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Old 01-25-2019, 06:22 PM   #21
flatjack9
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Default Re: engine won't turn over

A lot of answers, but it boils down that you either have a starter problem or a connection problem. All grounds must be totally clean, no paint or anything to insulate. When the engine warms up things can expand a create a bad connection. Also the starter can be affected by the heat of the engine. Don't over think things. Do you have good grounds from the battery to chassis and to the engine?
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Old 01-25-2019, 08:04 PM   #22
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Default Re: engine won't turn over

Have u checked the ground to engine to chassis grounds . If u haven’t disassembled them & abrasive cleaned the connections u should. Use some electric conductive grease when reassembling to insure longevity.
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Old 01-26-2019, 12:41 AM   #23
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Default Re: engine won't turn over

poor mans starter test. clamp it in a vise, hook up the neg to a battery, touch another cable to the case...it should jump up to full rpm immediately, if its slow, its bad. if it jumps look for another bad connection. in this case, since it seems to react to heat, i would run the starter enough to make heat. feel it...get it warm...run for a minute or so then pause...get the case warm and see if it changes the rpm climb. its free, its easy
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Old 01-26-2019, 01:38 AM   #24
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Default Re: engine won't turn over

The starter mounting face to pan must be bright metal to metal, no paint here, as this surface provides the electric ground to the starter.
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Old 01-26-2019, 05:08 AM   #25
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Default Re: engine won't turn over

Most overlooked is clean end plates on the starter and clean starter housing ends. End plates are aluminum that doesn't get along with steel too well especially the end that
holds the brushes plus dirty corroded thru bolts worn shaft bushings. And then with a new engine parts have to get use to each other they will tend to run a little hot. They will need
miles to straighten out. Running a fresh engine time to time or on a test stand just won't
cut it, it has to be loaded and unloaded over and over (has to be 'run in" under load)
Just think a person buys a brand new lawnmower gas her up pedal to the metal all day:
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Old 01-26-2019, 08:26 AM   #26
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Oh just thought about this to make ya feel better. I bought a brand new 1970 Coupe
Deville all my colors perfect. So I go to work 20 highway miles, get off maybe get
gas. Pay the guy and rah ---rah. sit there blocking the pumps. 1/2 hr finally starts.
brought this thing back to dealer they say all is good. The fix, it has maybe 600 miles on it, and I drove directly to Lincoln Mercury dealer One new black Continental End of problem....So this condition does happen but not so on a new big buck vehicle. I look back and call that "Kid" power (course I had good job) and new bones.......sam
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Old 01-26-2019, 11:18 AM   #27
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I rebuilt the engine in my 4 cylinder Ford Courier years ago, cleaning and painting everything. When I tried to re-fire the engine, I couldn't get the starter to spin it freely. Thinking it was just tight with new bearings and seals, new bore, pistons and rings, etc. I connected a high-current battery charger to the battery and tried it. The battery exploded blowing the plastic top and battery acid everywhere, luckily I wasn't standing directly over the battery.

Well, after I cleaned up the mess and got the battery acid off of me, I started checking connections. As it turned out, the problem arose from a poor ground at the engine block from all of that pretty engine enamel. I'm guessing that a spark from connecting the charger set off that little Hydrogen Bomb! I'm talking about a blast that sounded like a shotgun blast almost in my face. I considered myself lucky, with no injuries.

I was a lot younger then, as well. Ha ha

Al Hook
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Old 01-26-2019, 02:08 PM   #28
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Default Re: engine won't turn over

I've repeated this several times on this forum about learning how to check for "voltage drops" with a volt meter. Nobody has ever comeback and said they tried this test and they found the problem. If the problem is excessive resistance, bad connection, switch , cables this test will locate the problem every single time and pretty fast. This is the number one test you need to know when diagnosing electrical problems on old cars. Its really easy to do but for some reason nobody will try it? These old cars have resistance all over the place in their circuits. A voltage drop test will tell you exactly where that resistance is.

