520H No start

[GoBucks 4]

Since I bought this in April, I had one time when I went out and it wouldn't start, no turning over, just dead, but the battery etc was good. I looked around for awhile, didn't really do anything, and it just worked. It's been several months, and hasn't done that again until last week. I checked the battery again, looked for any loose wires, etc No luck. The gauges, test lights all come on.

 

How do I see if the starter is getting power? I saw the 2 big nuts, one has a wire, the other doesn't. There is also a small white push on type connector wire. Where do I check for 12Volts? Any other thoughts of possible suspect areas to check for a loose wire?

 

On a slightly related note, when I bought it, the headlights/taillights worked, by the time I trailered it home 3 hours, they didn't work, but everything else did,

 

Thanks,

Sam

[953 nut 55,391]

With any electrical problem the first step in correcting it is to clean and tighten all electrical connections. This will cure the majority of electrical problems, especially intermittent ones. 

 

[GoBucks 4]

FYI: I did take out all 3 fuses, and I could measure 12V across the fuse holders.

[EricF 589]

On 7/15/2017 at 3:03 PM, 953 nut said:

With any electrical problem the first step in correcting it is to clean and tighten all electrical connections. This will cure the majority of electrical problems, especially intermittent ones. 

 

Exactly. And that includes ground connections to the frame/engine. Bad grounds can really leave you chasing ghosts.

 

Also, watch out for the safety switches, like the seat switch and the neutral and parking brake switches. Check their wiring and connections. Stomp the brake pedal down a couple of times and then hold it down, while wiggling the motion lever to make sure it settles into neutral so both the safety switches should be set correctly.

[Duramax7man7 506]

Did this get fixed?

[GoBucks 4]

Not yet, the Previous Owner already disabled most or all of the safety switches, like the seat.

[Duramax7man7 506]

Have you pulled the ignition switch plug off and took a look at it. Could just be a loose connection there. 

 If you try and start the tractor, ground your multi-meter somewhere by the starter and then touch the positive terminal to the light blue wire on the starter. Then have someone try and turn over the engine. That's how you test the ignition wire for the starter. Which for a 1991+, will also tell you if you are getting power out of the Starter relay but only if you are getting power to the switch relay first which means all of the safety switches are disabled (and completing the ignition circuit). 

 Is yours older than 1991 or newer?

 

 For 1991-1997 520h scroll down to page 441 (7-97) -has 3 relays

 For 1990 520h scroll down to page 449 (7-105) -has 1 relay

 

Demystification Guide:

 

Edited July 21, 2017 by Mastiffman

[GoBucks 4]

1995 I believe, I'll give that a try. Thank you!

[Duramax7man7 506]

My 1991 520H was the start relay and the seat switch... I din't realize it being that the label for instrument panel lights was torn off. 

Edited July 21, 2017 by Mastiffman

[GoBucks 4]

Thanks for the link, that should help a lot!

[WVHillbilly520H 10,373]

The '95 I bought last spring had a jumper wire from the ignition switch to the starter removing it was a no start/turn over, after going over the harness twice if not more and wiring around the dreaded 9 pin molex to find the neutral safety switch under the dash was "good" (top pic) but had a broken actuator (replaced 2cd pic) and now the PTO switch is starting to act up,  the battery acid gets to corroding those microswitches and actuators so be sure to check all these and use dielectric grease after cleaning and tightening  connections, Jeff.

[GoBucks 4]

So, I took my meter, put it on a ground, disconnected the blue wire to the starter, turned the key and had 12 volts. So, that means all of the safety switches are good, and the wire. So does that mean it is the starter/solenoid for sure, or do I need to test something else?

[WVHillbilly520H 10,373]

Take a jumper wire from the battery + terminal directly to the solenoid, if it engages then the starter is ok but make sure the safety switches still have their actuators attached like my above post, it took me 3 weeks to figure out it was missing even looking right at it and testing with multi-meter, Jeff.

[lynnmor 7,319]

It could show 12 volts with poor connections and inadequate wiring.  Reconnect the blue wire and voltmeter and retest.  Now with a load on the wiring and the voltage is still near 12, it points to the solonoid or starter being bad.  Like Hillbilly said, jump from the battery to bypass all the wiring.

[Duramax7man7 506]

11 hours ago, GoBucks said:

So, I took my meter, put it on a ground, disconnected the blue wire to the starter, turned the key and had 12 volts. So, that means all of the safety switches are good, and the wire. So does that mean it is the starter/solenoid for sure, or do I need to test something else?

