voltage across primary of ignition coil

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1969dodgedartgt

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hey guys

I'm in the middle of my first tune up ever and am following this procedure
http://www.secondchancegarage.com/public/670.cfm

I replaced the condenser, plugs, points and dist. cap.
all was well until I tried to start the thing for checking dwell time, she wont start.

I checked for spark at plug nothing, I check for spark coming out of secondary coil cable, nothing.
NO SPARK :(

i checked voltage across primary of coil when cranked, reading about 7 volts. seems I have high resistance there somewhere.
car was starting before tune up.

Time for me to look at wiring a bit more and maybe try and pinpoint where the resistance is. sound right?

advice is more than welcomed :)
I'm reading 12.4 across battery, voltage regulator and alternator are pretty new but I need to look more at wiring to know if they play into the circuit at this point.

thanks all

and a pic for you,
 

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As quickly as you can, get the three books described in this thread. Your primary wiring (to the coil + and -) looks like it might be a little chewed up; I'm looking at the coil end of the wire painted orange in your photo. Check all those connections carefully. Remember, line voltage drops while cranking because of the starter's load on the battery. Even with "just" 7 volts across the coil, if everything else is working correctly you'll have a spark. Remember that when the engine is running, the coil only sees about 7 volts because of the ballast resistor. I think it's probable your points are not opening because they're not adjusted correctly. Have you popped the cap off and verified that the points actually open and close? Another quick check: remove the distributor cap. Make sure the points are closed. Turn the ignition key to "on". Remove the coil cable from the centre tower of the distributor cap and hold it so its metal end is about ¼" away from the coil hold-down bolt or another good ground. Use a nonconductive rod such as a chopstick or popsicle stick to pry the points apart. You should get a spark from the coil cable to ground every time you do so. If that happens, then either the points aren't opening properly as the distributor spins (adjust them so that they do) or the timing is so far off that the sparks aren't reaching the right cylinders.
 
thanks Dan, I do need to get some more books and do reading

points do open and close, just checked. I carefully gaped them

after doing your second test and seeing some sparking in the distributer it eventually started sparking from the secondary of the coil... and then I tried again and I got some boom in the engine :) :) :)

I think I know what the prob was, the connection coming out of the secondary of the coil looks green like the statue of liberty, I pushed that cable in real well and got the spark.
thanks soooo much dan, I wasnt sure about the voltage across the primary (will read more, get books)

heres a pic of the old wire that was connected to the coil, look at that green. say ewwwww

also the secondary wire on the coil seems to fall off easily, I think I'll get a new coil ASAP

thanks again :cheers:
 

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Glad it worked out, I feel for you, Just got done rewiring mine and know all about wiring headaches
 
man, dwell angle is reading about 140 when it should be about 30. its REAL rough and getting some back fire out the carb...

can I possibly fix that dwell by changing the gap? (I guess I must be able....

I'm thinking at this point to use my AAA to tow to mechanic and have them finish it proper, as I watch. it was a valiant effort, I have more to learn


ordering those books, great prices, already have service manual
 
Yup, dwell is directly influenced by point gap. Sounds like your point gap is way too small, which will definitely cause rough running.
 
yah, i'll fiddle with it latter....

hey I noticed that the outer part of the points hits the hold down screw and sparks when the points open. I kinda think that this should not happen but am not sure. This maybe is causing dewll to look like its way off? I might just throw the old points back in to see if this happend with them.

might grind that screw's head down a bit.
 
There should be plenty of room for that screw next to the points arm. I'm wondering if you got the right points, or ---the points normally have a locating pin which they "snap down" onto, (been awhile since I was into a /6) maybe they are "dislocated."

Can you post a nice clear pix of the points as installed?

Also, is there a possibility that your dwell meter is out of calibration, or that you had the switch (4-6-8 cylinder) in the wrong spot.
 
1969dodgedartgt said:
yah, i'll fiddle with it latter....

hey I noticed that the outer part of the points hits the hold down screw and sparks when the points open.
Click to expand...

That's a problem. Sounds like the points may not be fully seated on the breaker plate, or perhaps they are not quite the right points, or they are of poor quality. Brand and part number?
 
dwell meter might be miscalibrated its new to me, directions didnt mention any cylinder setting, I'll double check
its a innova 5568 Timing Light with dwell meter

btw its a 318 8 cylinder engine, i'll take pic tomorrow

the points are MasterPro has 2-1013 on box and BWD ref: A110v

I also have a BWD select A110v but I could not get those to seat on the locating pin, pin was just a bit too big. I think the BWD's might just have been a bad batch or something. I might go ask for a different set of the BWD's. or i could file the hole a bit bigger on the points if need be.

the MasterPro's when down on the plate well. BWD's not at all.


That contact might only been occurring when I manually pull the points apart as prescribed by the mentioned test, I'll take a closer look tomorrow.
 
