Yes @George_San_Jose1 I’ve been using this for over a year: https://www.ecstuning.com/b-schwaben-parts/schwaben-coolant-vacuum-fill-tool/024948sch01a/
You don’t seem to understand what the bleed screw is for if you are operating it after the engine and coolant has cooled down.
You should fill the system with the bleed screw unscrewed and venting…fill the system as far as you can till it flows out of the bleed screw… Tighten and then run the engine to heat up the coolant. Then allow the engine to completely cool down…cold, yes, possibly overnight…and then start up and run the engine till hot. Let it completely cool down again…till cold. This will force the coolant to expand and contract and burp itself. It will burp up the air and drink in solid coolant as it is supposed to do.
You can even crack the bleeder when it is heating up to operating temp…be careful here…there are pressures involved obviously. You want to burp air out while the coolant is expanding…not contracting or after it has contracted when cold. Opening the bleeder when cold will introduce air into your closed system… it should only be used when filling it up cold and also to help burp when it is heating up and coolant is expanding. Also helps to do this stuff with the nose of the vehicle elevated like on a steep gradient…not mandatory but it helps.
i got an 06 equinox w/3.4 and bad headgaskets last yr. still driving it. picked up an 05 yesterday with same issue. new radiator, new WP. new starter. new alternator. figured i cant lose much other than time. there is a tee hose setup under the brake booster area but i really think that is not the issue.
@Honda_Blackbird I’m familiar with how to use the bleeder screw. Yes, when filling the system from empty I leave the screw off so that air can fully purge from the system (if I’m not suing my vacuum bleeder). However the bleeder screw is at the highest point of the engine, so if any air gets trapped, that’s the only way to “burp” it.
When I say I open the bleed screw after it has “cooled down”, I mean after it has gone below boiling temp. If I were to open it while the engine was over 212F, the loss of pressure in the system could cause the coolant to boil, creating more air. If I open it at ~180F, I avoid boiling but ensure there is still some pressure in the system to drive the air out.
Still, my issue remains. I can completely “burp” the system of all trapped air (either traditional burping or via vacuum), drive the vehicle, and air will have been reintroduced somehow.
Are you including your heater core in the equation? Just be sure your cabin temp is on the Hot setting to include the core in the festivities it is part of the system, so…
OP, have you tried driving the front end of the car up on ramps (or jacking the front end and on jack-stands) when bleeding the air out of the cooling system? Sometimes the incline will make it easier. You could try tilting other directions too, tilt to the right, tilt to the left, hiking the rear end instead of the front, try them all.
If all that doesn’t help and you are using the vacuum gadget, either you have an undiagnosed head gasket leak or cooling system leak. It’s possible to have either of those that only occurs when the engine is in a certain condition or mode, hot for example. In other words it won’t show up when testing a cold engine. I had a leak on my Corolla where the inlet hose connected to the water pump that only leaked when hot and the coolant was right at the totally full level and the nose of the car was tilted down. If the coolant was slightly low, or the nose of the car tilted up, it wouldn’t leak, even if hot.
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Same issue here on 06 Equinox. Everything pointed at blown head gasket.
I replaced head gaskets, intake gaskets, and all related seals and gaskets from the block upward.
Old head gaskets looked good with no evidence of a leak, but replaced anyway, of course.
New overflow tank w/ new cap.
New thermostat.
New bleeder valve.
All hoses and couplings are bone dry.
Cooling fans work.
Floorboard below heater core is dry.
No longer overheating, but heater blows only lukewarm air at hottest setting.
Must still have air in system… correct?
Raised front end as high as safely possible on jackstands.
Bled air dozens of times following procedures outlined in many places online.
Still no heat in cabin.
Must be taking in air from somewhere?
The only thing left is the water pump???
Can the WP somehow be pulling in air as fast as I can bleed it out?
One thing is certain, this ridiculous cooling system somehow made it all the way into production on several GM models. If this is the best they can engineer, I’ll find another brand.
If anyone ever has major problems bleeding a particular system careful attention needs to be given to the rad cap and overflow etc.
Also …and very often overlooked is the heater core…it needs to be in the equation so it also purges its air out. Many times these new electronic heater controls dont do what you think they do…and sometimes can keep the core shut out of the festivities…
Just food for thought. I never met a system I couldn’t fully purge of air once all else was checked and verified.
