didn't use coach last year but now looking to get back on road. now have problem with coolant system. low water light comes on & overheats after driving for approx. 1hr. check coolant in radiator now low. also now have excessive blowby from crankcase breather. smoke is whitesh in color. checked oil no signs of water in oil[at least on dip stick]. no smoke in exhaust. because of motorhome age don't want to spend alot of money to repair.