Kubota garden tractor starting issue

[KYKub]

I've been lurking and learning from many of you (thanks!) and am now writing my first post. While reasonably handy, I am anything but a mechanic.

I have a new to me Kubota G1900 4WS garden tractor. 917 hours and in great shape. 60" mower and 48" snow blade. When starting, it needs a boost unless it is warm from running recently. The engine turns over fairly quickly but it fails to fire; when I then connect my charger with a 300 amp boost option, it fires right up! I have replaced the battery with a good 500 cold cranking amp battery. I also cleaned the main ground connection at the frame.

I had the guys at Autozone test the battery, alternator, and starter. The test results indicated a good battery, a failed voltage regulator, and "starter current failed." Even though the voltage regulator "failed," the alternator was still producing 13.64 volts.

* I am really confused because even if the alternator was completely dead, that shouldn't affect the starting of the machine, should it? (With a fully charged battery.)

* When I gave it a boost it seemed to work better if I connected the hot lead directly to the solenoid.

* Why would adding a few more cranking amps from my charger make the starter turn faster?

Any advice or testing recommendations would be greatly appreciated! Jeff

 

[DT86]

Poor connection between solenoid and battery?

Jump from battery to solenoid and see if it starts.

 

[KYKub]

Hi DT86. Thanks for the message. I checked the connection between battery and solenoid and it is good. However, my brother (who has a good bit of diesel experience) figured it out, I believe. It turns out that the glow plugs were bad, two completely dead and one warming intermittently. Replaced the glow plugs and it's running like a champ! Still a little confused by the electrical system tests, but I'll wait and see if any problems occur.

Thanks again, DT86! Jeff

 

[jabr1319]

I have this same issue. How was the glow plug replacement process?

-Josh

 

[KYKub]

Hi Josh. Replacing the glow plugs was easy (and I'm not an experienced mechanic). Remove the top nuts, lift off the hot wire and plate that connects the three plugs, and then remove each glow plug. They're like skinny spark plugs.

I ordered replacement glow plugs from the local Autozone. Didn't stock them, but had them in two days. $63.00 for all three. NKG YE01 was the brand and part number.

After replacing the glow plugs it fires right up, even on cold mornings (cold by KY standards, probably not for you north-easterners).

I hope this is helpful. Jeff