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coil need to be grounded?


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Seems like a stupid question, bit puzzled here.

spark was fine and motor ran.

I pulled the distributor and generator, oil fill tube to pull the welsh plugs and flush the block.

 

When I put it back together, I left the coil bracket off, doing some work to it and have new wires ordered ... just want to start the motor and idle in driveway to check coolant problem.

Problem is, I have juice to the coil with the key on, but no juice on the other post going to the distributor.

The only thing different is the metal coil is not mounted to the metal coil bracket ,  just sitting loosely on the frame and probably some dirt as a insulator. thus my question, does the body of coil need to be grounded?

 

I am thinking it does not, but then this is a brand new coil and hate to think it went bad already. I know some coils require a resistor, not sure how would know if this one does or not.

And I have not seen a ballast resistor on these old trucks  .... kinda at a loss here, will fix the coil bracket and then get the coil mounted, kinda thinking this is not the problem and looking for ideas.

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well..considering the fact that it worked before pulling why you questioning the components...I would suggest you carefully go back over your connections...especially the one on the distributor end to ensure it is connected properly..if voltage at the coil and yet no spark..I would think the connection is poor and not allowing the points to take the coil primary to ground.....(ie...open)

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The coil does not need to be grounded. The primary windings in the coil gets its ground through the distributor when the points are closed. When the points open, the magnetic field that is created by the primary windings collapses causing the secondary windings to generate a high voltage current. 

 

A ballast resistor (some vehicles use a resistor wire) is used in some vehicles to lower the voltage to the primary side of the coil after the engine starts. Typically, the full battery voltage is used during cranking, then a lower voltage is used once the engine is running. The lower voltage helps to keep the coil cooler and reduces the likelihood of burning the rest of the ignition components. 

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now is the time to come clean.....lol......are you still 6 volts or are you 12 volts....inquiring minds need to know.....your coil will need to be internal resistor if you not using an external resistor IF 12 VOLTS   if 6, just ensure you not running a internal for this application...and no external either...again...I fyou have voltage at the coil primary and do not lose that voltage when the points close..you have an open between the coil and the points...….

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It is 6 volt still. 

I also took the carburetor apart and cleaned it, when I tried to start, it was not firing, I shot some either in it and no change, so looked at spark.

Thats when I saw  I had juice coming into the coil but nothing coming out.

I scratched my head and walked away to think about it, leaving the key on, a few min later returned and turned off the key, coil was very hot and uncomfortable to touch.

I do not think the coil would be that hot under normal conditions, unless motor was running and hot also.

 

 

20 minutes ago, Jomani said:

The coil does not need to be grounded. The primary windings in the coil gets its ground through the distributor when the points are closed.

Possible that the points were open when I used my test light? Then would be no ground ?

Reading that you would get a flashing light as the motor spins, points open and close?

I have the old coil here, I can hook it up and see if get same thing.

 

I have to be honest, I ran into this yesterday afternoon. The weather was so nice after a week of rain, I went out and mowed the grass and never got back to this problem to look more.

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sounds like its shorting at the distributor. There is a bakelite sleeve that insulates the small wire that passes thru the Dist. After 70 years it breaks when you look at it.  I would check continuity between the coil wire and the dist case, and would guess you have  a short. I fixed mine with the body of a bic pen, using the clear plastic as the insulating tube.

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Pull the primary wire that goes to the dist, off the coil, and recheck for voltage coming out of the coil.  If you do, the problem is after the coil, meaning at, or in the distributor.

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if he had not fire when spinning..and voltage on the input to the coil..he had to have checked that with the points open....as for walking away after messing with it with key on and finding the coil very hot....the points have to be taking it to ground when closing...as for the reason to no spark, did you check the output coil wire to the distributor for possible damage when pulling the distributor from the vehicle....as it was running prior, it is a simple oversight...you got to retrace your steps....if you don't know what is wrong, prove what is right....you will find the cause...

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I ordered a carb rebuild kit and the other day I completely disassembled the carb and ended up just cleaning and oiling it .... It had a lot of sediment on the bowl, and the jets were gummy from old gas, I cleaned everything up and made sure the check balls were free and moving, oiled the accelerator pump and I put it back together.

 

Looking inside the throat I see fuel sitting in the bottom, that should not be.

Pulled a plug and it is wet

Probably the inlet not shutting off

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22 minutes ago, Plymouthy Adams said:

odds are  you disturbed these sediments when doing the work.....

By sediment, I meant was a layer of mud on the bottom of the float bowl ... sure it was not actual mud, but was brown and wiped up like mud.

Float level seems fine ... there is fuel in the intake, but may be from me priming the engine a few times with a can of gas.

 

The accelerator pump is not working. It felt stiff when I assembled it, kinda figured it would work itself out.

Had good leather on it, I put some light 3 in 1 oil on it .... maybe to much and it just to fat to slide up and down in the bore.

It just sits in one spot and the gas pedal moves the spring up and down. Need to fix this for sure. I do have the new accelerator pump in the kit to install.

 

I suspect with the accelerator pump stuck, it was allowing fuel to pour through the carb while turning the engine over, why a inch of fuel sitting in the intake manifold maybe???

Old cars are fun  ?

 

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8 minutes ago, Plymouthy Adams said:

take the pump plunger out and soak it over night in some light oil...lose the 3 'n 1  oil,  you'd do better with Crisco than that stuff

Hrmmm, on the shelf I have 10/40 engine  oil, wd-40, pb-blaster,  ATF,  I have some clear air tool oil for my nail guns, lubricates the rubber o-rings and provided by the tool manufacturer, I have some honing oil to sharpen knifes with ???? .... Tomorrow when the stores are open can go to town and buy some specific oil, nothing open here on Sunday.

What oil would you suggest?   I really think this stuck accelerator pump is the issue, and with no advise I would most likely use the 3 in one oil on new accelerator pump also.

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Just went thru this with a brand new carb kit where the accel. pump did not do anything after 5-6 days of soaking in med. weight oil.  ?

 

Finally got PO'ed and got out a flat blade cheap watch maker/glasses repair and carefully got it under the lip of the seal and gently pulled outward on it . Finally after several tries I was able to get all the way behind the lip and work my way around it. Made several passes slowly pulling further outward.

Re soaked the accel. piston again overnight and it finally worked as needed!

 

Time to put the old carb back together again and on the car to run!

 

DJ

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I had the same problem w an accel pump I just did, and I used the same method to "convince" the plunger it was time to get into shape..   After getting the plunger to actually push fuel, I found that the jet at the top of the carb was badly plugged.  In order to access it you need to remover the round steel plug at the top of the carb opening.  A fine banjo string was needed to get it opened.  Never saw one plugged as badly as this one was.

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7 hours ago, MBFowler said:

I found that the jet at the top of the carb was badly plugged.

I found that mine was really gummed up, not completely plugged but could feel the resistance pushing the wire through the first time.

 

I ended up putting the new accelerator pump in it, the old one is swelled up to much, needs to dry out and then maybe it will work again. I put it in the kit and mess with it later if needed.

 

Big issue now is getting it dried out, letting it sit a few hours with no plugs and dried the plugs with mapp gas torch.

Off to pick up some starting fluid and see if it helps.

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