1969dodgedartgt said:
dwell meter might be miscalibrated its new to me, directions didnt mention any cylinder setting, I'll double check
its a innova 5568 Timing Light with dwell meter

btw its a 318 8 cylinder engine, i'll take pic tomorrow

the points are MasterPro has 2-1013 on box and BWD ref: A110v

I also have a BWD select A110v but I could not get those to seat on the locating pin, pin was just a bit too big. I think the BWD's might just have been a bad batch or something. I might go ask for a different set of the BWD's. or i could file the hole a bit bigger on the points if need be.

the MasterPro's when down on the plate well. BWD's not at all.




That contact might only been occurring when I manually pull the points apart as prescribed by the mentioned test, I'll take a closer look tomorrow.
thanks again
Click to expand...

I actually went to the Equus website, a horrid experience, and downloaded the manual for your light. That thing SHOULD be a pretty spiffy deal. Directions for dwell are on page 8, and you certainly do have to set it. I don't know how I figured you had a /6

http://www.equus.com/Content/Support/Manual/5568e.pdf

Also I went to BWD

http://www.bwdbrand.com/Online Catalogs-eCatalog/Content.aspx

Evidently BW is now part of Standard Motor Products? I don't recognize Master Pro, where did they come from?

and if you have a factory Mopar aluminum, single point dist, the A110V no. shows as correct. You should not have to file, or modify them. I would pull them back out, and examine the breaker plate for dirt, grime, or damage. They should set right down on the locating pin, and before you install the screw, you should be able to "rotate" them in/ out away and inwards towards the rubbing block. Incidently, put a TINY dab of lube (points used to come with it) on the rubbing block on the APPROACH side, that is, visualize the shaft coming around CW to the rubbing block. I always wipe down the dist. cam to get rid of dried grease and dirt.

If you get this figured out, try to set them a "little wide" that is, dwell of about 28*, and recheck in about 500 miles--they'll wear a little closed, and you'll have to recheck the timing, which retards as the points wear closed.
 
I think Master-pro is O'reilly's budget line parts.They are probably sold by someone else also. I am not sure if I would use some of the parts from master pro. TRy to get some better ones that fit better. Their plugs wires are good for a year or so. The caps really dont look good at all. But I know how it is when you gotta get things done and you are trying to stretch the dollars..
 
yes that had an 8 cylinder setting, dwell is now showing 35 ish. just about where they should be, i'll open them up a bit. still rough as heck, I double checked the plug wires for firing order, looks good. I'll open them up and try to set timing....

hope things go well.... :0

the master-pro is from O'reilly, all the parts i got for this tune up are from there...
 
1969dodgedartgt said:
the points are MasterPro has 2-1013 on box and BWD ref: A110v
Click to expand...

Off-brand junk.

Mess around with points to get the engine running if you have to, but seriously, points are not worth spending money or time on. Upgrade to electronic ignition at your soonest opportunity. It's all benefit, no drawback. I like the HEI upgrade myself, but there are other good ways of having electronic ignition, too, including some (Petronix) that don't require a new distributor.
 
those points are hitting the hold down screw, gona take them back try and get a diff set of the BWD's

and do a better job of cleaning the inside of dist.

pics....
 

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slantsixdan said:
Off-brand junk.

Mess around with points to get the engine running if you have to, but seriously, points are not worth spending money or time on. Upgrade to electronic ignition at your soonest opportunity. It's all benefit, no drawback. I like the HEI upgrade myself, but there are other good ways of having electronic ignition, too, including some (Petronix) that don't require a new distributor.
Click to expand...


I kinda wana leave it points based... you almost had me going HEI with some reading I was doing...
 
ok i modified that screw and it doesnt spark on the screw any more....

but now I'm not getting any boom,
I see spark at the plug, and on cranking I get a horrible struggle. maybe my timing like 180 off or something? If I disable the distributor it turns over ok with every thing connected it seems to be fighting with itself...

time to step away for a bit....
 
yeah, my original points looked like that as did the BWD's

i checked the plug wires, i'll triple check,
gonna try advancing and retarding timing too


was timing, she breaths again
 
1969dodgedartgt said:
yah, i'll fiddle with it latter....

hey I noticed that the outer part of the points hits the hold down screw and sparks when the points open. I kinda think that this should not happen but am not sure. This maybe is causing dewll to look like its way off? I might just throw the old points back in to see if this happend with them.

might grind that screw's head down a bit.
Click to expand...

Wrong parts.
 
1969dodgedartgt said:
I kinda wana leave it points based
Click to expand...

Oh! You prefer the harder starting, the poorer driveability, the poorer fuel economy, the unstable timing, the constant need for maintenance, and the difficulty and expense of buying quality points and condensers, eh? :toothy10:
 
slantsixdan said:
Oh! You prefer the harder starting, the poorer driveability, the poorer fuel economy, the unstable timing, the constant need for maintenance, and the difficulty and expense of buying quality points and condensers, eh? :toothy10:
Click to expand...


all that fun and more :)

I may eventually go mopar prof electric as I was inches away from doing before

for now I just did my first tune up with the pain in the *#( points and it runs very very nice, those points in there are crap and do need to go. I could not adjust the dwell time above 26, hopefully things will wear to get a higher dwell

thanks again for all your guys help,
maybe I'll post a video soon

WE DID IT :) :) :) :cheers::cheers::cheers:
 
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