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Car overheating, need help with bleeding coolant system

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  #1  
Old 09-08-2009, 10:46 PM
upmysleeve's Avatar
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Default Car overheating, need help with bleeding coolant system

Ok, so I live in Miami, so I don't really need heat or a thermostat(I think). When a pipe on the heat exchange broke, my mechanic bypassed it. My car has always run with the temperature gauge in the middle, and gets hot if the car idles for too long.



Recently I had to replace the heater hose, and my mechanic let some guy finish the installation who didn't bleed out the system. I bled the system from the expansion tank myself with water.

Im wondering what the best method would be to bleed the system again, and replace the water with coolant, seeing as the heat exchange is already bypassed?

btw: how hard is it to remove the thermostat?
 
  #2  
Old 09-09-2009, 01:43 AM
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as far as bleeding the heater hoses, If the original style are still there, One of them will have a small hole in it about half an inch from the end. you pull it off where the hole will let the air and coolant out and fill the expantion tank. I had to unbolt the expantion tank to get it above the bleed hole.

For the thermostat. There are differing points of veiw on removing them, one being that coolant circulates to fast an never has enough time to take the heat out of the engine, another is that it will cavitate in certain places and cause hotspots(BAD). Taking it out requires alomst the same access as to do a timing belt change but they make 160 degree ones if that tickles your fancy.
 
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Old 09-09-2009, 02:26 AM
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flyboy... never seen u post on here yet.. clean ride.. whut front bumper u got? u got a lip on there too? anyways clean car mayne

but yea no thermostat = fail... u want/need one... especially in hot humid conditions
 
  #4  
Old 09-09-2009, 05:45 AM
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^^ agreed with the thermostat, if the engine never gets warmed up properly gas mileage will be going to crap because the fuel injectors are sending out more fuel to try to warm up the engine
 
  #5  
Old 09-09-2009, 11:06 AM
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The heater hosed is VERY snuggly bypassed with an L pipe. Do I still need to bleed it from there? I found it very hard to remove the hoses from that pipe manually.
 
  #6  
Old 09-09-2009, 11:22 AM
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Coolant does not really cool..Its main jobs are too keep the water from freezing and provided corrosion protection. A slight side effect of glycol is it raises the boiling point of water to help prevent steam pockets which WILL cause the car to overheat. However, this function is mostly taken care of by the pressure cap (high pressure water boils later). The thermostat insures proper running temp and faster warmups too that temp.

So, while you really do not need coolant, you do need to add corrosion protection and have a thermostat.
 
  #7  
Old 09-09-2009, 11:45 AM
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I just bled the heater hose. There had to have bee air pockets in the system because a lot of coolant came out. I unsecured the expansion tank and held it high while filling it with water. Now if I want to replace the water with coolant, do I need to repeat everything all over again or can I bleed from only the expansion tank? I went through a few bottles of coolant before I realized what the problem was, and I don't want to waste any more money.
 
  #8  
Old 09-10-2009, 10:31 PM
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The easiest way I have done it is fill up your car with the coolant because if you use just water parts rust. Im pretty sure audis waterpump is aluminum and maybe the thermostat? the coolant has some lubricants in it which really helps all the parts. Once you have filled the car let it run for like 10 minutes with the cap off and it will naturally work out all the air bubbles. You may have to do this more then once. And yes you need a thermostat stupid not to replace it your just asking for problems if your t-stat is bad then your waterpump is probably on its way as well
 
  #9  
Old 09-10-2009, 10:33 PM
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drink some beer and forget about your problems
 
  #10  
Old 09-10-2009, 10:48 PM
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this is how i do it And listen it works you fill it up with coolent to the line leave the cap off than tip the car over on the side with a jack and it will burb out
 
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