LT4 Coolant Bleeder Screws
Thread Starter
Instructor
Joined: May 2002
Posts: 187
Likes: 0
From: Cumming Georgia
LT4 Coolant Bleeder Screws
In order to properly refill the LT4 coolant system, the manual notes a requirement to open "both bleeder screws". While I have found one bleeder located on the body of the Thermostat housing, I have been unable to locate a second bleeder. Does anyone know where the second one is?
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
Re: LT4 Coolant Bleeder Screws (Eric 96)
I believe the shop manual is incorrect. I could only find the one on the thermostat neck and was not able to fill the system with just that screw open.
To bleed air out of the system after flushing, with the engine not running, I pulled the upper radiator hose off the radiator on the drivers side, poured a 50/50 mix of Dexcool and distilled water into the tank by the windshield until coolant started coming out of the disconnected hose. I reinstalled and tightened the hose clamp. I started the engine, poured in more coolant until it squirted coolant out the thermostat housing bleed screw.
The radiator drain in on the bottom passanger side. Its plastic, so be careful not to over tighten when you re-install. A side note, I did not use the "pills" and have experienced no problems. Should I add the pills??
To bleed air out of the system after flushing, with the engine not running, I pulled the upper radiator hose off the radiator on the drivers side, poured a 50/50 mix of Dexcool and distilled water into the tank by the windshield until coolant started coming out of the disconnected hose. I reinstalled and tightened the hose clamp. I started the engine, poured in more coolant until it squirted coolant out the thermostat housing bleed screw.
The radiator drain in on the bottom passanger side. Its plastic, so be careful not to over tighten when you re-install. A side note, I did not use the "pills" and have experienced no problems. Should I add the pills??
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Melting Slicks
Joined: Jan 2000
Posts: 3,418
Likes: 1
From: NW Chicago Suburbs
Re: LT4 Coolant Bleeder Screws
IMHO, the pills suck, they clog the heater core in Impalas, then you got no heat. They are there supposely to fix leaks. Just how the he11 can my system have leaks? I installed a new radiator, hoses and clamps, all GM OEM stuff. There better not be a freaking leak :mad
Eric
Eric
Melting Slicks
Joined: Apr 2000
Posts: 3,198
Likes: 2
From: Northern CA
Re: LT4 Coolant Bleeder Screws (silver & red CE)
The GM pills aren't for leaks, they are for keeping the pH balance of the long-life orange coolant. That's what I remember from the service manual.
You'll find opinions either way but I haven't experienced problems with the pills myself. Been almost 2 years now...
You'll find opinions either way but I haven't experienced problems with the pills myself. Been almost 2 years now...
Melting Slicks
Joined: Jan 2000
Posts: 3,418
Likes: 1
From: NW Chicago Suburbs
Re: LT4 Coolant Bleeder Screws (JasonL)
The GM pills aren't for leaks, they are for keeping the pH balance of the long-life orange coolant.
"Add six cooling system SEALER PELLETS, GM P/N 3634621..."
Adding six goo ***** to seal a non leaking system makes little sense to me.
Eric
