How to properly bleed air from cooling system?

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Complete car newbie in training, mind you!

I always thought the bleeder valve(like a brake bleeder) was for bleeding air exclusively(thats it, done), but lately I've heard on some vids(ericthecarguy) and read in the manual about that being the 'initial' bleed but not the final one for apps like my Honda. Other apps may be different.

Basically, what I gather is that the bleeder is to get the 're-fill' volume right. When the bleeder is cracked open/level ground on 're-fill' from a block/radiator drain for instance. Then, with the radiator cap twisted to the 'first' lock position(not completely locked) start the car with the heater lever on highest but no fan running. The whole 'wait for cooling fan to come on twice' bit, but to close the bleeder once air bubbles are done. Then, you cut the car off, remove the radiator cap/gently squeeze at the top radiator hose to encourage any other bubbles to come out and make sure the level is most of the way up the fill neck.

Do I have that about right? I've seen vids like ericthecarguy on YouTube bleed the system by allowing it to run for a while with those adapters that mount in place of the rad cap so that the coolant bubbles up into this funnel. Like this one:

http://www.amazon.com/Lisle-24610-Spill-...9604&sr=8-1

Demonstrated here:
 
Procedures can really vary by vehicle. Have you checked the factory service manual?
 
OMG, be careful.

You can destroy a good engine with a steam bubble or a hot spot caused by improper procedures.

The setup varies WILDLY by platform. You need vehicle-specific instructions.
 
I have never seen the bleed off valve. To my knowledge, my Astro does not have one. I follow the same procedure without the fancy funnel, I just leave the cap off the radiator. I put the temp control on hot, and put the fan on so I can tell when the coolent is through the heater core. When the engine is up to temp, I top off the radiator and the overflow tank. I usually check the level a few days later to make sure the level is still in spec. I have never had a problem. I had some work done at a shop years ago and drove away, around 20 miles later I had no heat. They did not get all the air out of the system. So I pulled the cap myself and let the air come out. I was not happy - paid for a complete repair and had to finish the job....
 
My truck has a coolant pipe with a hex plug on it that you open to bleed the air out when filling the system back up. Or atleast i'm assuming that's when you're supposed to open it.
 
Originally Posted By: ltslimjim
Complete car newbie in training, mind you!

I always thought the bleeder valve(like a brake bleeder) was for bleeding air exclusively(thats it, done), but lately I've heard on some vids(ericthecarguy) and read in the manual about that being the 'initial' bleed but not the final one for apps like my Honda.

Don't sweat this; it's not that difficult, or that complicated.

For your car, here's the refill procedure that works, every time, easily:
1) turn interior heater to FULL-HOT (which should have been done during the drain procedure)
2) close block and rad drains (you DID use the block drain?)
3) open bleeder valve on upper rad-hose stub
4) stick funnel in rad filler neck (the narrower the funnel and the slower the coolant-feed, the better)
5) add coolant until it dribbles from the bleeder valve
6) close bleeder valve
7) start engine
8) jiggle upper rad hose a bit in case there are a few bubbles in there
9) after a few seconds, rad level will drop a bit; add more coolant
10) after maybe a minute, put rad cap back on all the way; coolant may be rising by this point
11) make sure reservoir is filled an inch ABOVE the "max" line
12) allow engine to idle until rad fan comes on twice
13) allow to cool for several hours (overnight is best)
14) inspect reservoir level; it should be LOWER than it was before you started the engine
15) remove rad cap and make sure level is up to the very top, wetting the bottom of the rad cap

Note: In very cold weather, the rad fans may take ages to come on.

Air in your Honda's system is self-purging. All it takes is time.
 
x2. I do the same by filling it up, running it until the fans come on and check the level the next day.

I'll usually find the radiator low (as the system is full of coolant and all the air is up top) and i'll top it off and be done with it, checking it the following day to make sure it's absolutely PERFECT.
 
Wow, self-purging the air by moving all air to the radiator top over time?!
crazy2.gif
Another win for the Honda crowd!
banana2.gif
Haha!

thumbsup2.gif


Thanks guys, no worries. I just want to get the conventional Prestone Green all makes/models pre-diluted out of here. Replaced my radiator cap yesterday it was starting to deteriorate, though no idea how long the PO left this cap on. It seemed at least 5 years old or more. The bottom rung on the plunger was starting to fray/tear away.

Artem, Tegger...do either of you recommend HG Type-II or old school green for older Civics like mine? I looked at the new lineup of Beck/Arnley fluids, and the coolant specified was their green concentrate, not the 'Type-II' equivalent.
 
You could always look for one of these.

You can normally score them on Craigslist or Ebay for $50.00 or less, or you can get the off-shore made version for a reasonable price. While it may seem unnecessary, this is definitely the best way to fill a cooling system. As an added bonus, it'll tell you if you have any leaks in the system.
 
Originally Posted By: ltslimjim
Artem, Tegger...do either of you recommend HG Type-II or old school green for older Civics like mine? I looked at the new lineup of Beck/Arnley fluids, and the coolant specified was their green concentrate, not the 'Type-II' equivalent.

Personally, I do not recommend anything but genuine Honda coolant. Ever. I don't care how "good" anybody says aftermarket coolant is.
 
+1

The only fluid I'll put in my car that isn't made by Honda is oil, and I'm even thinking about moving to that now that I'm running 0w-20.
 
Okay, I'm not OCD about Honda only in other areas, but the cooling system reasoning makes sense; especially if I'm going be trying to avoid 2-EHA all together. I've got conventional green in there now. My concerns, though, is the amount of coolant needed to rinse out the old until I can get a proper 50/50 mix since they don't offer the Type-II HG in concentrate.

The Premium offering from B/A says it does not contain 2-EHA.

Quote:
Beck/Arnley Premium OE Antifreeze/Coolant is an Ethylene Glycol based Antifreeze/Coolant formulated for Asian automobile engine cooling systems that specify the use of “Green Concentrate” Antifreeze/Coolant.

Beck/Arnley Premium OE Antifreeze/Coolant utilizes Phosphated Organic Acid Technology also known as Hybrid Organic Acid Technology (HOAT) and contains no amines or borates and is free of silicates that may harm water pump seals and cause gel formation which may clog the radiator. MIX WITH EQUAL PARTS DISTILLED WATER.

Beck/Arnley Premium OE Antifreeze/Coolant provides superior corrosion and rust protection of water-cooled automobile engine cooling system components and meets ASTM D-3306.


FAQ link:

FAQ

No 2-EHA but this one sorta bothered me:

Quote:
• In actuality, all of our coolants can be combined with the only negative effect
being the reduction of the change interval to that of the concentrate (typically,
30K miles)


Sales pitch and not really recommended practice AFAIK.
 
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