LT4 - Should I flush and replace coolant?
Pro
Joined: Aug 2001
Posts: 571
Likes: 0
From: Redmond WA
Re: LT4 - Should I flush and replace coolant? (FoolCrzy)
In case you haven't read it somewhere before, draining the coolant is best acheived throught the knock sensors. The petcock barely drains anything, get under there and find the knock sensors which are located on either side of the oil pan. They're covered by a metal guard that is held on by two 10mm nuts on the oil pan rail, remove the guards and then pop off the electrical connectors. The sensors themselves come off with a big socket, I think it was either 21mm or 3/4, I don't remember exactly. Get them loose with the wrench then get the bucket underneath and finish with your hands, the coolant will gush out fast. Make sure the bleed screw and cap are opened. Don't try to get away with just one sensor, equal amounts came out of both sides on mine.
Good luck,
Sam
Good luck,
Sam
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
Re: LT4 - Should I flush and replace coolant? (LT4Sam)
Anybody try using compressed air? I was thinking that if you put compressed air thru the heads, it would push coolant out of the block without messing with knock sensors. I was thinking about connecting a low pressure air hose to the small return line clamped to the passanger's side radiator tank. This line goes to the back of the heads on the LT1/LT4 reverse flow system.
Will this work?
Will this work?
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Drifting
Joined: Mar 1999
Posts: 1,250
Likes: 1
From: Greensboro NC
Re: LT4 - Should I flush and replace coolant? (Mez)
Good way to blow up your heater core!!!
Best is to remove the knock sensors, but you can also back flush the engine by removing the thermostat housing and holding a garden hose in there and flush unitl clear water comes out of the other side....the refill with two gallons anti freze concentrate and top off with water....that'll give you 50/50 mix
Best is to remove the knock sensors, but you can also back flush the engine by removing the thermostat housing and holding a garden hose in there and flush unitl clear water comes out of the other side....the refill with two gallons anti freze concentrate and top off with water....that'll give you 50/50 mix
Anybody try using compressed air? I was thinking that if you put compressed air thru the heads, it would push coolant out of the block without messing with knock sensors. I was thinking about connecting a low pressure air hose to the small return line clamped to the passanger's side radiator tank. This line goes to the back of the heads on the LT1/LT4 reverse flow system.
Will this work?
Will this work?
Race Director
Joined: Oct 2000
Posts: 14,064
Likes: 1,166
From: N. Alabama
Re: LT4 - Should I flush and replace coolant? (Patrick96LT4)
If you over torque the sensors, you will destroy them. Follow directions. Replace hoses and pour distilled water/dex cool into radiator opening (hose off) with bleed screw open to allow air bubbles to escape. Raising front of car is also helpful to send bubbles to front. Not hard to do at all. Just requires a plan. Replace hoses, too. Be sure to put silicone inside mouth of each new hose. Do Not Overtighten new hoses, just snug. (I'll bet you knew all of this, anyway) :)
Pro
Joined: Jan 2003
Posts: 567
Likes: 0
From: Oswego Illinois
Re: LT4 - Should I flush and replace coolant? (vader86)
I read in corvette fever that when you flush your coolant with water should you do it while the engine is runing. I am in the process of installing a superram base manifold only not the whole gig :cry I just finished removing the thermostat housing and coolant is all in the inside should I worry about this when I remove the intake or will it be ok and not leak out?
