I have a frined who is pregnant, with young kidsand no money. I'm trying to help her out, but have not worked on cars in a while. She has a 95'Blazer that is "overheating". The Fan is not electrical, although it turnsby hand, so it must be some sort of clutch. The fan even runs when started from cold (always runs). It appears as if the Water Pump never opens up because the Radiator and hoses stay cold even as the temp starts to red line and I don't feel any water flow.Thanks for any help!!

 

Now that I think of it, my fan turns when started too.

 

Thermostat?


just a guess...

 

The fan clutch is temperature dependant. When cold, it has a low resistance. Once the air temp through the radiator increases, it begins to lock up. This type of operation reduces the load on the engine from the fan when the radiator temp doesn't require high airflow.

I would recommend a coolant flush and refill with a new thermostat and a new slant radiator cap. Should be able to complete the job for under $40 if all goes well. Flush with regular tap water, but before you refill everything, flush 2-3gallons of distilled water through the system, making sure to forward and reverse flush the heater core (two hoses that run into the fire wall). Drain everything again and hook all of the hoses back up. Pour in approximately 1.5 gallons (1/2 the cooling system capacity) of fresh, new coolant. Then top the system off with distilled water. Run it up to operating temperature with the radiator cap off and add distilled water as necessary. With the remaining 1/2 gallon of coolant, top the bottle off with distilled water and mark as 50/50 mix. Over the course of the next week or so (depending on driving), check the coolant level periodically when cold.

So parts: 1 Slant safety release radiator cap, 1 Slant super-stat 195F, 2 gallons of Prestone All Makes, All Models Yellow extended life antifreeze, & 4-5 gallons of distilled water.

The Prestone antifreeze is compatible with the factory fill of Dexcool that the vehicle may already have. The water flush should get most of the current coolant out, but just as a safe guard, it's better to use a coolant that is compatible.

Good luck and let us know if you need any more help!

 

When the engine is hot is the thermostat housing hot to the touch? Are both the upper and lower rad hoses cold?
It probably is a thermostat stuck closed as it is rare that the water pump impeller fails. The most common problem with a water pump is for it to leak.

 

Hey Kyle,

Aren't you meaning STANT radiator caps, etc...

 

Yeah, I realized I typed it wrong each and every time after I submitted it, but didn't feel like changing it. LOL I'm tired, leave me alone!! lmao.

 

Thanks for all the replies!!!!

Distilled Water Flush, Thermostat, and Cap...

Flush and Cap are easy, just have to figure out where the Thermostat is now...

Thanks again.

 

Your thermostat is under the housing at the engine end of your upper radiator hose


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