Battery dying or belt slipping?

[auraaura]

I've got a ym3000. About every 3rd or 4th time I try to start it- it won't really turn over. Like the battery is dead. Even after engine is warmed up. I can switch it off and try again and so far has always started on up. My belt is loose and can't be tightened any more. Could it be slipping enough to be not charging the battery? Wouldn't the engine be running hot if it was slipping that much (it's not)? I've got a new belt but so far have been too lazy to put it on . Battery voltage reads 12.9 when engine is running. Should that be higher? Whaddya think? Put on that new belt, get a new battery or both? Much obliged!!

 

[LouNY]

Should be closer to 14.4 volts when running, replace the belt and may be fine.

 

[FordnMassey]

Hi,

I'm with LouNY. I've had this happen on a Massey Ferguson 35 petrol/gasoline. I thought the battery was dying, but tightening the belt resolved the issue. No issue with over heating.

I also had to buy a shorter belt.

 

[bmaverick]

I've got a ym3000. About every 3rd or 4th time I try to start it- it won't really turn over. Like the battery is dead. Even after engine is warmed up. I can switch it off and try again and so far has always started on up. My belt is loose and can't be tightened any more. Could it be slipping enough to be not charging the battery? Wouldn't the engine be running hot if it was slipping that much (it's not)? I've got a new belt but so far have been too lazy to put it on . Battery voltage reads 12.9 when engine is running. Should that be higher? Whaddya think? Put on that new belt, get a new battery or both? Much obliged!!

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[5030]

12.9 is basically dead. Replace the belt and buy a new battery too. It's probably old and shot. Batteries don't last forever (neither do belts) for that matter.

 

[bmaverick]

12.9 is basically dead. Replace the belt and buy a new battery too. It's probably old and shot. Batteries don't last forever (neither do belts) for that matter.

Mine keeps at 12.5VDC since 2014. It's only been an issue when it dropped to 11.2VDC when the altenator died. I trickle charged it for a year before swapping in a new alternator and VR. It's still keeps at 12.5VDC to this day. The YM2610 starts right up too.

 

[auraaura]

Thanks for the advise folks! It's a rainy day in mississippi and I've got a shop I can put my tractor in. Belt changing today, woohoo! I'll post back my resluts.

 

[5030]

Some folks get a long life out of flooded jars, some don't. Depends on the situation and use. In my case living up north in the cold, they don't last a long time and my SOP is every 5 years they get changed out. I never trickle charge them either but I do take them out of circuit with an isolater when not in use and of course my alternator belt is tight and the terminals are clean and bright as well on the jar as well as the rest of the charging connections. Corroded terminals and connection points will kill a system real quick and batteries are often times neglected until they fail.

 

[ponytug]

Mine keeps at 12.5VDC since 2014. It's only been an issue when it dropped to 11.2VDC when the altenator died. I trickle charged it for a year before swapping in a new alternator and VR. It's still keeps at 12.5VDC to this day. The YM2610 starts right up too.

I'm glad that 12.5V works for your tractor, but if it is an accurate voltage, that isn't using the full capacity of your battery. At rest, 12.5V is around 70% capacity.

From: https://www.scubaengineer.com/documents/lead_acid_battery_charging_graphs.pdf
(Which has other great graphs)
Normally, a lead acid battery ought to be charging at closer to 13.8V.

I'm generally of the "if it ain't broke, don't fix it" belief, but I do wonder if it is possible that your volt meter might be out of calibration.

All the best,

Peter

 

[bmaverick]

I'm glad that 12.5V works for your tractor, but if it is an accurate voltage, that isn't using the full capacity of your battery. At rest, 12.5V is around 70% capacity.
View attachment 791002

From: https://www.scubaengineer.com/documents/lead_acid_battery_charging_graphs.pdf
(Which has other great graphs)
Normally, a lead acid battery ought to be charging at closer to 13.8V.

I'm generally of the "if it ain't broke, don't fix it" belief, but I do wonder if it is possible that your volt meter might be out of calibration.

All the best,

Peter

There is a huge swing of 12.5 vs 12.6 vs 12.7 at rest. Like you said, not broken, don't fix it.

Not bad for a 9 year old battery way up north here. It's a group-31, so it's massive size and deep CCA gives it the advantage too.