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Old 12-04-2017, 04:08 PM   #21
FlatheadTed
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Default Re: Starting problem

If you do what GM says you should get a reaction ,or to put it another way ,hook the jumper cables to the battery any way around ,hook the other end of one (any one ) to the terminal stud on the starter ,the other one ground it to a head stud or the case of the starter, you will get a few sparks but that should turn the starter .you could also create a ground with jump cable to the case and + then join the solenoid cables again
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Old 12-04-2017, 05:12 PM   #22
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Default Re: Starting problem

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Originally Posted by 1stford View Post
So the ground at the starter could be an issue? Starter has recently been painted and the spot it is bolted to has been painted. Starter engages it’s a matter of starter only getting 2.50 volts. Starter was checked yesterday and works fine.

Whats the correct engine to frame ground strap.
You have confirmed the condition that others have told you is the problem, so why continue to question it?
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Old 12-05-2017, 04:37 PM   #23
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Default Re: Starting problem

Starters draw a lot of current, and will reduce the apparent voltage when under load. Have the amperage to the starter when activated checked. The reading will be somewhere in the 200 amp range. If too high or low, the starter is probably in need of repair or replacement. The voltage drop starves the coil, making for hard starting. We use an Amprobe to measure current, as most multimeters can't handle the load.
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Old 12-06-2017, 01:33 PM   #24
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Default Re: Starting problem

Literally just had this happen on our '42. Jammed starter Bendix and it took a bit of effort to free it. Key was rocking until I could see the engine pulleys move a little.
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Old 12-06-2017, 09:00 PM   #25
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Default Re: Starting problem

Your making me think hard. Its been awhile since I took an electrical class. I'll give this a shot. This will be a long-winded explanation only because I want you to understand what is happening. I think your onto the problem you just don't know what and why its happening?

Lets start off with your battery reading of 6.55 volts. This is the available pressure (voltage) in the system to push the electrons through the circuit. But this might only be a surface charge. That is where there is enough voltage available to give you a good reading on the meter but not enough to power a starter. The second you put a load on it that voltage will drop from 6.55 volts to zero if the battery is bad or discharged. I don't think that is your problem but I'll cover it anyway. The first thing we do is a load test. You probably don't have the proper equipment to put a large amperage draw on the battery to test its capacity so the next best thing is to turn on the headlights and see if they stay lit when you try to crank the engine. If they do chances are the battery is good. That is the very first thing you do if your stuck somewhere with a no crank situation. A better test for the battery would be to test the voltage when the engine is trying to crank and see if there is enough available voltage. If the battery is bad the voltage will drop off to practically nothing as soon as you try to crank it. On a 12V system you would crank the engine for 15-seconds then let the starter cool down for 15-seconds and then crank it again for 15-seconds. During the second cranking test the voltage should not drop below 9.6 volts. Even with that reading I wouldn't keep that battery very long, its on its way out. So you get a few months more out of it and then stuck no where. If a battery is four year's old I'm getting rid of it. I'm sorry but I don't know what the cranking specs are a 6V system. Another note, you never want to crank a starter for more than 15-seconds. The windings will get so hot the solder will melt. 15-seconds cranking and 15-seconds resting, that is the golden rule.

You had 6.55 volts between the battery terminal on the solenoid and ground. That's because you are checking the available voltage of the battery. Your just checking the voltage at the other end of the battery cable which is directly hooked to the battery's terminal. As long as the circuit is not energized you are doing the same thing as checking the voltage across the terminals of the battery.
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Things get a little confusing when you start check a circuit when it is turned off and then again while it is turned on. All the readings change. That is because of voltage drops and how the voltmeter works. Your meter has resistance built into it so that all of the amperage in the battery does not try to flow through the meter when you hook up the leads. If the meter had zero resistance it would go up in smoke just like a wire hooked directly between the two battery terminals. I had a neat college professor that worked for Howard Hughes as an electrical engineer. His favorite saying was, "all electrical devices run on smoke because when you let the smoke out they don't run anymore." Been there done that in my youth.

