Ym276d not starting

[kempryan28]

Howdy gents,

I’ve been having a problem with my ym276d starting up. When I turn the key it is very inconsistent on whether or not it fires the starter. If I hook it up to my battery charger and set it to “jump” mode then it will typically start just fine.

I checked the battery first by taking it in to have it tested at an auto shop. They said it was all good to go. So not that.

Next I thought maybe the starter, so I ordered a new starter and put it on the tractor with the same problem occurring. So I sent it back and put the old one back on (after I took it after and inspected brushes and cleaned it out as well).

I have read many different threads on this and have found that putting a volt meter on it and testing if it’s getting its required 9v to the starter to make it turn. With ignition off it is getting 12.7v when my wife would turn the key to try and start it the volts would drop to 4v. I did notice that if she held the key to start the volts would climb and eventually fire the starter (it did this once or twice).

I replaced the ignition switch last summer, that didn’t seem to matter. Same problems occurring.

I bypassed the clutch safety switch to rule that out and I’m still having the issue. I see on my electric schematic that it also has a pro safety switch I have not yet located that to attempt to bypass it as well. However I do ensure the pto is in neutral when attempting to start.

I’m lost on where to look next. I’m certainly not an electrical genius. Ie I have a volt meter and get lucky every once in a while and use it correctly but beyond that I’m lost.

Any ideas on where to go from here?

As always any help is appreciated.

Thanks,
Ryan

 

[kempryan28]

Electric system schematic for reference

Also of note I forgot to take pictures of it but the pin connectors out of the voltage regulator had appeared to get very hot at times and nearly fused one of the wires perhaps causing a short. I replaced the regulator with one I had laying around add wire nutted the wires together until I can replace the pin connector. This didn’t fix anything either but it did appear to get hot out of the regulator at some point enough to damage that pin connector.

 

[Racer4]

Check all your battery connections at both ends of each battery cable. Take them off and wire brush them and reinstall.

 

[kempryan28]

Check all your battery connections at both ends of each battery cable. Take them off and wire brush them and reinstall.

Thanks I did try this although I will admit I didn’t get them as clean as I could (my wife brush wouldn’t fit in all the nooks of my cable ends) but I got em about 90% there.

I’ll bring the right brushes up next time I’m at the property and get em good and clean.

Thanks

 

[ponytug]

Thanks I did try this although I will admit I didn’t get them as clean as I could (my wife brush wouldn’t fit in all the nooks of my cable ends) but I got em about 90% there.

I’ll bring the right brushes up next time I’m at the property and get em good and clean.

Thanks

@kempryan28 When you jumped the battery with your charger, where did you connect the charger cables? Can you wiggle the battery post at all? It almost sounds as if you have a loose connection in the battery.

Don't forget to check that the wires going into the battery connectors are ok, too, i.e. they haven't corroded inside the cable or the clamp, or mostly broken due to vibration and arcing. To me, the 4V voltage says that you have a bad connection within the wire, or within the battery itself or a bad wire, or a bad ground connection. It seems as if when you are jumping the battery, you are either knocking a wire/clamp into a good contact, or bypassing the battery.

BTW, where are located?

All the best,

Peter

 

[kempryan28]

@kempryan28 When you jumped the battery with your charger, where did you connect the charger cables? Can you wiggle the battery post at all? It almost sounds as if you have a loose connection in the battery.

Don't forget to check that the wires going into the battery connectors are ok, too, i.e. they haven't corroded inside the cable or the clamp, or mostly broken due to vibration and arcing. To me, the 4V voltage says that you have a bad connection within the wire, or within the battery itself or a bad wire, or a bad ground connection. It seems as if when you are jumping the battery, you are either knocking a wire/clamp into a good contact, or bypassing the battery.

BTW, where are located?

All the best,

Peter

Howdy Peter,

I connect the cables to the positive and negative terminal on the battery over the top of the cable clamps.

I don’t believe the posts wiggle. If memory serves me correctly they are solid when I hook up to them but I will check next time I’m at the tractor.

I can check out the cables when I take them off at both ends and clean them with the brush per racer4’s suggestion as well.

I’m suspicious as well of just bypassing the battery when I jump it as I clamp onto the top of the cable clamps. I’m curious if when I took the battery to a shop if they testing it under load as well. Is that standard testing for a parts store test?

Thanks

 

[ponytug]

Howdy Peter,

I connect the cables to the positive and negative terminal on the battery over the top of the cable clamps.

I don’t believe the posts wiggle. If memory serves me correctly they are solid when I hook up to them but I will check next time I’m at the tractor.

I can check out the cables when I take them off at both ends and clean them with the brush per racer4’s suggestion as well.

I’m suspicious as well of just bypassing the battery when I jump it as I clamp onto the top of the cable clamps. I’m curious if when I took the battery to a shop if they testing it under load as well. Is that standard testing for a parts store test?

Thanks

Given that clamping the charger on the battery posts works, I think that taking a battery to a parts store to be tested on a load tester is the thing to do at this point. Good luck!

All the best,

Peter

 

[rScotty]

Given that clamping the charger on the battery posts works, I think that taking a battery to a parts store to be tested on a load tester is the thing to do at this point. Good luck!

All the best,

Peter

Sounds like the battery needs replacing. The auto store guy doesn't know what he's doing.

It takes time and a load tester to check a battery for the ability to provide a lot of current needed for starting. There are testing shortcuts. but they still take a full work day or more. Optima battery company requires a 12 hour load test for warranty claims. I think that's excessive, but on the right track.

Try this: take the cables off the battery and charge it at some moderate rate for overnight.
Then disconnect the charger, let the battery just sit there disconnected for an hour and then measure the battery voltage. It should be in the 12.7 to 13 volt range.

Now just leave it there still disconnected and let it sit for at least overnight or better yet for a day. Then measure the voltage again. It will drop some...but not much. Maybe 0.2 volts is typical for an older battery. New ones drop little if any. .... So if it was reading 12.7 after charging and sitting that hour, it should still be above 12.5 after sitting a day.

If it dropped down to 12.4 or below after 12 to 24 hours, the battery is not reliable for starting. It's still good as a 12 volt source for lights and such, but not for starting
luck,
rScotty

BTW, congrats on the starter brush rebuild. Nice to see someone doing it, Be sure to lightly sand the commutator and remove any carbon between the commutations.
And take the solenoid apart and clean those big contacts inside. That is often the problem with starting.
In order, troubleshooting goes: CABLES, BATTERY, SOLENOID, IGNITION. SWITCH, STARTER MOTOR.

 

[pycoed]

Thanks I did try this although I will admit I didn’t get them as clean as I could (my wife brush wouldn’t fit in all the nooks of my cable ends) but I got em about 90% there.

I’ll bring the right brushes up next time I’m at the property and get em good and clean.

Thanks

Try a jumper wire from the + battery terminal to the solenoid terminal on the starter. If the starter spins reliably, then the solenoid is OK, if not replace.
Also, if the tractor lives in the weather or in an open shed then it's possible that the main battery/starter cables have corroded inside their terminals. Try connecting the battery to the starter with known good jumper cables & see if there's a difference. I have a Cushman Truckster (Kubota engine) that lives in an open shed that had this problem which drove me nuts for ages!

 

[careyo63]

If the Battery connections on the cables have been replaced I've seen lose/Dirty connections on them countless of times. That shop can test or should test the CCA. or Amps. that you can't with just a V-meter. Amps=Volts. Which I use the highest CCA battery that would fit in the tray. 850 from Walmart. I used a 550 for Yrs. and was glad to finally see it go in the trash!! Charged it up before use all the time.