More heat causes more resistance. Most likely its your starter getting hot and causing excessive resistance in it. You don't want to guess at the problem, go buy a starter and then be wrong. What if you just need new brushes in the starter? What if it just a bad spot in the starter cable connection? This could be a $10.00 fix. You need to have a volt meter to diagnose this stuff. Its one of the most important tools that you should have in your garage. I just used my meter yesterday to verify the armature in my Kubota tractor's ($300.00 alternator) had a open in it before I went down ordered a new starter. You can't guess at this stuff, you need a meter.

I cannot stress how important it is for you to understand how electricity works. What is the difference between amps, voltage and resistance and how they effect each other. Its all so easy to understand if your interested.

This all you need to know about electricity to get through 90% of repairs, this and a volt meter. It all works like the water system to your house. The battery is the water tank up on the hill. The alternator is the pump that fills up that tank. The wires are like the pipes that carry the water except the wires carry electricity. Water flows and turns a water wheel for grinding wheat. Then the water flows back into the ground and the pump sends it back up to the tank. When your electricity passes through the last operating component in that circuit it does the exact same thing, it flows into the "ground". The battery is getting drained just like the water tank. The regulator sees this and tells the alternator/generator, hey the battery level is dropping I'm switching you on and filling the battery back up.

Now If you had to diagnose your water pressure system you would need two tools to test it. A pressure gauge and a bucket to see how much water is flowing. You can see the water, you can touch the water.You can watch it flow. You can see how fast its flowing, how much of its flowing. You can measure the pressure with a gauge. You can see how fast its filling up a bucket with a watch. You visually see this all happening and it easily makes since. Electricity is like magic, you can't see how the trick was performed. How are you going to understand it if you can't see it? You can't see it or can you? You can see it, with a meter. It tells you how much current is flowing. It tells you how much pressure (voltage) there is. It tells you when where there is resistance and how big it is. It is so easy to use but nobody will take a day to sit down and play with a meter to learn this stuff. Your not going to hurt anything. Except, don't set the meter to the resistance scale and try measure something with the voltage still present. You will low a fuse in the meter. Other than that you can't hurt the meter and you can't hurt anything your testing.

I want you to understand this stuff first. Then I want you to watch the voltage drop video.

The amps are the same as the water flowing in the pipe. Amperage is "how much electricity" is flowing through the wire/circuit. 50 amps is more electrons flowing than 20 amps. The Voltage is the pressure, just like the water pressure in your hose. 12 volts is more "pressure than 6 volts. Resistance is the same as the blockage in the pipe or a kink in your garden hose. If there is a kink in your hose you loose pressure at that spot, your hose would barely get a spray out of the hose, If their is a bad spot in a wire, switch, connection or device the voltage pressure drops at that bad spot. Not as many electrons (amps) can flow through that restriction. With a voltage meter you can find where that drop in voltage is.


This is a 14-minute YouTube video on voltage drops. There are a bunch of them on YouTube. I grabbed this one because it looked like it my decent. If it doesn't make since watch over and over until it does. Then go fix your truck.

Last edited by Flathead Fever; 01-26-2019 at 03:49 PM.
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Old 01-26-2019, 04:03 PM   #29
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Default Re: engine won't turn over

Quote:
Originally Posted by hook00pad View Post
I rebuilt the engine in my 4 cylinder Ford Courier years ago, cleaning and painting everything. When I tried to re-fire the engine, I couldn't get the starter to spin it freely. Thinking it was just tight with new bearings and seals, new bore, pistons and rings, etc. I connected a high-current battery charger to the battery and tried it. The battery exploded blowing the plastic top and battery acid everywhere, luckily I wasn't standing directly over the battery.

Well, after I cleaned up the mess and got the battery acid off of me, I started checking connections. As it turned out, the problem arose from a poor ground at the engine block from all of that pretty engine enamel. I'm guessing that a spark from connecting the charger set off that little Hydrogen Bomb! I'm talking about a blast that sounded like a shotgun blast almost in my face. I considered myself lucky, with no injuries.

I was a lot younger then, as well. Ha ha

Al Hook

A voltage drop test would a meter would have found that painted connection (resistance) in less than five-minutes. I'm sending you to voltage drop school too. read my other post.


