Like I said, your battery is only an 80A battery, and just isn't enough to feed the Monster, and you risk burning up your Monster. I would wrather pay $65 for a new battery than have to pay $70-$150 for a new Monster and then wait forever and a day to get it.
Just go to
www.hobbycity.com and buy either a 30C 6S 5000mAh LiPo or a pair of 30C 3S 5000mAh LiPos (wired in series) and be done with it. Use EMS shipping and you will get it/them in 3-5 days.
Just my $0.02, because that battery just isn't enough, and will eventually destroy your MMM (unless you gear for 15mph and drive like a granny).