Dwell meter reading 86 4.3 motor

MRS

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ok I hooked up meter red to - side of coil and black to neg ground on battery pulled coil wire turned on key and turned motor over by hand. My meter reads 60 to 15 it pegs at 15 witch means points need to be closed more right? they should be at 18 but are at 16 now do I need to ground the coil first to get a right reading or could something else be wrong? New complete tune up parts boat will not run right seems to be lugging bad will not pick up rpm's like it always has. Dwell should be 39..
 
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bruceb58

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You need to run the engine to measure dwell. You can sometimes crank the engine to measure it as well but it will be more difficult. You can't measure it my turning over by hand.

Once you set the dwell, you then need to readjust the timing as dwell affects the timing.
 
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MRS

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Bruce, Thanks I dug out my old dwell meter have not checked dwell in over 35+ years so hard to remember how to use. Will give it a try this weekend boat always ran great was out one weekend and all of a sudden would not ideal or pickup rpm's lugs bad, so trying to start with full tune up and timing almost feels like choke is on but it is not Thanks for the reply...
 

Rinker85

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I'm done with dwell meters, points and condensers. I have decided next spring to purchase an electronic ignition convertor.
 

MRS

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I'm done with dwell meters, points and condensers. I have decided next spring to purchase an electronic ignition convertor.

Rinker, when you do please update what are you putting it in?
 

MRS

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Bruce, what is that? Is it something I should do now?
 

bruceb58

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Points are fine. I would only switch if your distributor bushings are going out.
 

Lou C

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Don't forget if you have a dog clutch Cobra, you can't just bolt in an electronic distributor because it will not work with the ESA system, unless you replace the ESA module with one that will work with it. Otherwise it will not lower the idle speed and you will have trouble shifting to neutral.
I have no issue using points, I find that a set usually lasts at least 5 seasons, they are cheap to replace, and can be found easily in the aftermarket. Remember that point gap and dwell are inversely related. If the dwell is too large, the point gap is too small and vice versa. Dwell is the degrees of rotation that the dist shaft turns with the points closed. Too big of a gap (small dwell) does not allow enough current to build up in the coil. Too small of a gap will cause arcing and premature burning of the points. Simple technology that does the job. I had points in cars back in the old days and only got stuck once because of a bad condenser. I also had cars with the GM HEI system and had a no start because of a bad module once. Yes its nice not to have to deal with them but as Bruce said if the dist is still good I'd stick with them.
 

Maclin

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More details on Dwell measurement....

Dwell can be measured in Percent or Degrees. Some tuneup specs give you both, some only degress. Some dwell meters only read percent, and for those there is a conversion chart on the back usually, or with the instructions. The Percent to Degrees chart will have different "lines" for the number of cylinders as percent is just that and the actual dwell depends on number of cylinders.

When the dwell is right and the timing is set and the distributor is not worn, and the mechanical advance works as designed then the engine will run tip top.
 

MRS

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When the dwell is right and the timing is set and the distributor is not worn, and the mechanical advance works as designed then the engine will run tip top.

That is where I am trying to get if that all checks out will move on to the carb. if still not running right. Thanks for all the replies my friend that helps me is real sick now so I have been with him lately can do on my own but need to get him fixed up first will update when I figure out the problem boat always ran great till this happened Thanks again...
 
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