I was driving a Ramcharger back to the shop on the freeway when it blew-up the battery. Your not kidding about the shot gun blast. I though I just been killed by drive by gang member or somebody that hated the phone company had shot me, which was more likely. The funny thing was the Ramcharger kept driving. When I got to the shop the top of the battery was completely gone and I could see all the lead plates and the acid just sitting in there. I knew something was wrong a few miles before it happened. All of a son the headlights got extra bright. The regulator went bad and the alternator was charging way too many volts. Something internally would have to had sparked inside that battery. In 30-years and thousands of fleet vehicles that was the only battery I ever saw explode. My dad had one explode on a Marketeer electric cart out at Kaiser Steel. It blew the back of the cart apart. Those are really big deep cycle catteries. You can barely lift one.
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Old 01-28-2019, 08:07 AM   #30
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Default Re: engine won't turn over

Some good knowledge on this subject, Thank you.
I should mention that after running for roughly 15 minutes and I shut the engine off it won't turn over using the starter button. I took the spark plugs out and it turns over good using the start button. Also could turn over using a hand wrench very easy. Is it possible to have too much compression when trying to start with a hot engine with the spark plugs in ?
I'm really thinking it's a electrical issue, too much resistance in wire or connections.Note, it is a new starter.
Next step will be removing the starter and cleaning all connections.
Most likely can't do till next week.
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Old 01-28-2019, 08:37 AM   #31
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Default Re: engine won't turn over

I have a '69 Hurst Olds with a 455 that is far from stock. I was having the same problem. I mounted a second solenoid near the battery and increased the size of the cables to 3 ought. No problems now.
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Old 01-28-2019, 10:44 AM   #32
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Default Re: engine won't turn over

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Originally Posted by Flathill View Post
Some good knowledge on this subject, Thank you.
I should mention that after running for roughly 15 minutes and I shut the engine off it won't turn over using the starter button. I took the spark plugs out and it turns over good using the start button. Also could turn over using a hand wrench very easy. Is it possible to have too much compression when trying to start with a hot engine with the spark plugs in ?
I'm really thinking it's a electrical issue, too much resistance in wire or connections.Note, it is a new starter.
Next step will be removing the starter and cleaning all connections.
Most likely can't do till next week.

No need to keep guessing. Remove, clean and tighten ALL electrical connections in the starter circuit. Run it for 15 + minutes. Check battery voltage while cranking. Do a starter amp draw test. Do a voltage drop test.
If it were too much compression (only if this is a hot rodded engine) it would crank for a half turn or so then slow down or stop, then crank again after a few seconds; it would not be locked up tight.
Loosen the starter mounting bolts and jiggle he starter then re-tighten. It's possible the starter is bound up if the bolts weren't tightened evenly.
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Old 01-28-2019, 11:22 AM   #33
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Default Re: engine won't turn over

Why not just jumper across the starter solenoid? That removes the solenoid from the circuit and checks everything else.

Update: 40 Deluxe posted a good check procedure to check out the system.
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Old 01-28-2019, 07:28 PM   #34
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Default Re: engine won't turn over

An old trick is to put your hand on the various components and feel for heat. Usually when something heats up, that's your culprit. Do this right after trying to start it when its hot. Also load test the battery.
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Old 01-28-2019, 11:00 PM   #35
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Like 40 Deluxe said. You need to see how much amperage your starter is drawing while its cranking. You need to be able to see how low the battery voltage is dropping while the engine is cranking. Without a meter your just guessing at the problem.
Even if you wiggle a connection and it starts cranking and you might think you have fixed the problem. You just made it "good enough" to crank. You still need to be checking all the other connections, cables and switches for resistance by doing a voltage drop test. These old cars will have resistance everywhere, unless somebody has completely gone through the electrical system. All those little drops in voltage, 1/10th of a volt in a cable, 3/10ths of a drop at a connection, 1/2 volt drop across an old switch. It will crank when its cold but it might not crank when its hot because heat can create more voltage drops. A 6V starter already cranks slow, you can't afford to have it crank any slower. You can clean all those connections but you still will have no idea what is going on inside those cables or how well the ends are crimped on. The volt meter is your eyes to see what is going on inside there.