Voltage is electrical pressure. It is the force that pushes the electrons through the circuit. Think of your starter circuit as being powered by 6.55 lbs. of water pressure. If we wanted to test for a blockage in the circuit we would need to tap into the system at different places along the way and take pressure readings. When the pressure dropped we would know we were taking readings past the spot where the blockage was. We use the same concept with a voltmeter only we get our pressure readings differently. The way we check for voltage pressure and restrictions (resistance) is to touch the positive and negatives leads of the meter to different places in the circuit while the circuit is energized. Remember we cannot check for pressure if it is not flowing in the circuit. You will not hurt anything, you will not let the smoke out of the meter as long as you remember two things. While on the ohms' resistance scale you cannot test for voltage this will blow the fuse in the meter. If your going to use Ohms scale disconnect the battery first. You cannot put your meter directly into the circuit (amperage scale) unless your testing really small circuits. That's where the amperage only has one path and that is through your meter to get where its going. You will let the smoke out of your meter. I don't think you would ever use the amperage scale on an old car. If your plugged into the DC voltage scale you won't hurt anything on an “old” car or the meter by probing around.

Going back to our water analogy, were not going to drill a hole in the circuit to test for pressure because the voltage flows on the outside of the wires where we can easily get to it. This is going to be even easier to test. The voltmeters leads are connected the same way a bypass pipe is connect around a restriction in a main water pipe. Basically you are just touching the leads to the two closest spots you can connect to while moving the connections down the circuit to the next two spots you can get to. Example; battery post to battery cable terminal, battery cable terminal to the other end of that battery cable, battery terminal on the starter solenoid to starter terminal on the solenoid and just keep on going until you go completely around and end back at the ground post on the battery.

So what are we doing. If this was the water pipe with 6 lbs. of pressure and no restriction between the two spots our bypass pipe was connected to no water would flow through the bypass pipe because it is so small that it has more resistance than the main pipe does. Now lets put a restriction in the main pipe that blocks about 1/3rd of it. Lets put it right between where we have our two bypass pipe connections. 2/3rds of the pressure will flow through the main pipe but the remining other 1/3rd will try to flow around the restriction and through the bypass pipe, it has no where else it can go. This is exactly what the voltmeter is reading, the amount of voltage (pressure) that cannot get past the blockage (resistance) so the voltage tries to take the bypass route through the meter to get around blockage.

In your case there is 2.45 lbs. of electrical pressure (voltage) registering on the meter. There should be 6.55 volts between the starter terminal on the solenoid and ground. Let me explain why. When you try to crank your engine 6.55 volts of pressure is pushing the electrons through the circuit. Every time that voltage runs into some resistance the resistance will use up some of that voltage pressure. The more the resistance is the more voltage pressure loss there will be at that spot. The very last resistance in the circuit will use all the remaining voltage. Wires, switches and connections (if they are good) have zero resistance. So if we were to put the volt meter on each end of a good battery cable and crank the engine that cable should have a zero voltage reading. All the available voltage can go through that cable. If there were resistance in the cable some of the voltage pressure would register on our meter showing a voltage drop. Now we get to the starter solenoid. There should be very little resistance through the contacts in the solenoid, maybe .2 of a volt. There is no resistance built into those contacts so no voltage or very little is used up. Now were on to the starter cable. Again, no resistance built into it, no voltage drop. Now to the starter, it has all kinds of resistance built into it, miles of small wire windings. That is where our major voltage drop should be, pretty close to the battery voltage. If you were to put one voltmeter lead on the starter terminal and one on the starter case and crank the engine there should be close to a 6.55 volt drop across that starter. If there is not we have unwanted resistance somewhere else in the circuit.

All the available voltage at the battery needs to be accounted for in a circuit So If there were a .1 volt drop on a cable, .2 volt drop cross the solenoid and a 3 volt drop across the starter they had better all add up to 6.55 volts. If they don't we have more resistance somewhere we need to find. In this case we are missing 3.25 volts. that is a huge drop and we have a whole bunch of resistance we don't want somewhere in our circuit. That starter is not going to crank on 3 volts. It cannot build up a big enough magnetic field to rotate the armature.

When you touched the lead to the starter solenoid on the starter terminal side and the other lead to ground then cranked the engine you should have had a 6.55 volt drop on your meter across those starter windings. You had 2.45 volts. Guess what, you have a whole bunch of unwanted resistance somewhere else in the circuit that is eating up your voltage. Its not between the starter terminal on the solenoid and the ground connection at the battery because you just checked that part of the circuit. It has to be in the starter solenoid contacts or the cable between the battery and the solenoid. Stick the leads on both sides of the solenoid and crank the engine and see if your missing voltage shows up there. The contacts could be pitted or the windings may be too week to pull the contacts tight against each other. If its the old style with the button on the bottom you can push it in and eliminate the starter button , wiring to the solenoid and solenoid windings. Then check for a voltage drop between the battery post and the battery terminal on the solenoid. Your missing voltage should be in one of those two places.


