Ford Escort LX 1

Ford escort LX 1.9 Litre. Engine runs cold all the time. Before it ran normal with good heat and temp guage would go to about half way, Now it barely reaches 1 quarter of the way and won't put out that much heat when heater is turned on, before it put out so much heat that if you turned it on full it would blow you out of the car and now it puts out little heat when on full with fan on high. I replaced the thermostat with a 195 degree new one but still won't put out the heat like it use to, Everthings good on the car, I relaced the water pump last year, all hoses good no leaks anywhere and good 50/50 antifreez still the same thing. Starts up runs perfect but the temp guage won't go past 1 quater of the way and heater won't put out good heat like it use to, everything works correctly just loss of good heat. I let it run idle 20 minuts but it wouldn't get hot to even turn on the electric cooling fan. Good coolant flow it just wont build up enough heat. I can tell the thermostat is working because I drive it and the heat guage gets up to about 1 quater of the way and then drops back down to allmost starting temp and cycles. When this car was brand new the temp guage would go to just under half way and pretty much stay they good heat in winter and run perfect. I'm not an expert but have been fixing cars for 30 years and can't figure3 it out.