Starter Cranking Problems for NH L220

[51kw]

I still have money on a bad connection.

 

[Delmer]

Anyone know of a good way to test that wire to see if it has enough amp capacity??
\

Run a test lead (wire with an alligator clip) to the solenoid terminal, and hook that up to your multimeter to see what kind of voltage is there when you try to start it and it doesn't crank. If you get 12V there with no cranking, then move the test lead to the battery cable, either going into the solenoid or into the starter. If it follow the voltage you'll find it soon enough.

 

[durallymax]

A DMM with min/max will be able to monitor the voltage at the starter "s" terminal.

 

[Delmer]

Yep, or you can hold the click, that is keep the key in the start position, and check the as many voltages as you have wires run to.

 

[StumpyWally]

Weather cooperated today, so I reinstalled the starter, did extend & eliminated the sharp bend in the ignition/exciter wire. Machine started right up. I try it again tomorrow.

Thanks for all your opinions & advice. I haven't found any loose or bad connections yet. My DVOM does not have a min/max function...that would be helpful. Also, I do not have an IR temp gun. Didn't I tell you guys that I'm not a professional mechanic...

Also, there is no "hold the key in the start position", since it's a keyless ignition...I'd have to press & hold the start membrane switch, & would need another person to check voltages. Will probably wait until my son comes over on Sunday & maybe we'll have a go at it...

Finally, just checking for voltage on the ignition wire I don't think is enough. If some wire strands are broken, the remaining ones would suffice to give a voltage reading, but would probably not be enough to pass the required amps to get the starter going.

 

[bobcan]

Hey Stumpy.. That sounds like positive news in general, hopefully it is a FIXED thing, and not just a 'started working all of a sudden' _ Electrical Faults can be annoying, and every time I get something figured out I try to remember the Issue and Procedure that got me there _ sadly, I often forget it seems.. Ha!!

Take care, thanks for the updates _ and I am NO real mechanic either, but always enjoy reading and learning and trying to share with others here _ Have a GREAT weekend all!!

 

[Delmer]

If some wire strands are broken, the remaining ones would suffice to give a voltage reading, but would probably not be enough to pass the required amps to get the starter going.

No, that's why you use a test lead to check the voltage under LOAD, either the voltage is good enough at the solenoid terminal and the starter is the problem, or the voltage is low and the "ignition" circuit is the problem. Loose connections can be crazy to figure out, but if you can check the voltage while it's doing the problem under load then that clears up the confusion. UNDER LOAD there is no "good voltage but not enough amps".

Hopefully it's good for now, but just in case it's not...

 

[durallymax]

Weather cooperated today, so I reinstalled the starter, did extend & eliminated the sharp bend in the ignition/exciter wire. Machine started right up. I try it again tomorrow.

Thanks for all your opinions & advice. I haven't found any loose or bad connections yet. My DVOM does not have a min/max function...that would be helpful. Also, I do not have an IR temp gun. Didn't I tell you guys that I'm not a professional mechanic...

Also, there is no "hold the key in the start position", since it's a keyless ignition...I'd have to press & hold the start membrane switch, & would need another person to check voltages. Will probably wait until my son comes over on Sunday & maybe we'll have a go at it...

Finally, just checking for voltage on the ignition wire I don't think is enough. If some wire strands are broken, the remaining ones would suffice to give a voltage reading, but would probably not be enough to pass the required amps to get the starter going.

Yes I had a different issue in mind when I typed that apparently, you want to monitor the voltage that is at the starter, then check it again at the battery. If it's dropping at the starter but not the battery, the battery is good and the cable is bad.

You need to test the connection under load, the load being the starter. Bad cables can certainly handle the small loads and keep a voltage reading fairly high as can bad batteries, but as soon as you apply the load you will see a significant drop if one of them is bad.

You don't have to have min/max, just need longer test leads then so you can watch the meter yourself

 

[melben]

It sounds like you have a voltage drop in the solenoid energizer wire to me , this was common in the Case skid steers that used the Nippon starters. If it starts feeding the solenoid terminal direct from the battery add a relay to energize the solenoid in the starter.

The reason it acts as it does is the battery voltage drops enough overnight to not pull the starter solenoid in, after the first start the unit would work normally all day and repeat the problem next AM.

In the Cases the wire size to the solenoid was marginal and introduced voltage loss to the solenoid. You might test the voltage at the small solenoid energizer wire when cold if the problem returns.

In our situation a relay cured every one we installed one.

