1986 Case 580 frustrating no start/no power to gauges

[Nick Tonelli]

I have a 1986 Case 580SE and have bee having some intermittent difficulty starting occasionally the machine would go dead and starter would click like a low/dead battery. Sometimes tach would bounce all over the place but now machine is no completely dead in water, I was able hook jumpers to starter and it started right up multiple times but now that does nothing for me. When jumping the starter solenoid it would only click.

Some additional info:
- Brand new battery
- 10.4 volts to starter (is this normal?)
- neutral safety switch has continuity
- grounds checked, cleaned and re-tightened

I followed this thread as the guy had the same exact symptoms as me. My cab harness has similar symptoms to him while all connections looked great the red wire had some corrosion at connection. I bypassed harness with heat shrink, butt connectors and 10 gauge wire but no change.

580e problem! no power to ignition

i have my 580e, replaces the ground strap and cables not long ago, batteries were weak so i was jumping the one side, it cranked for about a second, didnt kick over and then letting off the key i heard a sizzle under the dash, now i have no power to gauges, or ignition switch, pulled the switch...

www.heavyequipmentforums.com

Based on the thread I linked above I have the 3 relay wiring harness as I have no inline fuse behind starter and no big relay that I could find. I tested the three relays across the 85/86 contacts and they have continuity. I also checked the 5 circuit breakers and all have continuity

While inspecting the cab harness connection there was no visible wear from rubbing the top of the bellhousing that might cause a short.

My machine has some rust but the electrical connections are all in really good shape, I quadruple checked the grounds (that I could find) especially the battery ground and its clean and secure.

With test light I have power to accessories contacts on ignition switch but test light shows no power to ignition contacts on the switch. I use to be able to jump the starter solenoid but today it won't do anything. I swapped out with a new starter and nothing has changed

I might be providing a lot of confusing (even conflicting) information but I've tried in earnest to diagnose and remedy myself and search this forum for similar results but have come up empty handed and confused. I'm very 12v naive.

 

[Delmer]

Keep it simple, are you comfortable with how a digital multimeter works? if you are, start at the battery and check the voltage. Then check at the starter, lets say at the positive terminal on the solenoid from the starter and the body of the starter, will be the same as the battery. Then get someone to crank it, or hook up test leads with alligator clips to see the voltage while cranking, if it clicks that voltage will probably go to 0, if it does go to 0 then work your way back to the battery one step at a time until you find the voltage drop. If it stays 12V with the click and trying to crank, then check the other side of the solenoid going into the starter.

Basic troubleshooting, you start one place and work logically through the circuit until you find a problem. You may have several problems.

If you're not real comfortable with a multimeter, then a power probe is an excellent investment for troubleshooting like this.

 

[Nick Tonelli]

Not very well versed but competent. Forgot to check while cranking will do that tomorrow to help narrow down terrible spots thanks

 

[franklin2]

I will 2nd that. Always check for voltage while trying to crank it over. It may take two people.

 

[thepumpguysc]

When working alone, as most of us are..
Get yourself a “remote starter button”.. u hook up the alligator clip to the big lug on the starter and the other clip to the small spade..
As long as the machine is in park/neutral you can crank it all day.!! (Push button)

 

[HarleyHappy]

Just check your neutral safety switch, jiggle the lever back and forth while cranking.
Mine acts up occasionally.
It does sound like the starter solenoid.
Mine does this occasionally also and I jump it at starter with a screwdriver.
Will need to fix before winter.

 

[Nick Tonelli]

Voltage dropped from 11 to 8.4 while turning ignition on - it didn’t even try to crank.

Neutral safety switch is fine I jumpered the connection and nothing changed.

Tried jumping the starter from main lug to ignition and it just clicked. Installed new starter and tried jumping same way and it also just clicked

 

[Delmer]

Voltage at the battery or at the starter? Does the engine turn by hand?

 

[Nick Tonelli]

That was voltage at the starter. The voltage at battery is 12.5 does not drop while turning key. Engine turns easily by hand

 

[Vetech63]

Internally corroded battery cable more than likely. Is the ground strap still attached to the frame and starter mount bolt?