Steely ted: you have air in system now but started with overheating issue?
Seller said equinox I got last yr was overheating. Head gaskets confirmed issue. i never drove it prior to purchase. Runs fine now. Good heat.
Got another nox this weekend. Pulled intake. Oil is milky. So, I assume it is head gasket.
Long, long ago when it became necessary to bleed air from cooling systems I found that drilling a 1/16" hole in the base of thermostats (those that mount above the cylinder head(s), and using 2psi +/- regulated air pressure connected to the cooling system overflow line made it possible to methodically loosen and burp air from all the hose connections and the bleeder screw without fail. I certainly suggest that anyone having a problem try that method.
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Yes I always do this with the key in the ON position and heat set to full hot and HVAC fan on.
Cavell,
Yes, started with overheat at idle issue.
Simplest things first, I replaced thermostat.
Still overheating, I assumed I still had air in system from thermostat change.
Couldn’t seem to get air out.
Started looking for source of air coming in and found crack in nipple on btm of overflow tank.
Replaced tank and still had overheating.
Checked cooling fans, AC fan working as it should, the other fan spinning weakly/slowly.
Bad bearing in fan.
Replaced fan.
New fan runs well, no more overheating at idle.
Still no heat in cabin, must still have air in system??
Bled air a dozen times. Cannot get any heat in cabin above lukewarm.
Still taking in air somehow?
The only way of overcoming system pressure to pull in more air?
Head gasket?
These engines well known for blown head gaskets.
Oil was not milky, looked fine, but only had a few miles on fresh oil change.
150k miles.
Overheat history.
Blown head gasket. Damn!
Changed both head gaskets and all seals and gaskets up from there.
Old head gaskets looked good, no evidence of leak.
Still no cabin heat.
Still taking on air somehow?
No evidence of heater core leak.
I can hear the hot/cold blend door operating as it should.
Very slight mist of coolant on my hand as I’m standing there looking at engine?
Hand was positioned near water pump.
I could see a tiny amount of coolant being slung from pump pulley.
Probably just from bleeder port right above pump dripped down onto pulley?
Could WP be creating a sort of venturi effect pulling in air?
Anyone have any advice on how to proceed from here?
Rod Knox, Ha! great name! I’ve heard of folks doing that little trick before. Sadly, this 3.4l’s thermo lives too low in system for that to work here. Thanks for your input tho. Any other thoughts?
Blackbird, can you advise me how to make sure there is no air in heater core?
side note. did you break any exhaust flange bolts/nuts when you removed the crossover? i only broke 1 bolt on the rear facing flange under the firewall. since head is off i could drill out the old bolt without too much grief.
i was somewhat surprised to see the crossover is not hard to remove.
my kid always wanted to put headers on his 3800 grand prix. never made that dumb mistake
I never removed the crossover. I removed the fwd exh manifold from head and from crossover. That gave me plenty of room to just push the rear manifold back once I removed the bolts. Getting to the plug wires was a bit of a pain though, both taking them off and putting them back on.
I found a screwed up valve cover bolt hole though, bolt just pulled right out. I had to install a helicoil in that spot. Luckily I had the right size in my box.
I found the water pump was definitely leaking. Just finished replacing it. Easy swap. Still no love though. Still not getting heat in the cabin after bleeding and bleeding.
I’m now thinking the blend door is not working. I can hear the little servo motor operate when I switch back and forth from hot to cold. Maybe linkage from motor to door is broken? I can feel plenty of heat in that area when I snake my hand up in there. If that’s not it, I’m out of ideas.
Turns out the blend door is broken. Lot of time wasted trying to bleed air from system because I couldn’t get heat to the cabin. One of the first things I checked was the blend door, but I didn’t crawl in there and get a visual, I just listened closely and could hear the motor operating. Lesson learned. If someone else is reading this in the future, verify door is actually moving when you’re checking for heat in cabin while bleeding air from cooling system.
I am having the exact symptoms as you. I have an e39 528. What i have done is drilled a hole through on the inside of the expansion tank. Now I get about 20 drives out of the car as opposed to 20 mins.