This motor was laying on its side for about 2 days in the back of my truck, it's leaking gear oil after getting it mounted right side up from the hole in the picture? Guy I got the motor from said it probably leaked passed the upper shafts seal because of how it was laying. Seemed to have slower down after leaking about a 16th of a quart of gear oil...Obviously it's not normal so I'll keep an eye on it. But what is that hole normally for??