 

[StumpyWally]

About 5 days ago I thought I found the problem. When it failed to crank one time, I measured less than 0.5v in the ignition wire at the starter, so I felt pretty sure it was the crank relay. So I replaced that relay with a new one. For the next 2 days it cranked without fail multiple times each day, then on the 3rd day it failed to crank several times. Again, I measured less than 0.5v in the ignition wire at the starter when it failed.

Have done a bunch more testing, which I can summarize as follows:

• Ignition relay is an Omron automotive-like, sealed relay, so it can't be examined inside without destroying it.
• I've tested the relay with an external 12v source, & its coil energizes & closes its ignition circuit repeatedly without fail.
• The relay socket has a constant 12.5v input on the correct pin.
• When the start button is pressed on the panel, even when it fails to crank, there is about 11.7v applied to the relay coil to close the ignition circuit.
• The ignition wire from the relay to the starter has continuity, & I've measured about 9 amps thru it when I crank the starter by manually applying 12v to that pin in the relay socket.
• I haven't been able to define any pattern to when it will fail. It's worked & intermittently failed when the weather has been 50*F or so, & when it has been below freezing. It was cold last night & it's cranked without fail today over 6 different times.
• Although I've already ruled out the battery, I have recharged & reconditioned it with a new Optima 1200 charger. And I have a Battery Tender hooked to it constantly to keep it charged.

So, I'm stumped...this isn't brain surgery, & the engineer in me is really frustrated 'cause I can't find the problem, let alone fix it!!

The only possibilities I can see are:

• Both the old & the new relays are intermittently bad.
• or, there really is an intermittent problem in the starter, despite me having it tested & inspected by a starter shop.

The next time it fails to crank, I plan on removing the relay & manually applying 12v to the ignition wire pin in the relay socket to see if that will crank the starter. I've done this successfully already but only when it hasn't failed to crank first.

Baring some conclusive result from that test, I may have to just live with it until it fails to crank consistently. But with my luck, that will be in the dead of winter when I rely on it to plow snow!!

 

[bobcan]

Well, without knowing more/standing there and looking at it, I gotta think you have tested a LOT an provided good info back to folks here.. That being said, the only thing that immediately comes to mind is that you have ".. tested the relay with an external 12v source, & its coil energizes & closes its ignition circuit repeatedly without fail. ~ The relay socket has a constant 12.5v input on the correct pin .." so I will provide the thought of checking the REAR of the Relay Socket (is it push on-crimped connectors, or Soldered..??) and see if the connection might be Loose at all once the machine gets banged around a bit and now show what appears proper Voltage but not enough Current perhaps, once it is needed..?? ** and sorry, but I do NOT know what that Required Current would even be, but doubt it is a huge amount to energize the Solenoid..?? Perhaps a wiser man will tell us _

And, other that that, of course if you have not been all the way through the Loom and its Connectors, you could always Take Apart and Clean ANY and ALL Connections along the way, 'just because it will not hurt your cause' and is more fun now than a windy January day _ and one might be the culprit!!

Once again, Good Luck there, and thanks from a guy who likes to learn about these from others, for keeping us all in the loop _ Stay Well and Warm!!

Once again,

 

[melben]

Can or did you take a resistance reading of the solenoid coil circuit from the tab of the starter to ground? What do your calculations come up to when applying OHM'S law to the voltage and resistance readings? That should tell you what the amperes draw of that circuit should be.Try taking a wire from the battery stud on the starter and go directly to the tab where the energizer wire from the switch goes. Has someone added a relay at the starter already to take heavy current from the battery stud to the starter tab already? Where is the relay that you are referring to located? When we added the Bosch style relay and harness we did it right at the starter.

I had a 1840 do what you describe and it turned out to be a intermittent ignition switch on the start blade of the switch, so if you have not looked at it you may consider that, if the problem can be duplicated with the dash down a reading on the rear of the switch at the start terminal could be telling.

 

[StumpyWally]

melben - The crank relay I refer to is in the fuse box at the lower left of the cab. The "ignition switch" is a membrane-style push button on the keyless ignition panel at the upper right of the cab. As I mentioned in my post #30, "When the start button is pressed on the panel, even when it fails to crank, there is about 11.7v applied to the relay coil to close the ignition circuit." So, I doubt the problem is with the start button. But thanks for the thought.

