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Why is my honda running hot?

I bought a 1986 honda civic wagon and the cooling fan was wired to a hot fuse so it would run constantly. Would this have anything to do with my car running hot? It can be sitting in neutral and idling for 30 minutes and does not run hot until I drive it for a few blocks. Then the needle spikes to the hot line.

I wonder about the condition of your radiator. Are you sure the hot water from the engine is circulating through the radiator? When the motor is hot and the guage up near the red the radiator should feel very hot. If it isn’t you have a circulation problem, bad water pump, stuck thermostat, or clogged radiator.

I would guess a prior owner wired it that way because it was overheating for him. It did not fixe it so rather than fixing it, he sold it.

There are many possibilities, but I would start by checking the thermostat and then the flow through the radiator and I would be on the look out for exhaust gasses in the coolant.

Good Luck