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Bad engine thermostat... long term effects? S70

Hello All

The engine thermostat on my 98 S70 is going bad. I have 136000 miles.

I know because this is the exact same symptoms my other cars had when theirs started to fail.

The temp gauge does not go up as quickly. Usually within 1 to 2 minutes of regular driving i have the temp needle at normal operating level. But now it is taking a lot longer.

Anyways, what are the implications of leaving the thermostat like this? Any possible damage to the engine? I am due for the 140K T Belt service when i plan on changin the water pump as well.

So does anyone know what damange if any i can cause by not changing the thermostat right away?








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    Bad engine thermostat... long term effects? S70

    On my (2) 850's and on current S70 all of the tstats have failed in the open position. I've not known one to fail in the closed position. With the tstat stuck open the motor is slow to warm and over cools when coasting down long hills. When I see the temperature guage reacting in this way I schedule the tstat replacement pretty soon after. I've not heard of any damage to car's systems by running in this overcooled condition, but I am aware that the fuel system tries to compensate for the cooler running engine by adding more/ritcher mix.

    The tstat replacement is not all that expensive, even at the dealer.

    good luck with this matter,
    Clive
    San Diego








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      Bad engine thermostat... long term effects? S70

      http://www.foreigncarpartsonline.com/


      A tsta costs roughly $15-19.

      A very easy for even "inexperienced shade tree" mechanic.

      See more at www.volvospeed.com

      cn








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    Bad engine thermostat... long term effects? S70

    No permanent damage to the engine as long as you keep an eye on the needle and watch for overheating. With a failing t-stat the engine won't reach max operating temp and your gas mileage will drop.

    Why don't you change the water pump and tsat at the same time, before the cold winter sets in and you wish you had changed them in warm weather.
    --
    '88 240, '92 745, '98 v70 John, Tampa Bay








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      Bad engine thermostat... long term effects? S70

      While in there, you should swap your ECT (sp?) sensor as well. That thing looks messed up after 40-60k's.







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