coolant levels after flush ??
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I've done this on my boat engine's coolant system with great sucess and would love to use this on our LT1 engines -- but wonder how with all the 'ports' high on the engine.
So, to what do you 'connect' the shop-vac, to allow evacuation of all the lower sections of the block?
So, to what do you 'connect' the shop-vac, to allow evacuation of all the lower sections of the block?
With the engine warmed and the thermostat open, the blown air will force ALL the coolant out of the system.
Hold the hose in place until nothing but air comes out.
Last edited by onedef92; Feb 18, 2009 at 11:42 AM.
Drifting
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From: 1994 LT1 Coupe 6-speed with FX3 & 2000 LS1 Vert 6-Speed with F45 Hunterdon County, NJ
Place a large pan under the radiator petcock, open the petcock valve, remove the radiator cap, then put the Shop Vac hose over the radiator opening.
With the engine warmed and the thermostat open, the blown air will force ALL the coolant out of the system.
Hold the hose in place until nothing but air comes out.
With the engine warmed and the thermostat open, the blown air will force ALL the coolant out of the system.
Hold the hose in place until nothing but air comes out.
My experience is thermostats are slow to open and close pretty quickly after the heat source is removed (e.g. engine or stove when testing) -- so this would have to be done after engine is fully up to temp and very quickly thereafter, TRUE?
Have you ever 'measured' the amount of coolant you were able to 'blow' out of your LT1 engine (or put back in) and did it very closely match its capacity (18 qts +/-)?
Drifting
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From: Charlotte NC
Place a large pan under the radiator petcock, open the petcock valve, remove the radiator cap, then put the Shop Vac hose over the radiator opening.
With the engine warmed and the thermostat open, the blown air will force ALL the coolant out of the system.
Hold the hose in place until nothing but air comes out.
With the engine warmed and the thermostat open, the blown air will force ALL the coolant out of the system.
Hold the hose in place until nothing but air comes out.
I'm guessing by radiator opening we are talking about the surge tank.
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Presume you've done this on your 1992 Vette (per profile). By 'radiator' do you mean the 'surge tank' (black tank by windshield)?
My experience is thermostats are slow to open and close pretty quickly after the heat source is removed (e.g. engine or stove when testing) -- so this would have to be done after engine is fully up to temp and very quickly thereafter, TRUE?
Have you ever 'measured' the amount of coolant you were able to 'blow' out of your LT1 engine (or put back in) and did it very closely match its capacity (18 qts +/-)?
My experience is thermostats are slow to open and close pretty quickly after the heat source is removed (e.g. engine or stove when testing) -- so this would have to be done after engine is fully up to temp and very quickly thereafter, TRUE?
Have you ever 'measured' the amount of coolant you were able to 'blow' out of your LT1 engine (or put back in) and did it very closely match its capacity (18 qts +/-)?
Correct again. The radiator surge tank near the windshield. Be sure and keep your TB bleed valves CLOSED during the procedure. You won't open them until you refill the coolant system, per standard procedure.
I didn't measure the coolant that was blown out, but I can tell you no coolant at all came out of the knock sensors after I removed them to test my theory. My method definitely saves time from having to remove the knock sensors.
Last edited by onedef92; Feb 20, 2009 at 10:15 AM.
Drifting
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From: 1994 LT1 Coupe 6-speed with FX3 & 2000 LS1 Vert 6-Speed with F45 Hunterdon County, NJ
... will do it next doing coolant on our LT1 and LS1 (figure if it works for one... ).
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Correct. Your engine should be warm, NOT HOT (for safety purposes) with the radiator fully opened at operating temps. Perform the procedure as soon as you know the 'stat is open.
Correct again. The radiator surge tank near the windshield. Be sure and keep your TB bleed valves CLOSED during the procedure. You won't open them until you refill the coolant system, per standard procedure.
I didn't measure the coolant that was blown out, but I can tell you no coolant at all came out of the knock sensors after I removed them to test my theory. My method definitely saves time from having to remove the knock sensors.
Correct again. The radiator surge tank near the windshield. Be sure and keep your TB bleed valves CLOSED during the procedure. You won't open them until you refill the coolant system, per standard procedure.
I didn't measure the coolant that was blown out, but I can tell you no coolant at all came out of the knock sensors after I removed them to test my theory. My method definitely saves time from having to remove the knock sensors.
Can you flush all the coolant out via the throttle body coolant hoses or the heater hoses? I figured I could pop those off, and run water in there. But then again, I dont' know where they drain to.
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L98's don't have a surge tank by the windshield. I think your method would work better with the thermostat removed. Don't have to worry if it is open or closed.
Can you flush all the coolant out via the throttle body coolant hoses or the heater hoses? I figured I could pop those off, and run water in there. But then again, I dont' know where they drain to.
Can you flush all the coolant out via the throttle body coolant hoses or the heater hoses? I figured I could pop those off, and run water in there. But then again, I dont' know where they drain to.
However, when I squeezed the TB hoses and coolant after the system was empty, nothing came out. So I assume the system was completely evacuated by this time.
Or, if any amounts remained, they were negligible.
And I agree. Removing the thermostat is a good idea. That way, you don't have to worry about the system being opened or closed.
Last edited by onedef92; Mar 16, 2009 at 03:05 PM.
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I've never removed the TB hoses during this procedure, so I don't know.
However, when I squeezed the TB hoses and coolant after the system was empty, nothing came out. So I assume the system was completely evacuated by this time.
Or, if any amounts remained, they were negligible.
And I agree. Removing the thermostat is a good idea. That way, you don't have to worry about the system being opened or closed.
However, when I squeezed the TB hoses and coolant after the system was empty, nothing came out. So I assume the system was completely evacuated by this time.
Or, if any amounts remained, they were negligible.
And I agree. Removing the thermostat is a good idea. That way, you don't have to worry about the system being opened or closed.
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Anyways if so, then I'd just remove the thermostat and have the car cold.
So, take thermostat out and bolt back the housing.
Open petcock and drain radiator.
Put blower in radiator cap opening and turn it on to blow?
Where exactly is the air blowing in the radiator to push all the coolant out of the system? I'm wondering if this is something that is best used via the surge tank instead of the radiator. As I don't see how it would work through the radiator.
I can see it working through the surge tank as I believe that is the highest point in the coolant system. So by blowing air in there, with gravity, it would force the coolant out. But I don't have a surge tank. I guess I could try it via the heater hoses and the throttle body hoses to see what that does.
Does anyone have a photo diagram of the cooling system for the L98 engine and LT1 engine? That would give us a better idea of where the coolant flows.
