There is either a tach cable coming from the engine or the hour meter is wired into the dash componant. If the RPM meter still work and gives you the RPMs then you need to spend about $300 to repace the dash. If you don't want to spend the money then go to Northern tools and buy a $30.00 1" x 2" square electric hour meter. To install, cut a small square hole in the plastic about 6" under the steering wheel after you take off the plastic. Install the meter with the wires going to the ground and the other to the hot side of the ignition switch with the key on. This should give you a cheap and reliable way to keep track of the hours.