I had a friend that worked in a dealership. A brand new car was having intermittent cranking problems. It was on its third visit to the dealer for the same problem. If they did not fix it this time they would need to buy the vehicle back under the California Lemon Law. They tried everything replacing. What they finally found was when the battery cable was made the factory did not strip off the insulation when they crimped the lead battery post terminal end on. Sometimes it made contact and sometimes it did not. You would have looked at that new cable and thought there no way anything could be wrong with it. It has to be the starter or the solenoid or a loose connection. This would drive you nuts, plus your not getting paid on top of it. But had you started at the battery and moved along the circuit doing voltage drop tests you would have found the problem at the very first place you checked. A voltage drop test across that cable is what found the problem.

Which brings up a point. If you were to hook up an ohm meter and check for resistance on that new cable why would it have not shown the cable was bad? That is because your putting such a small amount of amperage through the cable from the voltmeter's internal battery it has no problem flowing through where the cable is making that little bit of a connection, it would read zero ohms of resistance and appear to be I perfect condition. But when you try and force 300 amps of starter current through that tiny connection it can't handle it. It won't fry that spot in the cable because there is some resistance. This is why we do a voltage drop test on high amperage circuits to find resistance. But it will work good on any circuit. Its very useful for checking bad grounds on lighting circuits.


Here is a link to a YouTube video on performing a Voltage drop test. It will make more since when you see the test being performed. It will make more since when you see it being done. I just wanted you to understand why it works. You master voltage drops and you will be able to fix 90% of the electrical problems on your old Fords

If your really interested in learning more go on YouTube and search voltage drop testing starter. There are lots of good videos on this.
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Old 12-07-2017, 01:57 PM   #26
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I was reading back through the posts and saw where you had bypassed the solenoid. So that eliminates it so forget about what I said in the last post. I though about this some more. If you found a 2.45 volt reading between the solenoid's starter terminal while using the frame as the ground for your voltmeter the voltage drop could be in the positive ground cable from the battery to the frame. So if you hook a jumper cable from the battery's positive ground post to the starter's housing this would bypass any resistance on the ground side of the circuit.

If the jumper cable fixes the problem, before you remove any of those cables and disturb the connections use your voltmeter and perform a voltage drop test so you can verify exactly where the resistance is? Is it in the cable or in the connections? Your missing 4.1 voltage drop will be there. Its a fun test little test and you'll learn something. Let us know what you find

Last edited by Flathead Fever; 12-07-2017 at 02:26 PM.
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Old 02-11-2018, 11:24 PM   #27
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Default Re: Starting problem

Thanks for all the responses. I’ve not been in the shop for a while but I’m going to take the info you guys have suggested and get Er done. will report back. Thanks.
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Old 02-15-2018, 08:23 PM   #28
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Thank you for the feedback. I was able to correct my starter issue with the advice given to rework some grounds, much appreciated.
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Old 02-16-2018, 10:52 AM   #29
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Default Re: Starting problem

X10 need good grounds. Check all lines for corrosion & all terminations for clean grounding points. After clean use a bit of electrical grease to keep from corroding. As JSeery indicated your starter gear could be jammed against the flywheel gear. Check for starter motor alignment which can cause.
Good luck
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Old 02-16-2018, 11:39 AM   #30
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Default Re: Starting problem

Sounds like a problem I had a couple months ago with our '42. Ran all the electrical tests, but it was a stuck starter. Watch the pulleys while a couple friends help rock the car in 3rd gear. When they finally start to move, and it took some effort with our car, it should start.
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Old 02-16-2018, 01:37 PM   #31
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Default Re: Starting problem

Ditto on checking your grounds. I blew up a battery once, trying to overcome a bad ground on a fresh rebuild, also with fresh paint at the ground surfaces. That battery went off like a shotgun, blowing acid and plastic case shrapnel all over the place! Glad I wasn't leaning over the battery when it blew!
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