ballast resistor failure

I need to clarify something. Last night I went down and installed a new set of points. I had to do this because the set that was installed was acting weird. I would gap them set the dwell adjust timing. Run the engine for about 10 minutes life was good. Shut down try to restart and no start. Once I installed the new points and set everything right life was good. Now my question. Why won't I see 9 volts on the - side of the internal resistor coil. The coil is a 3 ohm internal resistor coil. I just want to make sure I'm not over driving the points. I do have an Oscope and could put it on but I'm not sure what I'm suppose to see.

Did you lubricate the distributor cam...what did the actual point contact surfaces look like after the engine would not restart?

The point contacts were a dark almost blueish color. There was also some pitting. My guess was they got hot. I installed a 3 ohm internal resistance coil to get away from the ballast resistor but it looks like I'll have to add a resistor to drop the voltage again.

briang0 said:

Why won't I see 9 volts on the - side of the internal resistor coil. The coil is a 3 ohm internal resistor coil. I just want to make sure I'm not over driving the points.

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You will not overdrive the points. A voltmeter won't show 9 volts, only close to zero (points closed) and 12, points open. The scope will show the real and much more complex story.
My question is what is the wobble amount on the distributor shaft, and did you lube the cam at the rubbing block of the points?

I have sprayed WD40 onto the wiper pad. What type of lube should I use. Can you explain "what is the wobble amount on the distributor shaft". There is np play or side to side movement on the rotor. Also very small amount of rotation. if I try to rotate the rotor.

The last points I bought came with a little vial of grease. Its also available in small tubes, likely 10 lifetimes worth! WD40 won't work..

You put basically a drop of grease on the leading edge on the rubbing block of the points.

I know what you mean I have a different set of points that came with a capsule the size of a Tylenol Capsule with something in it that must be the grease will take care of that tonight. I just don't want to burn up the points I am not good with change. I figure it came with a ballast resistor but I know that technology changes are usually for the better.

Update

Went out for 2 cruises today about 45 minutes each. The engine performed well. I can get 3800 rpms WOT smooth as silk. I had to change my prop last year I ruined my other one. This one was a little diffierent the biggest change is that this one is cupped and the last one was not. I'm running 12 3/4 with a 13 pitch. The guys at the local Prop scan thought that since this one was a 1/4 inch smaller I would not see much of a an rpm change. I was never able to get 3800 rpms out of my other so I'm happy with this.. I do have one question does any one know what the operating temp of the new internal resistance coil I installed should be. I ran the boat harder than I normally do and the after I shut the engine down I grabbed the coil and it was hot not hot enough to burn but I would say about 135 F. I didn't have my temp gun so I could not get an accurate temp. I'll bring it down tomorrow and see what the temp is after we go out again

They do get hot.

Jeff

One thing I have noticed is the engine doesn't start as easy as it one did. Funny thing is before I set it up to all the specs it would start only after the starter turned only a little bit. Now with everything in spec and the internal resistor coil it has to crank for 5 - 10 seconds before it starts. When I had the ballast resistor it started quicker.

You got to remember you have made several changes so to look back and point to only one of them as the 'cause' for a 'change' in operations isn't always wise.

If you want to, you can always hook the wire from the R terminal of the solenoid back to the + side of the coil. It will no longer bypass the ballast but will eliminate any voltage drop that exists in the harness going to and from the ignition switch.