I need a switch for an 18v dewalt grinder ,the older model, the push up battery and not the slide on battery?

SOURCE: i HAVE A DEWALT DC729 18V DRILL

is this a north american model.all i can find is model DC727 & DC728 model. charger model 9116 & battery is DC9096 may work.charger volts 110v ac. if your buying the individual part like batt & chgr its more expensive than buying the whole kit is cheaper. hope i answer your question

SOURCE: My Dewalt 7.2-18v charger model #dw9116 is giving

It means there is too high or too low a voltage coming into the charger. Check your chord.

I had the exact same problem. After using the necessary security bit to crack mine open, I found that the large capacitor inside had come loose and needed to be re-soldered.

That fixed my charger.

SOURCE: dewalt 18v nicd battery not holding any charge!

Hello
You can revive the dead nicd batteries in your tools.
There is a simple guide that can fix all nicd batteries in few minutes, available here.
Thanks

SOURCE: Holding battery charge on 12v DeWalt batteries

Are batteries for the dewalt cordless drill interchangeable? Will an 18 volt battery fit in a 12 volt drill?

SOURCE: broken dewalt battery 18v lithium ion

When a Dewalt charger is showing a fast blinking red light it means the battery is no longer chargeable. It may be because of a bad cell or short inside the battery. Whatever the reason the charger will not charge the battery and it needs to be replaced.