G6200HST starting problems (electrical)

[Johnny11]

Good morning all,

We've had a G6200 HST in our family since 1988, it has been at three houses and still going; remarkably only 600 engine hours.
One annoying issue that has been around for years is when tuning the key and the starter/motor barely turns [like a dead battery]. Once I realized that jump staring didn't help that much, I bolted an old battery cable to the solenoid and tapped the + side battery post, bypassing the internal wiring. The 6200 came back to life with this temporary fix.
I replaced the starter & battery back when it just wouldn't start (they both may have been fine).

Next in line for this tractor is my son, I can't have him tapping/sparking an old car battery. I know they are capable of (yikes).

Any others had these problems with the G series diesel tractors?

There are some bypass-connectors in the original dealer package, never knew what they were for.

Thanks!

John

 

[Dave_eng]

Start with the simple things.

The battery ground cable. The connection to the engine/frame needs to be removed and the metal surfaces polished bright.

Do any of your battery terminals look like this repair style?

To be certain I understand your temporary fix, look at this marked up photo and advise if this is what you are doing.

Do you have a manual which includes a wiring diagram?

Dave

 

[Johnny11]

Dave,

Thanks for the sketch.
So what I did years ago is use a 48" #8 wire (with a terminal) bolted it down over the stud/nut (with the existing top cable) and simply left the 48" cable the outside of the tractor.
To start the tractor, I tap the battery + to crank it up.
At the same time I turn the key, which seems to help with a quick start.

I'll look for the schematic, I think I saw it on line the other day.

 

[Johnny11]

Ugh...I'm wrong.

 

[Johnny11]

Looks like I bypassed the solenoid after all.
Which doesn't explain the slow cranking on a new starter.
I'll jump down to the black/yellow wire next.

 

[Johnny11]

I'm wrong again, low power at the black/yellow.
This is a 12v headlamp, it just glows a bit with the key turned.
Also, jumped the the solenoid + to the smaller terminal, it cranks right over.

 

[Russell King]

Look into cleaning all the terminals that are involved.

As you say not enough power to fire the solenoid.

Look at installation of a relay using the black/yellow as the firing wire on the relay. You can probably use the #8 wire as the incoming power of the relay. Out will connect to the solenoid where the black/yellow is now.

That should solve the problem. There are kits you can buy to use for the relay. I recall that John Deere has one.

 

[Mark_BX25D]

How about just replacing the cables on that old beast? They are probably all in need of it.

BestBoatWire.com

Choose your length, gauge, and terminal type. I like to get the clear heat shrink on the ends. That way you can see what's going on under there.

I have been very happy with the service and products from them.

 

[Johnny11]

Thank you both for the replies.
I did find two after market stater switches: Advance Auto (5 bucks) and a heavy 50 amp on Ebay (6 bucks).
But that said another clue, when tuning the key in either direction there is a buzzing like a relay is not working. The glow plug indicator is not at full power either.
Now if I can find that relay!!

 

[BruceP]

The 'buzzing' you are hearing is a TELLTALE symptom of poor connection somewhere.

Here is what happens:
1) Voltage starts out high enough to 'pick' the relay
2) The relay picks (putting more load on the circuit)
--this also causes voltage to drop due to resistance of poor connection (Ohms Law)
3) At this instant, the voltage is too low to keep the relay 'picked'
--this causes relay to release
[The above process happens many times per second.... in other words, the relay flaps back and forth at high speed causing a 'buzzing' sound]

To troubleshoot and isolate this problem, use a VOLTMETER connected such you are measuring VOLTAGE DROP. Less than 5 minutes of probing around will tell you EXACTLY where the voltage is being dropped due to high-resistance.

I have described how to do "voltage drop" measurements several times in other threads. With load on circuit, assume ANY measurement over 50mV (0.05v) is too high and there is poor connection. (The ideal wire would have 0.00000v dropped across it)

For example:
If you put one probe on engine-block and the other probe on battery-negative terminal (NOT THE CONNECTOR) Then try to crank engine. If voltage rises above 50mV, the wire from battery-negative -to- block has bad connection.

Repeat this test across every wire related to starting-system such as.....
(battery+ to large red wire on starter solenoid)
( battery+ to small wire on starter solenoid. )

 

[Johnny11]

Bruce,
Thanks, I'm digging into this a bit more. I see you have the G5200, I think they are mostly the same.
Popped off a cover and removed the battery to access the wiring.
It appears the key-switch is in the center of the these two low voltage problems: the glow plug heater/starter-solenoid.
I'd like to remove it and check it over but didn't get far with removing it, only the outer chrome ring.

Does anyone know how to remove the switch?

 

[Russell King]

It looks like you have it ready to remove already. Is it possible to move the black plastic dash up away from the switch? I don’t think you have enough room to get the wiring off the back of the switch while it is in place. I think the wires are screwed to the switch, not slide on terminals.

 

[Johnny11]

Yes so close to removing it, I just need to remove that ring, it will pull away and I can swap it out easily.

 

[Russell King]

I believe that you will have to unscrew the ring on top from the switch. Use a pair of channel lock pliers to grab the OD of the ring. I think I can see threads on the switch in your picture.

 

[cliffboyer]

No need to remove dash. Remove battery to access switch. A channel locks will work on the ring, but a spanner wrench is ideal. Alternatively screwdriver or punch with a few light taps of a hammer will do.

My switch has a dead spot on the solenoid contact. Its a sealed unit, so no repairing it. Replacing is on to-do list. I have been bypassing with push button on the solenoid terminal on starter.

 

[whitetiger]

Bruce,
Thanks, I'm digging into this a bit more. I see you have the G5200, I think they are mostly the same.
Popped off a cover and removed the battery to access the wiring.
It appears the key-switch is in the center of the these two low voltage problems: the glow plug heater/starter-solenoid.
I'd like to remove it and check it over but didn't get far with removing it, only the outer chrome ring.

Does anyone know how to remove the switch?

View attachment 51394 View attachment 51395

The white Teflon ring is what is left holding your switch in the dash, a putty knife or small screwdriver will pop it off. That white ring is "Tougher than boiled owl!!"

 

[Johnny11]

Thanks Whitetiger,

It might come to that,,, pulling the white ring off.
Ordered the switch today, lightweight compared to all the other massive parts on the machine.

btw, Electrical schematic was easy to find:

G3200 to G6200H operators manual.pdf - Kubotabooks.com

 

[BruceP]

Just FYI - My G5200 used to have some issues with starting. The starter-solenoid would 'click' but not engage the starter.

Long story short.... I determined that the two 'safety switches' (as seen in schematic in previous post) had resistance across them which was dropping the voltage. Hence, the voltage at the small terminal on starter-solenoid was insufficient when key was engaged.

I developed a PERMANENT fix for the problem by wiring in a a new relay. Now, the 'safety switches' only have to pick a small relay. This new relay is what supplies higher current which the starter-solenoid requires to work properly.

 

[Johnny11]

Parts are slow to get here lately.
But the switch came and installed that today.
No change at all, which wasn't totally unexpected.
I'll try running a jumper from "st" on the switch down to the starter.
(Black/white wire)

 

[Johnny11]

The switch didn't help, and ready to try another replacement part.
Can anyone tell me what this is?
[the GlowPlug indicator doesn't work either]

Thanks!