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Old 10-12-2012, 06:45 AM
robertobaggio20 robertobaggio20 is offline
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Join Date: Oct 2009
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Originally Posted by Larrick View Post
Thanks for the information. It is 5:30 am. I can not sleep thinking about it! A few more question please.
Is there any reason that a cooling system will not be able to eliminate all the air?
If there is a head gasket problem, can air be being introduced into the system as it trying to be bled?
I researched a "ticking" sound coming from the top,front of the engine. Most popular explanation is a loose spark plug followed by lifter, loose belt, lose pulley and water pump going bad.
If it were the valves, common opinion (internet) says that it is not a problem and some suggest a 5W50 oil to cure the noise.
The spark plug is easy to check.
How much slack should be in the belt? Isn't there just one adjustment position?
I have always thought that the exhaust contained my vapor than I liked but it has been doing that for a long, long time.
It was cool and we had some rain and mist conditions yesterday but the BMW did it much more than my truck.
Wouldn't I need to loose considerable coolant to make the car overheat? Assuming I have the air out of the system.
Why can the engine run for more than an hour at idle (as I tried to bleed it) with the temp gauged pinned at the 1/2 mark but run a little hotter when on the road (and eventually overheat)?
I would think that the engine would cool better while while being driven gently. (more air flow and coolant flow) Is that situation an indicator of a bad water pump?
The pump can not keep up? Will a bad (weak) water pump make it harder to bleed the system also?
I will report back. Thanks again
Larrick sir,

These are good technical questions. However, I've decided to answer this later. I think you're overthinking this at this stage. However, I will say one thing. If your engine has had vapour out the tailpipe all the while, and was not losing coolant abnormally, then its probably fine and is not a symptom behind your current issue....that would be a safe assumption.

Now, back to your car. I'd like you to do the following. Firstly, bleed your radiator the way you should. Secondly, let the car idle for 30 minutes with the air conditioner switched off....monitor the temp gauge. Third, drive the car for 30 minutes and see if its ok.

Before all of this, check your fuse box and ensure that your auxiliary fan fuses are working perfectly.

Another thing....if you've been adding too much water to your radiator, please put some cheap off-the-shelf coolant in right away. Spend $5 or less. Maybe you could get that before you begin the bleeding process. Coolant holds higher temperatures better.

After that please report your results.

There is a good possibility that you may just have a buggy temp gauge. I had that a few days ago and luckily I remembered that I had a spare that I managed to dredge out. I swopped it in and it almost works perfectly (almost). You may be having the same problem. I don't trust your son's reports of the temp situation, I believe if you were there you would have a better global diagnostic sense of things. I recall that this is not the first time that you've worked on his car, so I believe you're the man when it comes to machines, so please get behind that wheel sir.
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