Nippondeso starters

Does anyone else have problems with Nippondenso starters on Kubota engines? I had my starter rebuilt a few years ago by a ND distributor with original parts. A couple month's later it clicks several times before turning, the reason I took it in. They said it was just worn out and it cost over $250 to rebuild it. Took the starter out and was going to take it back. Just on a whim took the end cap off the solenoid and could see the problem. The copper contact on the plunger and wiring contacts were all black from arcing. Cleaned them up with some sand paper and everything was good or so I thought. I've had to this a couple times and just did it again last weekend. Last year it seemed like it was turning a little slower so added an extra ground cable from the starter bolt to the frame. This helped and it spun at normal speed. Now the contacts were arcing again. Luckily I got the machine back in shop so I didn't have to fix it in the rain. Only took about 10 minutes but still annoying to have to do every 100 hours or so. Engine is a 43HP V1902B with dual 12 volt batteries for easier winter starting. Is this just a quirk with ND starters or is there a way to cure the problem?

Same issue with a 24V starter on a case dozer. I'm going to add a secondary relay and extra ground cable today to see if I can get this dam thing to live longer than 90 days. My rebuild guy says they are junk even when new, but no alternatives at the moment.

These starters are great, but the machine manufacturers scrimp on the wiring to activate the solenoid. It works great when the machine, (or even car) is new, but as soon as it ages, the resistance goes up just a little, and there is no extra capacity. What I do is just what Vetech is saying.

I take a ford style solenoid and put a 10 gauge wire from battery hot, either at the +post or the battery post on the starter, to one of the big posts on the solenoid. Another 10 gauge wire goes from the other big post to the start terminal on the starter. The original start wire from the switch goes to the "s" terminal on the ford solenoid.

I always pull the end cap off the solenoid and sand the contacts when I do this, unless it is a new starter.

I have probably done this at least 40 times over the last 34 years, and it has cured the problem everytime.

Early arc damage of the solenoid contacts is definitely a low voltage issue. When the voltage is insufficient, the current draw goes up. When the current draw goes up, the resistance of the wiring increases, which decreases the voltage.
Got that?

Now, as stated above, upgrade the power and ground cables. And, add a relay into the starter trigger wire circuit, if heavier (better) battery cables dont do the trick.

heymccall said:

Early arc damage of the solenoid contacts is definitely a low voltage issue. When the voltage is insufficient, the current draw goes up. When the current draw goes up, the resistance of the wiring increases, which decreases the voltage.
Got that?.

Click to expand...

Kind of a death spiral!

heymccall said:

Early arc damage of the solenoid contacts is definitely a low voltage issue. When the voltage is insufficient, the current draw goes up. When the current draw goes up, the resistance of the wiring increases, which decreases the voltage.
Got that?

Now, as stated above, upgrade the power and ground cables. And, add a relay into the starter trigger wire circuit, if heavier (better) battery cables dont do the trick.

Click to expand...

Need more detail LOL

Hey, Heymccall,
(just playing with your screen name. My brother was the shop foreman and later ops mgr for a 75 truck and a bunch of equipment outfit where I got my start and he had "Hey You" on the name tag on his uniforms)

You are dead on, but the problem is in the trigger circuit, not the battery cables. Those starters have a high amp draw in the pull in coil, thus when the wire degrades the resistance goes up, voltage goes down, then the coil doesn't pull the contacts together hard enough.

Thanks for all the help with this. I know it's a common problem. Starters work better in cold weather too. Shop because everything is contracted so easier to make contact.