I'll give you an example of a problem that stumped an entire Ford Dealership's team of mechanics and the Ford Technical Guys in Detroit they sent out to diagnose it. It was an intermittent cranking problem on a brand new car. The vehicle had been back several times for this intermittent no cranking problem. It was hard to duplicate the problem. They replaced the starter, relay, battery, ignition switch.... Each time the vehicle came back. They were going to have to declare it a "lemon" under the CA law and buy the vehicle back. What eventually fixed it? No mechanics I worked with understood anything about voltage drop testing in 1980.What happened was the The State of CA came along with their smog test program and forced the smog tech mechanics to get better educated by having them tested to renew their smog licenses every two-year's. One of the first things to appear on those tests were questions about voltage drops, ohms law all kinds of electrical diagnosing with meters. The phone company required all of their mechanics to have smog licenses or they were fired sixty-days after your license expired. You had a good incentive to learn this stuff.
Getting back to the new car with the cranking problem. A mechanic that had just learned about voltage drops started checking every connection, part and cable in that starter circuit. What he found was when one of the battery cables was made the insulation was not removed from the end before the end was crimped on. It was crimped on hard enough that it made a connection most of time but when it warmed up the insulated end prevented it from cranking. I would not have thought to replace it, its a brand new shiny cable, what could go wrong with it? It was bad and only a voltage drop test stopped Ford from having to buy back that vehicle.

I should know the specifications for a 6V battery load test but I don't. I've never had to load test a 6V battery. I don't know how much amperage to apply and how low the voltage is allowed to drop on a 6V battery?

I'm using a 12V system as an example because I have done this battery load test literally thousands of times on 12V systems. First you charge the battery to make sure you have a full charge on it. Then you disable the engine so it will not start. You have your voltmeter already hooked up to the battery terminals. Then you crank the engine for 15-seconds. The battery should not drop below 9.6 volts the entire time you are cranking. Then you wait 15-seconds for the starter to cool down and you crank the engine a second time for 15-seconds while watching to see if the voltage drops below 9.6 volts while it is cranking. If it drops below 9.6 volts the battery is junk.

You should do battery load test before you start the car and again when it does not want to crank.

The only problem with doing the above test using the starter to create the load is you do not know how much current the starter is drawing? You could have a bad starter or a engine that gets tight when it warms up. That could cause the starter to draw too much current. That would drop your battery voltage during your load test to below 9.6V. You could have resistance in the circuit and then not have enough amperage flowing to correctly load test the battery. That is why you need to know how much amperage that starter is using. Most guys are not going to have an ammeter at home that can read 300-600 amps. Those meters will a lead that clips around the positive cable on a negative ground system. It senses the magnetic field around the battery cable while the engine is cranking and converts that into a amperage reading you can see on the meter.

You really need to isolate the battery to test it properly. Your at a big disadvantage at home. In an automotive repair shop you have a machine that simulates the correct amperage load to check a battery. You find the Cold Cranking Amperage of the battery, it's usually on the decal. Then you use the machine to put a load on the battery that is equal to "half" of cold cranking rating. You apply the load for 15-seconds. Then a 15-second rest and then the second load test for 15-seconds. If it drops below 9.6V the battery garbage. If it holds at 9.6V its marginal.

You never want to crank any engine, antique or modern for more than 15-seconds. The armature can get so hot that the solder can melt out of it. You need to give it a rest so it can cool down between cranking.

This is test you can do without any tools if you think you have a bad a battery.
At work we had large round mirrors mounted up high on the walls so that when we pulled into the stalls you could see all the lights around the vehicle without getting out. The mirrors were also good if you were by yourself for doing quick battery test. If you had a starting problem you would watch the headlights in the mirror from inside the vehicle while you cranked the engine. If the headlights went dim or out when you tried to crank the engine you most likely have a bad battery or a battery that is not being charge. If those headlight stay bright and it does not crank you probably have a starter problem. If your in the middle of nowhere, stuck with a bad starter you can almost always get a couple more starts out of it by having someone crank the engine while you crawl down under there and smack the starter hard with something. That will get you home but it usually only good for a couple of times then the starter completely dies.
That is something you can try when yours does not crank.