 

[melben]

Stump, is the relay in the starter circuit sending battery voltage to the starter tab. Since you have a key less setup quite possibly there is a starter relay that sends voltage to the energizer tab on the starter. Have you measured that voltage at the point of failure to see if the starter is getting the needed voltage? I do not know what starter the NH used but do know that the Nippons that I am familiar with need a hefty amount of voltage to work reliably. If you have already posted that info forgive me as I have not read all the back posts. Interesting thought that the system may have a low cutoff voltage system.

Mel

 

[Jonas302]

You had 11.7 volts on the coil when pushing start did you check the ground path for the coil also there may be something that has to be closed in the ground path to allow starting like a seat switch or such

 

[melben]

I have seen intermittent lap belt sensors, had to replace the RH part of the strap.

 

[StumpyWally]

melben & Jonas302 - The crank relay I refer to is in the ignition circuit, that is when you push the start button, that's supposed to send voltage to close the coil in the crank relay (I've checked that voltage on a button press & it seems OK), when the coil closes it allows the constant 12v on one pin of the relay to flow out the ignition wire to the starter (I've checked that voltage & it seems OK). The Denso starter has 12v constant to its main lug.

The seat switch only needs to be pressed (engaged) in order to start the power on/preheat cycle. Once that's complete, you can then press the start button, regardless of the seat switch status. The lap belt only needs to be buckled in order to press the operate button to release the brake. Of course the seat switch needs to be engaged also to have the brake release. So, both the seat switch & the lap belt are not part of the crank logic once the start button is pressed.

As I've posted previously, I've stopped trying to diagnose further until in the normal course of my intermittent usage of the machine, it fails to crank. Then I'm going to try to pull out the crank relay just enough to jump 12v around the relay into the ignition pin of the relay socket, while I observe voltage at the end of the ignition wire at the starter. If I get 12v ignition at the starter (which I expect, since I've previously ran at least 9 amps thru this wire), & the starter does NOT crank, then the problem has got to be in the starter, despite my local starter shop's determination that it's good. Remember, the main lug of the stater has 12v to it all times, which I've verified by measurement & tracing of the cable from the battery.

If the starter DOES crank, then I think I'll still be puzzled, because:
- the direct, reapplication of 12v to the ignition circuit might have been enough to "jar" the starter or it's solenoid off its dead spot,
- or the crank relay might still have failed the 1st time,
- or the start button might have failed to send the coil closing voltage to the the crank relay that 1st time.
So, I might just have to live with the intermittent problem until it becomes constant. If that turns out to be my only choice, I can't express in words how frustrated & mad I will be!!

 

[Jonas302]

I understand your frustration I just wanted to make sure you have checked the ground path for your relay coil I feel like maybe you have but just to make sure you have to have a ground path at the time of cranking even though you get a power signal from the start button doesn't mean the ground path is open it might be switched seat switch is just an example it can even go though another relay I understand that you dont have a diagram it would help immensely By the way you might be interested in a relay tester http://www.lislecorp.com/divisions/products/?product=545 you can set up a remote test light to the relay and or the starter start terminal something you can see in the cab at the time of failure might help shake out the problem

 

[melben]

Stumpy,

That was the issue we had with the Nippon starter when we updated older units from the old Delco starters. The neutral start wiring was not heavy enough to handle the solenoid draw but the unit could be started reliably with a jumper from B+ at the starter. We put a common BOSCH RELAY right at the starter with #10 leads from tab to relay and from relay to B+. The old wire from the dash had only to carry enough to kick in a tiny coil to transfer heavy current to the tab.

I may be on the wrong track but your problem exactly mimics the problem we had when converting older units, the Nippon solenoid draws way more current than the Delco did.

I would be interested in the results a direct jump test and if know, the resistance of the solenoid coil and the voltage applied would give the info needed to compute needed amperage which I am quite certain would be greater than 9 amps. Or if the true solenoid coil resistance is know the required amperage can be determined

In fact, I have a New Nippon that I will try to get the ohms of the solenoid coil and do some math. Some quick math using your figures of 12V and a wire drawing 9 amps at engagement would mean the resistance of the solenoid windings would be 1.33 Ohms. When bypassing at the starter it may be telling to put an ammeter in the jumper, I suspect much more amps solenoid draw.

These things can really be aggravating.

Good luck, Mel

 

[Delmer]

When the start button is pressed on the panel, even when it fails to crank, there is about 11.7v applied to the relay coil to close the ignition circuit.

That should have tipped us off, the voltage shouldn't drop that much with just the "dash" on. Melben's suggestion is making more sense all the time.