I have a 1997 Ford newholland 8560 tractor. the other day my son was going to pull a friend out and this tractor still had summer fuel as it was minus 10F out the tractor started right up with the use of the glow plugs but. was not running right. I told him to park it at the shop and don't use it. a day later thought I should check this tractor out. it spun over but wouldn't start. I run the batteries down so thought I should put trickle charger on. I in advert hooked up backward for just a second the charge wrong, than changed it to the correct battery terminals. now the tractor will not even turn over it's like your trying to start it without pushing the clutch in. I checked all fuses everything looks good, I checked for fuses in line but could not find any. Ignition relay in the fuse box I have it on order from the local dealer, but had this relay apart and it looks good not burnt or any thing. doesn't smell burnt either.