Logo
FULL SITE MENU

Location of balast resistor

D

diveryates

New member
"I have a '83 C.C. Catalin

"I have a '83 C.C. Catalina 280. Engine:single '83 Mercruiser 230 (305 cid)
inboard.
1) Can anyone tell me where the ballast resister is located and how to recognize it?
2) What is its function?

My best guess for the Ballast resistor location is on the port side of the engine, bolted to the front portion of the port exhaust manafold. There is a somesort of electrical assemby and a square plastic cover under which is a resetable breaker. That is all I can see without disassembly. Is Ballast resistor is there or somewhere else?

Great web site- always the best info, Thank you"
 
Are you even suppossed to have

Are you even suppossed to have one?. Many coils have internal ballast resistance built in and do not need external ballast resistance. In that case you would not have one.
 
"Hey Roy
In most cases the ba

"Hey Roy
In most cases the ballast resistor will be mounted fairly close to the ignition coil, "if there is one fitted".
The resistor is used to reduce the voltage down at the positive side of the coil to the correct voltage for the coil to operate properly.
(thats a fairly simplistic description of what it does)
If you find the positive terminal on your coil and trace back the wiring harness you should find your resistor, it will look something like a small ceramic box with a couple of terminals on it.
I did say above if you have one as there are different ignition systems with different coils and not all use an external resistor, some systems will also use a wire of the specified resistance which has been built into the wiring harness and so it wont be visable.
Have a look at your coil and see if it has any markings that say "use with external resistor". Take a voltage reading at the positive terminal on the coil with the ignition "ON" and note what the voltage is, if it is 12 volts or better you do not have an external resistor fitted to your ignition.
Hope that helps
Cheers
Peter C"
 
"Just for the record, if you b

"Just for the record, if you buy a 'normal' 12 volt coil you can eliminate the ballast resistor and its tendency to screw up on you. And if you get a high performance 12 volt coil, it will have even better spark.

Jeff"
 
"Thanks guys

OOPS! Further

"Thanks guys

OOPS! Further info:
I have the thunderbolt electronic ignition. Does that eliminate the Ballast resistor or not?Sorry 'bout that!

Not withstanding the above, I understand:

1) Some coils have a internal resistor. Some will say: 'use external resistor'.
If I disconnect and Read voltage at Positive terminal- if I read 12+ volts =there's no ballast resistor on that wire. If < than 12vdc on that wire=there is a resistor. If the resistor is internal to the coil, I disconnect all leads on one side and read resistance across the +/- terminals. If the resistor is present, around 1-4 ohms? If no resistor < 1 ohm?

2)There are two types of external resistor: a small, ceramiic, box-like component with two wires/terminals coming out of it or a 'resistor wire' which is hard to find as it's part of the harness.

If the resistor is a wire type, wouldn't there be some sort of difference in color or a marking in case it fails? If it is this type and it is not marked, the only way to confirm there is a resistor would be to disconnect one end and read across the wire to see if a resistance greater than 1 ohm exists. Is this correct?

Again, this all said, does the Thunderbolt Electronic Ingnition eliminate the ballast resister?}"
 
"I dont think that you have on

"I dont think that you have one in that year. 1982 and under with points have one, never seen it but it is in the engine harness, between the plug in and the coil. Must be a wire style, not a ceramic. I have had to bypass these on some after installing electronic conversion kits. They wont start till you let off the key while cranking over."
 
Back
Top