spark and no spark

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KitCarlson said:
.
And as others suggest the battery is sick. Any battery reaching about 11V without load is in the danger zone for loss of capacity, due to deep discharge.
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The battery is 12.28V and 10.5 with a load on.

Since I am running long lead off my meter I checked the resistance through the leads to one another. Meter read 0.6 so do I use 0.6 as my base line when doing the test?

If so, then I get this;

Hot Wire
First clamp to starter large stud while other is stab to battery positive, meter reads 1.37 when cranking, so corrected to baseline .77

Ground Wire
First clamp to engine block while the other is stabbing negative post reads .7, so corrected to baseline .1.

Is this ok so far.
 
You don't correct the meter when reading voltage.

Nearly 1.4 when cranking is a LOT. If you are saying voltage at battery when cranking is 10.5, that 1.37 drop through the cable is subtracted from the 10.5 You are already down to 9.13 at the starter, and this does not take in the ground side. I bet you have more drop in the ground as well

What size is the cable from front to rear? I would ALSO remove the connection at the battery and CLEAN the clamps and posts
 
By the way exactly what are you using for an extension wire on your meter? You can look up resistance per foot for wire just google it. A multimeter draws "almost nothing" so measuring voltage, almost ANY copper wire should work fine.

Let's say, example, you are using just one conductor in a scrap of CAT-5 ethernet cable, and that it's 24ga copper Let's say this is 20 ft long. One source shows this at .5 ohms. However, again, the meter draws nearly nothing for current.

you can easily check this by simply making a measurement with and without it. Measure the battery directly with the meter leads. Hook up your extension and re-measure at same points. I bet there is no difference in voltage
 
67Dart273 said:
But you and I both know, "guessing" is not the way to fix this. Logical testing will show up the problem.
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So true, the voltage drops tell most of the story, and knowing the current at the same time is a bonus. Where are the needle meters and carbon piles these days? :)
 
KitCarlson said:
So true, the voltage drops tell most of the story, and knowing the current at the same time is a bonus. Where are the needle meters and carbon piles these days? :)
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Don't know 'bout you but I still have a couple. I have a charging / starter test setup I bought at a garage sale. I forget, it's a big name like mac, and an old autometer pile. The meter on it is junk, but the carbon pile is fine
 
Only used them!, and big resistor banks in lab situations. Always wanted to build one, but that has slipped off my bucket list.

Here is the test sheet that came with the mini-starter from DB Electrical. It puts current in perspective. Up to 500A, imagine that, on a uni-body.

The original quality looked like a fax.
View attachment starter.jpg
 
Found some of loss, and double check what I did yesterday because I forgot about the on/off switch.

Meter reading as follows;

Battery + post to starter bolt=1.2

Battery + post to wire post clamp=.000
Battery + post to top post/clamp of on/off switch=.09
Battery + post to bottom post of on/off switch=.569

bottom post of on/off switch to starter bolt=.601

Also, check the ground again a .611 this time.

Should I get some more cable and run a negative from battery to engine block just to eliminate that question?
 

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Why? What you have proved so far is that MUCH OF YOUR DROP is in the hot cable and the on/ off disconnect.

The neg side.......You need to see if you can narrow it down........It might be "right there" in the K member to frame, or in that "looks like small" ground strap

Check from NEG battery post to "stab" into the trunk metal.

Check from engine block to "stab" into say, the frame rail

ALSO it might be time to "wonder" if your starter is drawing too much current, .........which WILL make drop problems worse. Only way to check that is with a carbon pile / load tester, or try a new starter.

This a mini starter?
 
My 66 Plymouth service manual suggests 0.2V or less on starter cable, and 0.2V or less on ground when cranking. I would think similar for other years. They also say 0.1V drop at solenoid. They even said 0.3V means poor connection or other problems. That is for stock location.

It is a slippery slope, more voltage drop results in more motor current, more current, more voltage drop. I agree with Del, most drop in +, but both are far from desirable.

I am busy with farm work, or I would be making new cables and changing the starter to mini on my 66 Barracuda. I plan to make a study of it, to determine how to minimize drops..
 
It you want to go high tech and $$$$, add a Maxwell Ultracap at starter to ground.
[ame="http://www.maxwell.com/images/documents/datasheet_16v_module.pdf"]http://www.maxwell.com/images/documents/datasheet_16v_module.pdf[/ame]
 
Yes, I have a ebay mini starter

From NEG battery post to "stab" into the trunk metal=.40

From engine block to "stab" into say, the frame rail up front=.09
 
67barracuda said:
Yes, I have a ebay mini starter

From NEG battery post to "stab" into the trunk metal=.40

From engine block to "stab" into say, the frame rail up front=.09
Click to expand...

Then right there in the trunk is part of the problem. .4? Hell that's nearly 1/2 a volt!!! Is that a large gauge cable? Tear into it....REALLY clean the battery terminal, clean/ scrape the trunk bolt connection, make sure it is clean and tight, then re-measure.

That is a LOT of drop in what, 1 ft --1 1/2 ft of cable?

You starting to see what you are doing? Seems like you are making progress
 
Cleaned up and remounted the ground to the frame. Gained 1 volt at starter when cranking, time to work on the positive cable now.
 
You are gainin!!! That is a LOT of "gain" if you just cleaned one connection. Be careful with your connections, it should never have been "that bad."

Tell me about your "hot" cable. Is it commercially made, "home" soldered, ?? And your cutoff switch is junk

Are the cable ends on the hot cables mechanical connections? IE not soldered? That would be suspicious to me
 
Good goin. I would not stop now. Find out why (or recheck!!) the drop in the hot cable. You said it was .6V. That is way too much, and I bet the end connectors are crap.

You can ALSO measure drop "across a connector.

Example........say you want to check the end connector in the trunk for the cable going up front. Of course unless you have a "long" remote starter, this needs two people.

Stab one post right onto the eyelet connector. on the top of the ring end. Stab the other post into the cable proper say, an inch into the cable. There should be almost zero measurable drop
 
67Dart273 said:
I wish some us could get together. I could teach some of you more about voltage drop and troubleshooting in 1/2 hour than I can typing pages on here.
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^^^^^^THIS^^^^^^^^^

Lets have a get together/class Jun 9th 2016. I'll host the beer and the ribs. I have a ton of equipment, good and bad batteries, and old wiring harnesses. Bring a side to share, a chair and a good meter. I'll even let you camp overnite if you promise to take out what you bring in.
 
I don't do ferd trucks nor play with an other man's nutz. Not my thing, but I'll still defend your right's to do as you please.
 
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