewall Tyler
 
Probably yes. Once the coil starts leaking it's done for. Put another coil in and you should see the starting and performance improve.
 
Original coils were tar filled. Oil filled coils that were used on later model cars were mounted with the tower and wire connections pointing upward. When oil filled coils are mounted with the wire connections pointed downward as the original model A coils were mounted, they will often leak oil out the tower, overheat and begin to fail. I've pointed out this fact here many ,many times. The oil in the oil filled coils is for the purpose of cooling the inner windings. Most replacement coils are oil filled and are also weaker than the original model A coil. I don't mind saying as I have said many, many times before that I use the epoxy filled Pertronix flamethrower coil. This is a performance coil that scares hell out of many. It does however make a noticable improvement in performance, instant starts and clean running spark plugs. Coils are rated in ohm . Six volt applications use a 1.5 ohm coil. Twelve volt applications use a 3.0 ohm version. Neither of these coils need an external resister. Its the coil that fires the spark plugs. Weak replacement coils usually give weak performance and sooty spark plugs and most will tell you that you are running too rich. Weak ignition usually gets blamed on the carburetor. The original slant pole coils were around 20.000 volt. the Flame thrower coils are rated at 40.000 volts and make a difference that can be felt in the seat of the pants.
 
The oil may contain PCBs, a toxic component of the oil depending upon when it was manufactured. Prior to 1979 it says in the article.

IBM told us to avoid contact with oil from any transformer , capacitor and etc... any electrical device of unknown date of manufacture that contained oil for cooling.

http://www.epa.gov/epawaste/hazard/tsd/pcbs/about.htm



Quigley1930 said:
I have had a hard time starting my truck recently and noticed a lack of power at higher speeds. Today my son noticed oil dripping from the coil. Would this be a cause for my troubles and what would cause the coil to start leaking? I will pick up a new coil at Brattons on Monday.

Sewall Tyler
Click to expand...
 
The Petronix coil number is 40111 for the 6v 1.5 ohm model.

As Purdy says, an oil coil will not work for long when mounted upside down. I found that out the hard way decades ago on a VW.



PCBs ? We don't need to worry about no sticking PCBs. The transformer blew up in our local DMV office years ago. Our 'stuffed shirt ' governor at the time said there was nothing to worry about and that he'd come and drink a glass full of PCBs and that the office could be kept open. Of course, since a politician said so, it must be true.
He was challenged and the office was closed for years.
 
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Thanks everyone. Purdy, I now remember you talking about this recently but the memory just ain't what she used to be. I assume you can mount the Pertronix coil with the wire connections pointed down.

Sewall Tyler
 
Smog Tech said:
Purdy, what is the model number of your Pertronic coil?
Click to expand...

Smog Tech , The box that my coil came in says part# 40611 EPOXY (3.0 OHM) This is the 12 volt version . The 6 volt version will have a different number but will be 1.5 OHM. Most good parts houses can get them. I got mine from Eastwood. I got a JC whitney catalog the other day and see that they now list them but would probably take longer to get. Several others that post here use the 6 volt version and will know the part # .
 
Quigley1930 said:
Thanks everyone. Purdy, I now remember you talking about this recently but the memory just ain't what she used to be. I assume you can mount the Pertronix coil with the wire connections pointed down.

Sewall Tyler
Click to expand...

Sewall, Yes the epoxy version can be mounted the same as an original model A coil. If you decide to try one of these fine coils, be sure to get the epoxy filled version. Pertronix offers two 40.000 volt oil filled versions that shouldn't be mounted in the original manner. There is also a 45.000 volt version for electronic ignition. Take note that these coils will become warm to the touch but will really be no problem. People that probably never touched a coil after a long run will be frightened by this fact. Some that use the V8 points and condenser will automatically asume that the coil is the problem when the crappy V8 condenser or points fail. Running at high rpm or with wide spark plug gaps can cause the coil to get hotter but none of this has been a problem for me. I've run my flame thrower coil for 8 going on 9 years with no problems. All coils get hotter on long runs or higher rpm anyway. The coil delivers the spark to the spark plugs. WhenThe spark comes quicker as in higher rpm it is only natural that the coil will get hotter. Pertronix will tell you this fact if asked. I only use mine with original style points and the A&L short proof condenser that is also offered by Brattons and Snyders. I hope this info will be helpfull.
 