You need a Volt Meter to check to see if the battery is being charged. It should be around 12.6V fully charged. When you start the car the voltage should go up to 14.2V. If you have the voltmeter and ampmeter hooked up you can literally run the battery load test, alternator charging test, and check the starter current draw in about one-minute.

I hate to see people waste their hard earned money. I see it all the time with my neighbors. I had one not ask me for help. Everybody wants to be a mechanic but nobody wants to know how any of it works. This guy bought a starter, relay, battery ignition switch..... He messed with it for a month. It turned out the problem was one of those stupid aftermarket dealer installed alarms that went bad. I bet I've seen a dozen of them do this. The problem could have been found with a voltmeter. The alarm tossed in the trash. The repair costs would been free. He could have bought several voltmeters with the money.
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Old 01-30-2019, 01:11 PM   #36
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Default Re: engine won't turn over

Just made a post and lost the whole thing ? Try again. All good suggestions. I will jump a cable across the solenoid when starting and see what happens. Also will clean all connections, check voltages when turning over the engine and reread and think about the other comments. May try a good remote ampere meter and record readings. Large cable is in place from battery to solenoid and then to starter. Looks like copper welding cable. May be size 00.
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Old 01-30-2019, 03:31 PM   #37
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Default Re: engine won't turn over

Flathead fever has given an excellent presentation on understanding electrical theory. Print it for future reference.

The analog (needle) voltmeter is excellent to determine voltage drop or loss, which is caused by resistance in the circuit. Connect the negative lead do the meter to the negative terminal of the battery (not the cable terminal) and the positive lead to the terminal on the starter. Meter should show 6.2 volts or more. Now hit the start button (have wife help) and the meter should show no more than 0.1 volt. If more then move the volt meter lead off the starter to each terminal on the starter relay (switch) in succession. Also, check the ground side of the circuit by connecting the positive lead of the volt meter to the psositive terminal of the battery (not on the cable terminal, but to the battery post) and the negative of the volt meter to the starter case. Now hit the starter button ( need wife to help). Again the reading on the meter should be not more than 0.1 volt. ALL TERMINALS NEED TO BE CLEAN AND TIGHT!!!! You will find where the problem (voltage loss) exists.

Another thought - are you using a group 2 battery? I used a goup 2 battery and I now use a 6 volt Optima. Really does the job.

You want 6 volts to get to the starter and the voltage drop takes away from the 6 volts. The less voltage drop the better!!!
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Old 01-30-2019, 05:05 PM   #38
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Default Re: engine won't turn over

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Just made a post and lost the whole thing ? Try again. All good suggestions. I will jump a cable across the solenoid when starting and see what happens. Also will clean all connections, check voltages when turning over the engine and reread and think about the other comments. May try a good remote ampere meter and record readings. Large cable is in place from battery to solenoid and then to starter. Looks like copper welding cable. May be size 00.
First make sure the car is out of gear and the ignition is off!

I can't remember if you said that if when its hot the starter Bendix is or is not pulling in and engaging the flywheel, but not cranking?

I imagine this is still a positive ground system since its still 6-volts. So everything is backwards from what your use to. It messes with my head too. I'm so use to working on negative ground systems.

I always breakdown an electrical diagnoses into four sections. There is the battery. There is everything between the battery post and the starter terminal. Then there is the starter (the load). Last everything between the starter ground (the housing) and the ground terminal of the battery. You go after each one of these separately. Just work on one section at a time Don't worry about any of the rest of it. You go after what you can check for "free" first before start assuming a part is bad.


1. You always start with the battery. Because 95% of the time that's where the problem is. You can check it for free by turning on the headlights and seeing if they go out when you try and crank it. Both when its cold and when its having the problem. If the head lights go completely out the battery could be bad or discharged. You should check it with a voltmeter but if you don't have one the headlight test is better than nothing. I have not read where you have tried the headlight test. Try the headlight test on your daily driver and see what they do. It will give you a good idea of what a good battery should look like.

You should still go out and buy a meter. Right this minute! There are some really cheap digital meters. They will probably work for you need. "Do not" use them on a computer controlled vehicle. Do not use an analog (with a needle) on a computer controlled vehicle. The circuits are literally microscopic inside that computer. The meter, just by itself can draw enough current though those tiny computer circuits to damage them. You have to buy a meter that is designed for working on computerized cars. Most people buy a Fluke meter that work on vehicles for a living.

