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Old 10-12-2012, 12:11 AM
robertobaggio20 robertobaggio20 is offline
Location: earth
Join Date: Oct 2009
Posts: 3,403
Mein Auto: car
You are not supposed to bleed anything under pressure. You've clearly misread something.

I once encountered a diagram of our radiator. The expansion tank connects to the radiator with a passage for water to flow back and forth between both depending on conditions. The bleed screw is located at the top of one of the main radiator passages.

Please follow my instructions to the letter. Do not improvise, at least for now.

1. Bleeding the radiator is a simple thing. If you're having trouble with it, or if you read instructions anywhere that make it sound complicated, you or they are doing it wrong. This is very important for you to internalise and use as a you need to unlearn alot of wrong stuff you've picked up over the years. Too many people over here seem to have problems with something that I find so simple. This is irritating because I initially tried just about all the unnecessary ideas I read about here (such as parking the car on an incline etc) to make sure my radiator was purged of bubbles, before realising after many months that it doesn't matter.

1. Remove the rad cap and bleed screw.
2. Fill up water/coolant in the expansion tank until water runs from the bleed screw. If bubbles run out, keep filling water until they stop.
3. Start the engine.
4. Activate max heat and max blower on your cabin heater, if it is working even partially. If it does not work at all, you can ignore this.
5. Wait till the engine reaches operating temperature. Do not rev the engine at this time, coolant will spill everywhere.
6. When it reaches operating temperature and you've got cabin heat (should take around 10 minutes or less), fill up more coolant into the expansion tank. Water will run out the bleed screw, along with any bubbles.
7.1 When bubbles stop running out and you've only got coolant, fix the bleed screw back....while the coolant is running out of the bleed screw. You will be able to do this somewhat by hand and then you can tighten it with a screwdriver etc. If you don't time this perfectly, don't worry. Air doesn't get sucked in, and even if it does its not much and won't matter to the engine.
7.2 This will not take longer than 5 minutes after your engine has reached operating temperature. If you need more time for this then 5 minutes.....come and rebleed the radiator 2 days later after driving. If, during rebleeding you notice alot of bubbles,...then rebleed 2 days later again after more driving. If you notice alot of bubbles still, you might have a problem with your engine. NOTE : if you notice a few bubbles each time you bleed, this is normal.
8. Fill up the expansion tank to the brim, then tighten down the rad cap on top of that. Some coolant may spill, its ok. Don't worry about compressing coolant etc. Never happened.
9. Coolant levels will adjust and come down during driving over the next 2 months. This is normal. Open your rad cap and top up with water at least once every 2 months. To make it easier to remember, just top up water once every month instead.
10. Get a new rad cap and a new bleed screw. Always better to be safe than sorry, and these things are under $15 for both together. Keep the old bleed screw as a spare.

If coolant levels drop so fast that you need to top up water once a week, you've got a problem somewhere. The pressure test with the radiator would be something you'll need to do to check it out. If that's ok, then you'll need to look for leaks and trace faults to the engine.

Its always a good idea to use cheap, brightly coloured, and strong smelling coolant that is sold at walmart. The OEM coolant is too expensive and too light will be hard to isolate leaks if they occur....and because it doesn't have a strong smell, if any coolant hose ruptures, you won't get a warning through a strong coolant smell invading the cabin. This happens far more quickly than a red line on your temp gauge, and so gives you more time to stop the engine and react to things.

For good measure, please check your auxiliary fan's fuses in the fuse box to make sure that your aux fan is working fine. It has a secondary cooling function along with the fan clutch. In fact, I've just removed the fan clutch from my car and am fully cooled by the aux fan and its coolant temperature sensor alone. The car drives better and there's alot more space in the engine bay to see stuff.

Last edited by robertobaggio20; 10-13-2012 at 07:08 PM.
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