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Do we need to change that Long Life Coolant anyway?

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 #254799  by boriquatwin
 
My 2002 300M (non special) radiator fan is going on more than usual. I've had the car for a year and i have put 30K miles on it already. It now has a 100k miles and i've changed the timing belt and water pump but I never did a flush. Do you think old water coolant is causing the fan to run? It doesn't over heat though I have noticed the the temperature needle is above the normal but never passes the half way mark. Above normal to me is under the half way mark. Is this normal? I've never heard my fan go off this much. Any suggestions on what to do? Should I change the thermostat? There is a Check Engine Ligh on but it's for a O2 sensor.

Thanks for your help guys!
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 #254804  by krautmaster
 
Fix the O2 sensor problem-it could be causing the engine to run lean, which makes it run hot....1/2 or less on the temp gauge is okay, but the fan shouldn't be on all the time.
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 #254814  by grayslater
 
Regardless if you "flushed" or not :) the question is, did you at least drain all the coolant (approx. 80% by volume)? Did you replace the upper & lower radiator hoses? If not do yourself a favor and replace them, the coolant with Zerex G-05 (or dealer equivalent HOAT), along with the thermostat. Highly recommended to test the thermostat in a pan of boiling water first to check the functionality.

Fans can be on much of the time in city stop and go traffic when the car is already at operating temperature.
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 #254939  by boriquatwin
 
Well I did the timing belt and water pump at 100k but don't know if the mechanic ever drained the coolant. I am hoping and assuming he did but I may just drain and flush myself since I think it's about that time. Also I am putting in a new thermostat. I've read to put the after market stat backwards unless I get an OEM. Is this accurate? Do you think a flush and thermostat change would be a good start for things?
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 #254942  by krautmaster
 
The spring end goes in the block-don't put a stat in backwards unless you want to turn your engine into a teapot... look for a Gates t-stat, I've always had much better luck with them than the Stant ones you find at the local parts stores.
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 #254962  by Bill Putney
 
Correct. regardless of which type you get, spring goes into the block. There've been reports that they come from the facotry the other way - maybe the original t-stat is designed totally differently? But - yeah - FSM consistently shows to install them the way Rich said, and people have proven that the other way doesn't work.
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 #254964  by boriquatwin
 
Thanks for your input guys. Getting brakes, coolant flush and thermostat change this weekend. Hopefully it will cool the engine off a bit. As I stated before it is NOT overheating but it seems like it doesn't take much for the fan to come on. It hasn't done this in the past.
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 #254973  by grayslater
 
I've replaced two original thermostats with each of them being installed as normal (spring towards the block).
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 #255290  by boriquatwin
 
UPDATE!
I've changed the thermostat with gasket and flushed out the cooling system. Replaced the Antifreeze with Prestone 50/50. Couldn't find Zerex G-05. I did have a problem with car over heating and antifreeze boiling and spitting out from the little hole in the coolant reservoir. I assumed there was air in the system and I was correct. With the engine off, opened up the valve bleed, connected a clear hose from the valve to an empty container. I then kept squeezing the upper radiator hose until i got a clear flow from the valve with no bubbles. This may have been a little unorthodox but it worked. I was squeezing and refilling for about 20 minutes. Now car keeps cooler than before, does not over heat and the fan doesn't turn on as much as it used to.. which to me is a good sign as it tells me engine isn't over heating. ALSO.... after flushing and changing the coolant, I noticed my transmission has been much smoother!! It does not have the kick from 2nd gear to 1st when stopping anymore!!! If anyone has this transmission issue and you haven't changed the coolant, give it a shot. I believe the coolant passes near the transmission cooling lines which bad coolant may cause the transmission fluid to over heat?? Please correct me if I'm wrong gentlemen.

Thanks to Cory's (Grayslater) instructions on how to change coolant in the Knowledge Base section. Sorry, don't remember the exact name of the post.
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 #255295  by Bill Putney
 
boriquatwin wrote:UPDATE!
I've changed the thermostat with gasket and flushed out the cooling system. Replaced the Antifreeze with Prestone 50/50...
'All Makes All Models', Gabe?
...Now car keeps cooler than before, does not over heat and the fan doesn't turn on as much as it used to.. which to me is a good sign as it tells me engine isn't over heating. ALSO.... after flushing and changing the coolant, I noticed my transmission has been much smoother!! It does not have the kick from 2nd gear to 1st when stopping anymore!!! If anyone has this transmission issue and you haven't changed the coolant, give it a shot. I believe the coolant passes near the transmission cooling lines which bad coolant may cause the transmission fluid to over heat??...
The transmission fluid flows thru a heat exchanger in the radiator, so, yes - overheated coolant would raise the temp. of the transmission fluid. There may be something to your theory on running hot causing the 'bump shift' (not sure that is the only possible/common cause) - we'll keep that in mind for future reference - I don't think that has been suggested before when people have posted about bump shift.
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 #255296  by boriquatwin
 
Yes all makes and all model coolant.

As far as the transmission bump, not 100% sure thats the solution for all cars but it was 120% my solution. I had the bump every single day for months. As soon as I pulled out with new coolant and thermostat, it ran as smooth as a baby's butt. Many car owners don't realize transmission fluid can over heat and cause problems so I think a coolant flush and change would be a start.