520-H engine temperature light

[mlh163 0]

early 90's onan 20 hp engine temp light comes on after about 20 minutes. i try to keep screens clear and engine fins blown out light still comes on . any ideas

[Bow_Extreme 580]

Have you recently removed the engine covers all together and cleaned out the cooling fins? This is very important to do, especially to the rear side of the engine. The only way to get them all clean is to remove these covers!! Also, is there a grommet around the oil filter? I've seen many that don't run this grommet and they should to allow air to properly flow thru the engine. What kind of oil are you currently running? What exactly are you doing with this tractor for 20 minutes or so? Mowing? There is a large breather hose that protrudes from the flywheel housing into the air cleaner assembly. Is this hose clear? When did you last replace your air filter and pre-cleaner? Have you recently traced down your wiring for your temp sensor. It could be you are getting a faulty reading. Is your PTO clutch adjusted properly? I know these are all little things but they are all important.