 

[Delmer]

One step at a time, move to the cable terminal, then the other end, then the ground, then the other end of the ground. It's not hard to test, just takes some thought to isolate what you're testing for, in your mind.

 

[HarleyHappy]

11 volts at starter means a volt drop from battery to starter.
That drop is more than likely where you’re los that amperage you need to start. 8.4 while starting is not good. If cables are fine that would indicate a bad battery.

 

[melben]

Did you check the ground strap where it is bolted to the tractor, I have had many of those get hot and lose connection intermittently, a good test is a test light to a good ground then check the NEG post while trying to crank, a lit light will show current taking an alternate path to ground. A sure sign of an open ground circuit.

 

[Nick Tonelli]

Thank you for all the input it’s greatly appreciated. I haven’t had a moment to look at machine with two sick kids and work but I’ll be trying all of these to hopefully track down root cause

 

[Nick Tonelli]

It’s fixed! Thank you to all that chimed in. I initially hit the ground bolts with a wire brush and made sure they were secure (but never removed as there was little/no signs of corrosion). Because of my inexperience using a multimeter I was able to get continuity by placing my probe where the red line indicates. Not knowing better I figured that meant it was a good ground since it was also a nice clean tight connection. It wasn’t until after when I watched a video and the guy mentioned testing the LUG that I realized my mistake with the multimeter. I got no continuity when probing the lug so knew that was my problem. Something so simple but my multimeter diagnosis experience is lacking so it was good learning moment….

Removed bolt and the corrosion was obvious. Cleaned up area and replaced chassis ground strap as well as replaced those bolts. Thank you all again this forum is great

This is the video that lit the lightbulb in my head:

 

[edgephoto]

Anytime you have electrical issues you need to use voltage drop to find the bad connection. Measuring for continuity or resistance is nearly useless. Or check for voltage on a disconnected circuit.

I am a field engineer for a major auto manufacturer. Professional technicians who like to think they are in the top tier do not understand this simple test. Don't feel bad.

If you understand the math behind a voltage drop it will really make sense.

V=resistance x amps

For example in a starter circuit it can draw 800 amps or more. A 2 volt drop will cause slow cranking. To make things easy let's assume a 12 volts are applied to the starter. To lose 12 volts you use the formula:

Resistance(Ohms)=volts/amps

2 volts/800 amps= .0025 ohms.

Do you really think with DVOM you can measure .0025 ohms? This is why voltage drop is important.

 

[franklin2]

Anytime you have electrical issues you need to use voltage drop to find the bad connection. Measuring for continuity or resistance is nearly useless. Or check for voltage on a disconnected circuit.

I am a field engineer for a major auto manufacturer. Professional technicians who like to think they are in the top tier do not understand this simple test. Don't feel bad.

If you understand the math behind a voltage drop it will really make sense.

V=resistance x amps

For example in a starter circuit it can draw 800 amps or more. A 2 volt drop will cause slow cranking. To make things easy let's assume a 12 volts are applied to the starter. To lose 12 volts you use the formula:

Resistance(Ohms)=volts/amps

2 volts/800 amps= .0025 ohms.

Do you really think with DVOM you can measure .0025 ohms? This is why voltage drop is important.

The above is correct. A more detailed description of a voltage drop test is to test for voltage at different parts of the circuit while someone else is trying to start the engine. Poking around with the voltmeter with the system just sitting there will tell you nothing.

 

[edgephoto]

Exactly. You must test voltage drop in an operating circuit. With 5 measurements I had diagnosed my slow cranking to a bad solenoid. Removed the starter cleaned everything up and reassembled. She cranks fast and starts instantly.

I did the tests by myself. I have long test leads and alligator clips. If you do not have good test leads buy some. Probes are close to useless for tests like this. You need alligator clips.

Fluke makes the best test leads and meters. They do not give anything away and for the average shade tree mechanic they are too rich and overkill.

I am not sure of the quality but this looks like a decent alternative to the Fluke equivalent. Fluke Knock off leads