2. Now were stuck you can't do this test without the voltmeter. But you went out and bought a voltmeter so now we can continue.

You need to know how to setup your new voltmeter. The one you just bought!
This is how hard this is. Stick the batteries in the meter. Turn on the meter. Turn the voltage scale switch on the meter to the next higher scale than the voltage you want to test. I think I use the 30 Volt scale when I'm checking for 12 volts. If you have it on the wrong voltage scale it won't hurt a thing. Your reading will just be screwed up. On the second switch You have an AC and DC scale . AC is for the house DC is for your vehicles and batteries. Turn the switch to DC. You have two leads, one red, one black. You have a plug marked common or the "-" symbol, stick that black lead in there. Now you probably have two holes left, One for amps and one for volts (+). You might not have the amps plug on a cheap meter. Even better, you will never use it. Plug the red lead into the (+) hole. You are now ready to go. You cannot hurt the meter except on the resistance scale. You do not check for resistance while voltage is present. Its best to just disconnect the battery cable. Resistance is the little omega symbol. Don't plug anything in there and your good. Maybe one more thing I should mention, you should not use your new meter as an ammeter on a large circuit. For now its just better you never use it Never disconnect something and then put you meter leads between those two disconnected spots. When you do that all the amperage will try to got through your meter and it cannot handle it.

You will never use the resistance scale unless your measuring the specification of a resistor. The only time that will happen on an old car is on the ignition resistor. So forget all about ohms and all that stuff. You should eventually know it but for now don't worry about. Without going into it too deep you cannot check the resistance of a battery cable with a ohm meter to see if it is good. I'll give you a quick example, you check the resistance with your meter on a battery cable and it says its good , zero resistance. Is it really good? Your putting a tiny bit of electricity through the cable from the voltmeter's batteries. Its going to have no problem finding its way through that giant cable, even if the cable is 99% bad. The meter is going to read zero resistance because there is zero resistance for that tiny amount of electricity. What happens when you crank the engine and your pushing 300 amps through that cable. That 99% bad cable is not going to be able to handle it. Its like a plugged water pipe. A trickle could get through the pipe but not a flash flood, 300 amps is like Niagara Falls trying to flow through that cable.

Yes, electricity flows just like water. If its not flowing it won't spin the starter. If not enough flows it turns too slow or not at all. The only way we can check the cable for resistance is to do a voltage drop test. That just means checking for how much voltage is not getting through that cable when the starter is trying to crank. How do you figure it out? You stick your leads on each end of the cable while your cranking. Your voltmeter reads 4.00 volts. What that means is only 2 volts of pressure is making it through that cable. Remember voltage is pressure. Its not some kind of magic, its the measurement of electrical pressure. Don't overthink it.

The meter just feels the 4.00 volts of pressure that cannot flow through the cable. Just like a water pressure gauge. You can't see it and its too small of a pressure for you to feel it but its there. The meter tell you it is. If you don't believe there is electrical pressure in a circuit try higher pressure, like a spark plug wire. We started with 6 volts of pressure, 2 volts made it through the cable 4.00 volts did not. We now know where that 4 volt blockage is. What do we want to see in a cable, we want to 0.00 volts. zero pressure in that cable, zero resistance while its operating the starter.


If 6 colts leaves battery. We need to be able to find all six volts in the circuit. We do the voltage drop test. Every little pressure drop should add up exactly to the pressure that's in the battery. Ideally the only pressure drop would be the starter. If you put the leads across the starter while its trying to crank you should see almost the full 6 volts of pressure being used at the starter.



Go get a flashlight, 9V, AAA what ever you have. Lets say its a 9V battery. Stick the red lead on the plus side of the battery. Stick the black lead on negative side. The meter should say 9.00 volts. That have now mastered the DC voltmeter. You don't need to know anything else about it except to turn it off when your done. I take the batteries out of mine.