 

 

I have a question. Can you start the tractor right now without touching the starter from the ignition switch? If so, I think that you should try and troubleshoot that light blue wire when you can't get the engine to turn over. So if the engine doesn't turn over, check to see if the light blue wire is still reading around 12v. If you can't start it then do what they suggested above. 

[GoBucks 4]

Update...

 

I took my meter back out again, using a jumper to a ground. I tried to test the Blue wire still on the connector. No luck.

 

I pulled the blue wire off, tested, 12V good... I then tried to test the back side of the connector while it was still off. 12V, so I left my meter probe in the back side of the connector and pushed it onto the connector on the starter/solenoid. This is while I had my Left hand on the Ignition key to the Start position. Several times I tried and it seemed as soon as I touched the connector with the blue wire, I would lose the 12 Volts. However, while doing this, the Headlights/Taillights, suddenly came ON. They haven't been on since I bought it in April before trailering it 3 hours home.

 

What in the world does the blue starter wire have to do with the headlights?

 

Anyway, I continued on, I thought the starter was shorted and the load was killing it.

 

I decided to try Jump starting it as suggested. I found a good piece of solid wire of sufficient length. I left the blue wire/connector ON the starter, I then pushed the stripped end of the solid wire into the back side of the connector. I then touched the other end of the wire to the Positive Battery terminal. The starter kicked over. Ok, it must be the wire. I then took off the wire and turned the key, it turned over, started, headlights work. Everything seems great.

 

Any ideas? The Spade side of the connector on the Blue wire always tested 12 Volts, so it doesn't seem like a loose connection there. Possibly crud on the "Blade" side of that connector that is ON the starter?

 

Still surprised the headlights started working again.

 

How many Volts does your meter show when the tractor is running? Mine shows a solid 12 volts with my external meter, but the Meter ON the tractor looks more like 11 volts.

 

Also, I believe the previous owner replaced the stock battery with a Car battery, it's not a typical lawn and garden one like on the 416-8 I had/have that isn't running.

 

Thanks for the help, 3 weeks of cutting grass with the push mower is OVER!

[953 nut 55,391]

3 hours ago, GoBucks said:

How many Volts does your meter show when the tractor is running? Mine shows a solid 12 volts with my external meter, but the Meter ON the tractor looks more like 11 volts.

Be sure the 30 Amp fuse is good and the fuse holder is good, the charging circuit passes through it.

3 hours ago, GoBucks said:

Possibly crud on the "Blade" side of that connector that is ON

In the long run you will save yourself a lot of aggravation and down time (pushing the old push mower) if you will take the time now to clean and tighten all of the connections including grounds.

[lynnmor 7,319]

I do believe that you have a very bad connection somewhere.  Check grounds as well.

 

With the engine running faster than idle, the voltage should be well over 13 volts.  Let it run a few minutes while checking.  The size of the battery doesn't matter, it will just take longer to get fully charged.  A fully charged battery should read about 12.8 volts with nothing turned on.  If you have a good battery charger, bring it up to full charge and always keep it fully charged for longest life.

[WVHillbilly520H 10,373]

The light blue wire as in my pics above go to the neutral safety switch and starter relay, the dark blue is oil pressure, according to the 1995 manual Jeff.

[Sarge 3,463]

Never assume battery cables and other connections are sound at the terminal - it's quite common for moisture to get inside the crimped area and rot the copper wire out , which will lead to a serious drop in voltage/amps . First thing I do with a new acquisition is to make new battery cables that are fully crimped/soldered/sealed with high quality solid copper ends . It eliminates headaches later and helps keep them reliable . The 520 and it's wiring issues is all down to connections that are far too light to carry the load and low-quality connectors , which is not uncommon . Due to the number of safety switches and gauges , it just makes the whole thing more complicated but by breaking down the various circuits it can be repaired . I fixed a lot of the connections in one of these a guy in town had years before owning my first Horse - that tractor was less than 3yrs old and already had wiring issues from hard use . The folks here more familiar with them have the knowledge you need and sure are a great asset to our forum....would love to own a 520HC one of these days myself .

 

Sarge

[Duramax7man7 506]

I 100% Agree. I have found that taking the time on new acquisitions to clean up the steering tower grounds is the best first step to correcting any wiring issues. This will automatically alleviate any thought to bad grounds. Then look at harness to engine harness connections, then take a little time to clean up with a dremel and a fine grit sanding disc, all of the male connections and tighten the female connections back up with some needle nose pliers as well as repair any broken or rubbed bare wires and cut out the corroded stuff while at it. Lastly, make sure the battery cables are replaced, repaired or at minimum, cleaned and tightened up from battery to starter to the frame. This will help hunting down the issue much easier.