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Radiator hoses and thermostat

How can you tell if your radiator hoses or thermostat are bad? everything inside car seems fine…temperature gauge is in center and all cooling systems seem fine.

honda 2002/104,000 miles

Thermostats when they go bad usually stick in the “open” position. This means the car is slow to come up to temperature and might not ever reach the center normal place on the temp guage. It is possible to stick in the “closed” position, which would cause the motor to overheat. It sounds like your thermostat is fine. In a 2002 you could replace it as a precaution, but be sure to put in the same temp thermostat if you do. I’d leave it alone.

The radiator hoses on Honda’s are generally good quality from the factory. When the car is warm you can do a simple “squeeze” test and you are looking for soft spots. Pay particular attention to the places where the hose connects to the radiator and/or motor. Also pay attention to the areas where hose has any sharp bends. The hoses on my '03 Civic with 97K miles are still in good shape.

If you opt to replace the hoses make sure to get good quality pre-shaped hoses. Cheap replacement hoses don’t last nearly as long as the originals that Honda puts on at the factory. These are the hoses with “ripples” in them so they can be bent into lots of shapes. They are fine for emergency replacements, and last for a few years but not as long as the pre-shaped ones.

Thank you…I am new to cars but what should a soft spot feel like? what does a good hose feel like? I think I will leave thermostat alone…i think dealer was trying to make suggestive repairs but said car is runnning fine…i guess female=sucker;)

Hoses in good condition feel hard when you try to squeeze them, hot or cold. Worn hoses feel somewhat squishy when you try that.

Having a rad hose blow on an expressway is no picnic. It happenmed to me once and the coolant will blow all over the windshield if it is an upper hose. Most hoses now are good for close to 100,000 miles. In any case 10 years is about the safe maximum for rubber parts.

Belts can snap without warning when they get old. Even if they look good. I drove a relative’s car across the country in late Novemer. When I started the car on a cold morning in the Mid West, the fan belt just snapped. These belts were the original and were 12 years old! Again, I would replace any belt 10 years or older.

I’m not sure the dealer see’s “sucker” on your forehead. A new thermostat and hoses isn’t a bad idea for someone who really doesn’t want to have a problem on the road.

Feel the upper hose running from the radiator to the motor. It is exposed and you can feel most of it. You are just felling for a “spot” that feels softer, or easier to squish, than the other areas along the hose. A soft spot indicates the hose maybe coming apart from the inside out and hence the softer area. This is not a fool proof test, but it can help find a bad hose.

The bottom hose is hard to get to unless you get under the car and reach up. Heater hoses are smaller diameter hoses that you’ll see disappear into the inside of the car at the back of the motor on the passenger side. There are AC hoses running into the inside of the car in the same general area.