Benson and Patrick make a good point about PCBs . I have also read this info before and its just another good reason to avoid oil filled coils if possible. When I use to run Holly, not Holley bee hive 30.000 volt coils, they had a thin plastic housing that would easilly crack and the oil would leak out. I've got the oil on my hands before but quickly washed it off first with lacquer thinner and then soapy water. It probably didn't help me but hasn't killed me yet. I would still recommend to avoid any contact if at all possioble.
 
Epoxy filled, 1.5 ohm for 6 volt system is part number is 40111. I found the best price when I purchased mine from Amazon. I see they are $36.53 with free shipping now on Amazon. Be careful on the part number as the oil filled one has a part number of 40011.
 
Ignition coils get hot due to the current flowing though them while the points are closed. That heat has to be dissipated somehow to prevent the primary wire from becoming hot enough to open like a blown fuse. Oil is used in transformers as a vehicle to move the heat from the wire turns to the case where it can be removed by whatever means. The reason your coil clamps are so wide is because they are supposed to transfer the heat from the coil case to the clamp and (in the case of the Model A), to the firewall.

The idea of using epoxy instead of oil is troublesome. Epoxy, like oil, is not an electrical conductor, so it can be used between windings of a coil without shorting them. However, epoxy is not as good of a thermal conductor as oil, so less heat can be removed from the wire windings and transfered to the case. Even the Pertronix website mentions that the epoxy filled coils are for certain uses, one of which not mentioned is inside the very hot engine compartment of a Ford Model A. I would be concerned about the longevity of an epoxy filled ignition coil in hot climates.
 
The epoxy version is the coil that was recommended for me . The original model A coil wasn't oil filled but was a solid type tar filled coil which in my thought is similiar to a solid epoxy filled coil. All of the original slant pole tar filled model A coils that I have ever tested or used still work perfectly even after more than eighty years. It is hot under the hood of all cars, especially newer cars that run at highere temps than the model A . Model A's that are running with improper timing and gaps will have problems , no matter what coil is used. Its always easy to blame the coil when other problems exist . Higher performance V8 engines that will turn high rpm would probably be better off with an oil filled version that would be mounted with tower pointing upward. No harm meant, just thought this needed to be pointed out. Pertronix will gladly explain and recommend the proper coil for the application. People with a closed mind in regard to performance coils would be better of using a standard replacement coil for their own peace of mind .
 
Purdy, if you run the Pertronix 6-volt on a stock system do you need to use different points and condenser?
 
Ursus,

You can use either of the Pertronix coils with either original or V8 points, it really makes no difference. I just prefer the original points because they are easier to adjust and time and have been more durable in my case. The pertronix coils don't care what points that are used. They even have a 45.000 volt version for use with electronic ignition.
 
Here's a link to a recent discussion of the Pertronix Flame Thrower coil:

http://www.fordbarn.com/forum/showthread.php?t=145180&highlight=40111

To paraphrase H.L. Chauvin from that thread the Flame Thrower "will burn the hair off a rat 10 feet deep in water".

My own experience with the #40111 has been superb. I changed from the "modern" distributor setup to the original points, condenser and lower plate at the time I installed the #40111 epoxy-filled Pertronix coil. And, as suggested by Purdy elsewhere, gapped the sparklers at 0.035 and the points at 0.022. I've driven over 1,000 miles as an experiment with this setup and couldn't be more satisfied with the performance of my coupe.

Thanks for the tip, Purdy!
 
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