99 Mercedes C220 CDI temperature rise

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Fri 3 Aug 2007 18:16
99 Mercedes C220 CDI temperature rise - briang
Hi,

Just recently my 1999 Mercedes C220 CDi temperature gauge has started to rise higher than it has before I have checked the electric fan and that seems to be running OK but the gauge still rises above the normal centre position, It hasn't boiled over its just that its worried me when I'm in traffic as soon as the road clears the gauge goes back to normal or sometimes slightly lower than normal.

The antifreeze/coolant hasn't been changed for 2.5 years would that make any difference, and has the fan got 2 speeds as while it is turning quiet fast and you can't see the fan blades it really doesn't seem be steaming it around, I have said that because on an old car I had years ago the electric fan really used to make a lot of noise when it was going and the Mercedes one doesn't Is That Normal

I would appreciate any suggestion, it could just be me ??

THANKS

BrianG

Slight tweak to subject line - PU
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Fri 3 Aug 2007 20:10
Mercedes C220 CDI temperature - jc2
Radiator is probably getting a little "furred" up but as long as you're not boiling.
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Fri 3 Aug 2007 21:36
99 Mercedes C220 CDI temperature rise - John S
If the coolant has been changed once or so since 1999, it shouldn't be furred up, as modern antifreeze is good for 5 years or so. Could just be a combination of the warmer weather and perhaps a lazy thermostat. It seems thay can go slightly awry and not fail completely. I've noticed on my Astra that for the last couple of years it has run a few degres cooler than normal, only reaching its 'old' temperature in warm weather. Could be more serious, so do keep an eye on it.
JS
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Fri 3 Aug 2007 21:54
99 Mercedes C220 CDI temperature rise - jc2
Even with regular changes of anti-freeze,cooling efficiency will drop.
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Fri 3 Aug 2007 22:29
99 Mercedes C220 CDI temperature rise - Aprilia
Merc of this vintage would be on a two-year coolant change cycle.

In my experience MB thermostats can get a bit 'lazy' - might be worth changing it. Hard to say if there is even a problem without seeing the car personally.
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Fri 3 Aug 2007 23:13
99 Mercedes C220 CDI temperature rise - John S
Cooling systems have significant capacity to deal with extremes of climate. They need to be very degraded to allow overheating. The OP notes that the car sometimes runs a little cool which is why I suspect the thermostat.

JS
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Sat 4 Aug 2007 09:29
99 Mercedes C220 CDI temperature rise - jc2
Most manufacturers fit different heater and radiator packages dependent on the market-for example,a Northern Europe package and a Southern Europe and other specs to cover the rest of the world.UK would normally be fitted with a Northern Europe package.
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Sat 4 Aug 2007 10:09
99 Mercedes C220 CDI temperature rise - briang
Hi, Everyone

Thanks for your suggestions I think I will replace the thermostat and watch what happens for a while

Thanks again

Brian
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