coolant system bleeding air

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muleys86

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Hey all, Ive got a 99 Monte Carlo Z34 with the 3.8 v6. 210xxx miles, still runs decent. The 3.8 engines have a coolant elbow issue being plastic and have been replaced with aluminum ones along with a new rad. The problem I'm having is burping the air from the system. The thermostat housing has the bleeder screw in it. Ive done everything I know to fix this and no luck. I know to top off the coolant level then bring to operating temp, loosen the bleeder screw, and repeat. 4 or 5 times hasn't done it, so is there a step I'm not doing?
Temp sender has been r&r temp gauge is reading only 140 degrees. Heat works, low coolant light stays on. Any help is greatly appreciated. Anybody have or used the spillproof funnels from Lisle Tools? That looks like a good idea.
Thoughts? thanks again Muley
 

1987 GMC Jimmy

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Just did this a few weeks ago as it got cooler here. I don't have any kind of bleeder screw in mine, though. I didn't see you mention turning it to max heat and turning the blower on. The heater core is the high point of the cooling system so that's probably where the air is hanging out. You might could even park it on an incline with the front being higher than the rear. Add this to what you've been doing, and it should work fine. I didn't use a spill proof funnel. I just used a fat, run of the mill funnel that I have and stuck it in the radiator fill.
 

towman

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jack the front of the car as high as you can get it, tha will help burp out the air
 

74 Shortbed

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Drill a .050 hole in the t-stat and you'll bleed the air as you fill the system, don't know why they don't come with a bleed hole to begin with..
 

muleys86

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Thanks guys for your info. Ive done everything suggested, more and no success. A guy at napa told me to fill with coolant, warm engine then bleed, let cool and that this could take 5/6 or more times. All day!? I'm gonna keep at it, wish me luck. Thanks again, Muley
 

ScottyB

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Just had a similar issue with an 02 Buick LeSabre. All traditional attempts at bleeding were unsuccessful. A buddy of mine who is a retired mechanic. He told me to top off the coolant and overflow (to proper level) and then drive the piss out of it. Take it out for a 15-20 minute drive, preferably with hills involved. Let it cool down and DO NOT CHECK ANYTHING. Don't even tempt yourself by opening the hood. Then take it out again and drive it hard again for 15-20 minutes. Check it after it has cooled down and it should be burped. Top off your fluids and you should be good to go. YMMV
 

muleys86

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Thanks ScottyB, Ill try that. I'm at the point Ill try anything. Got some cold weather and light snow in the forecast, nothing severe I hope. Got my Scottsdale going so Ive been driving that. Again thanks. Muley
 

bucket

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I've never had any trouble with those systems. Fill while the bleeder is open, close the bleeder when fluid starts coming out. Then finish filling. Start the car and open the bleeder until a steady stream of fluid comes out, close bleeder. Fill up the bottle and go for a drive. Let the car cool and top it off. Done.

The low coolant sensor in the radiator is known to fail, especially after the coolant has been drained and refilled. If you have heat, the engine runs at the proper temps, all is probably well. Just a defective low coolant sensor.
 

Honky Kong jr

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I know its old but i use a vacuum bleeder. Hooks to comprezsed air and creates a vacuum in the coolant system to the point of collapseing the hoses flat then open a valve and it draws coolant into the system which is in a vacuum state. Vw and Audis are horrible for being air bound.
 

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