Positive ground on ym2000?

[dgizmo1]

Just picked up my new toy a YM 2000. Left the key on last night and of course battery died. Was jumping off today when i realized it had a positive ground. It starts and runs fine, but i thought these had a neg ground. None of the lights work on it, can somebody tell me if this is right. By the way it is one of the red ones

[careyo63]

This should help.

[dgizmo1]

Thanks for the quick response, but already found that diagram, but still does not give polarity of battery

[California]

Negative ground.

[dgizmo1]

Thanks again for the quick response, but doesn't that mean it is cranking backwards? So if it is cranking backwards due to polarity being backwards that means it should be running backwards. Now i could be wrong (and won't be the first time) but as far as i know a 4 cycle engine can not ryn backwards

[California]

No, it can't run backward. For one thing the fuel injection is ~ 20 degrees before the piston gets to the top, so 40 degrees later than that would run terrible if you could start it at all.

Could the battery have been charged backward? I think that is possible.

Have you used a meter to verify the labelling on the battery?

As for your bulbs- Oil and Charge should light with key on and engine off. Temp can only be tested by lifting the wire off the sensor up front, and sticking a grounded wire into that wire's connector.

[Neat 1500]

Yes it is possible to have a reverse polarity battery, the lights still should work either way. if it is indeed backwards the regulator will be stuffed. a multimeter will confirm this.

[Neat 1500]

Could the battery have been charged backward? I think that is possible.

Yes it is possible, if fully discharged till it seems completely dead a reverse charge can be done but apparently it takes a hefty charger to get it started. i have never tried it myself but a friend has and it works.

[deepNdirt]

Yes a battery can be re-charged backwards once it has been completely drained of any power just as California and Neat has mentioned, Back this summer I purchased a used but supposedly " reconditioned battery " once I got it home and installed into my Roper tractor and one turn of the switch would sent the starter spinning but would not throw into the flywheel, When shorting the solenoid in attempt to start it only result in blowing the fuse,
I then hooked up my charger / Jumper to try and get stronger current and sparks flew as though I had wrongly connect the jumper.... I then brought the issue here to the YM of TBN explaining what has happened and was also suggest to check the battery polarity, It turned out to be Black was Pos+ and Red was Neg-, I connect the battery this way and resolved the issue, But rather than trying to drain the battery again and recharge it the correct way, I simply shaved off the protruding + & - and changed markings by carving them back into the right side so not to be confused again, ......... As far as I know any connection from a ( Grounded side ) of a battery to the chassis/ metal frame would be considered a negative ground, Not sure I know what a Positive ground is. Positive contact Yes! Positive ground No!

[deepNdirt]

This Positive ground talk had me curious, so I looked it up on Google, and found that yes there was a positive ground system
used on the Old 6-volt systems,.. in fact a positive ground systems has been dated to back in the 1920's..... which explains why I never heard of it I ain't that old