Perform voltage drop tests across "every single" big cable, little wire, connection point, switch, wire spice, , starter solenoid. foot mounted starter switch, anti-theft devices…. Every spot where separate parts touch each other. Then test every one of those separate parts. Everything between the negative battery post and the terminal on the starter. That includes a wire and its crimped on end. That includes a drop test between the battery post and the battery cable end, that is very first spot you would start. Then you just keep moving towards the starter doing voltage drop tests. If you find a drop you clean the connection or replace the part.
3. The other side of the circuit. which in this case is th positive ground side




You could jump a cable from the "negative" battery terminal directly to the starter post connection. Make sure you connect to the battery terminal first. That's a lot of amperage going through that starter cable. Its going to spark a lot, like a welder, when you first start to clamp onto the starter terminal. If this spark were to occur at the battery you could have an explosion. Especially if you have been charging the battery and its "gassing" ( when you can smell the battery fumes) this is a sign that you are trying to overcharge the battery or charging with too high of an amperage. If you can smell those fumes so can that spark, and it could do the boom-boom! That's what I tell my one-year old grandson a hundred-times-a-day, "your going to do the boom-boom"! You want to control where that spark occurs, better it happens down at the starter. If there is no spark that already tells you something is wrong, for some reason the current cannot flow. Bad starter or bad positive ground side of the circuit. That tells you its not a tight engine or it would be sparking as the current was trying to crank the engine

It sparks because as the jumper cable clamp starts to make contact with the terminal all that amperage is trying to flow through those tiny contact points, the treads on the terminal lug and the little tips on the jumper cable clamp. The amperage starts melting them (its a welder at that point) until the clamp can make a good enough connection that the amperage can finally all flow through it. You might freak out as soon as you hear the cracking boom of the electricity jumping the gap. Its a miniature version of thunder, at the same time it look likes you have just done something really bad. You have not, its normal and it will stop as soon as cable clamps with enough pressure. One warning, if the cable starts to glow red and smoke rip that cable off as fast as possible. Then go bandage your burned hand. It happens instantly. You have a complete short to ground inside the starter.

If the starter is good and the "positive ground circuit" is good, the starter should spin, unless the engine is locked-up which it sounds like it is not. I was thinking, just for the fun of it, you could put a torque wrench on the crankshaft pulley bolt and compare the torque needed to rotate the engine when it is cold and then again when its hot. It would be interesting to see if there is any difference?

Back to the starter. If the starter still does not spin take the other jumper cable and "first" connect it to the positive terminal on the battery.Make sure the starter bolt is clean and bare metal. Take the other end of the cable and clamp it directly to that starter mounting bolt. It could spark again as you complete the circuit. It should crank if the positive ground side of the circuit is bad.

Now you have bypassed everything there is in the entire starting circuit except the battery and the starter. If the battery is good than the starter is bad. Like I said in previous post you can try tapping on the starter with a hammer and it might spin but its still bad. You don't want to try and return a starter you have beat the crap out of. The hammer, rock or whatever you can find to beat the hell out of the starter trick is for emergency situations when your prospecting in the desert 50- miles from civilization. It usually only works one time so don't shut off the engine again. Somebody has to be trying to crank the engine at the same time you hit the starter.

Make sure you have good battery cables. I grabbed a cheap set at work one time and they were no good They had an open inside of them. That really messed with my head until I figured out the cables were bad. After that I only bought the best quality jumper cables I could find. Heavy cable with good quality clamps on the end with lots of clamping force.

Its taken most of us gearheads 50-year's or more to buy all the tools we use and there is never an end to it. I tell a guy to grab a torque wrench ,voltmeter, jumper cables and we just assume everybody else on the planet has this stuff. Why would they have stiff stuff if they never worked on cars before. If your young and you think your going to continue to work on cars as a hobby you need buy these tools as you need them. I don't borrow tools or rent them. If I need a tool, I go buy it. If I use it once, it probably paid for itself. If you don't need the tool "right now" buy them used at Estate Sales and Swap Meets. You can buy ten-times the tools for the same money, quality tools. You can buy those big heavy America Made tools that nobody wants to inherit because they are hard to move and they take up too much room you can buy for a fraction of the cost. But you need to be there first inline at the Estate Sales or Swap Meets to get the deals.

Last edited by Flathead Fever; 01-30-2019 at 06:58 PM.
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