One last throttle body bypass thread!
Thread Starter
Instructor
Joined: Jan 2007
Posts: 112
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From: Belleville Wisconsin
One last throttle body bypass thread!
Ok, Ok. I know bypassing the good ole' throttle body with a couple clamps and a piece of pipe is mainly for looks, and if any HP gain is there it's not felt SOTPs. I know this from the 4,000,000 previous threads on this subject. But I think I'm going to do this anyway just for fun on my 1992. My question is: once I remove the first and/or second hoses from the TB, can I expect to get a "green" bath? Is there that much coolant sitting in these hoses up by the TB? Do I really need to drain the radiator down a bit to avoid turning into the Incredible Hulk(and even worse.....dosing the Opti!!!!). If so, then this almost sounds to me like more work then it's worth. I suppose I need to "burp" the cooling system too, huh? Those who have done this on an early LT1 please chime in if'n you will. Also, is there a quick and easy way to "burp" the cooling system. Never really had to do this before.
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clamp the hoses. Don't expect zero coolant leaks 
Thread Starter
Instructor
Joined: Jan 2007
Posts: 112
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From: Belleville Wisconsin
[QUOTE=PLRX;1570724347]clamp the hoses. Don't expect zero coolant leaks [/QUOTE
Are you saying to clamp the hoses BEFORE I remove them from the TB? I know I have to clamp the two hoses and the brass fitting that goes between them after I have them removed. But you are saying to clamp the hoses a few inches up on each BEFORE I remove them from the TB, right??? Also, I guess I'll still have a little coolant from the ends of the hoses and TB anyway. I better put a plastic sheet and some rags under the TB and over the Opti area regardless, huh? If the clamping will stem most of the coolant flow, then this may not be too big of a deal. One million thanks. Anyone else have an opinion?
[/QUOTEAre you saying to clamp the hoses BEFORE I remove them from the TB? I know I have to clamp the two hoses and the brass fitting that goes between them after I have them removed. But you are saying to clamp the hoses a few inches up on each BEFORE I remove them from the TB, right??? Also, I guess I'll still have a little coolant from the ends of the hoses and TB anyway. I better put a plastic sheet and some rags under the TB and over the Opti area regardless, huh? If the clamping will stem most of the coolant flow, then this may not be too big of a deal. One million thanks. Anyone else have an opinion?
Burning Brakes
Joined: May 2009
Posts: 787
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From: Hialeah Florida
I put the bypass kit about 2 weeks ago. When I took off the hoses a good amount of water came out of the TB not much from the hoses. Make sure to stuff some rags underneath to absorb it after you take off each hose. And plug the TB holes for that professional look. I didnt burp the system either and everything has been a-ok. 
Le Mans Master
Joined: Feb 2000
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From: Kempner Texas
I did my son's 96 LT1 yesterday and didn't have hardly any coolant flow out. Of course, his engine had just been re-installed and the coolant tank (the one with the radiator cap on it) was empty.
I placed a thick towel on top of the OPTI when filling and bleeding air from the system with the bleed screw open.
Before re-routing his I didn't do any research on it, I just went by what looked logical to me. Just as a check on myself, how do you plan to by-pass yours?
Jake
West Point ROCKS!
I placed a thick towel on top of the OPTI when filling and bleeding air from the system with the bleed screw open.
Before re-routing his I didn't do any research on it, I just went by what looked logical to me. Just as a check on myself, how do you plan to by-pass yours?
Jake
West Point ROCKS!
Safety Car
Joined: Jan 2008
Posts: 3,939
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From: Vero Beach Florida
There should be a little drainage but if you are doing this over a 92 with an Opti I would be careful, make sure car is cold and open the radiator holding tank cap to relieve any pressure. To finnish the job go get some rubber caps that you can install over the old pipe fittings on the TB.
Thread Starter
Instructor
Joined: Jan 2007
Posts: 112
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From: Belleville Wisconsin
There should be a little drainage but if you are doing this over a 92 with an Opti I would be careful, make sure car is cold and open the radiator holding tank cap to relieve any pressure. To finnish the job go get some rubber caps that you can install over the old pipe fittings on the TB.
Thread Starter
Instructor
Joined: Jan 2007
Posts: 112
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From: Belleville Wisconsin
There should be a little drainage but if you are doing this over a 92 with an Opti I would be careful, make sure car is cold and open the radiator holding tank cap to relieve any pressure. To finnish the job go get some rubber caps that you can install over the old pipe fittings on the TB.
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Safety Car
Joined: Jan 2008
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From: Vero Beach Florida
How much time are you going to be driving your Vett when its below zero out. If you are only starting it I would not think it would be a problem
Last edited by floridamale; Jul 10, 2009 at 03:57 PM.
Le Mans Master
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From: Kempner Texas
If you want to minimize the amount of coolant flowing onto the Opti, you can prepare and have at the ready a few hoses draped to the outside of the car to act as drain hoses.
Then when you remove a hose quickly slide on the drain hoses. Any coolant will flow onto the ground/floor and not into the engine compartment. No need to clamp them; just sliding them on should be enough. Thick towels on top of the Opti is a good idea too.
Let's see; you'll need one, maybe 2' long for the steam pipe which is on the passenger side of the intake, one for each side of the TB hose bibs and, finally, the long one that 'T's into the radiator can just be directed away.
I don't expect you'll lose more than a quart if the radiator cap is loosened to relieve any pressure. There's not much in the TB itself; most of it will come from the hoses and steam pipe.
This is how I'd do it.
Jake
West Point ROCKS!
Then when you remove a hose quickly slide on the drain hoses. Any coolant will flow onto the ground/floor and not into the engine compartment. No need to clamp them; just sliding them on should be enough. Thick towels on top of the Opti is a good idea too.
Let's see; you'll need one, maybe 2' long for the steam pipe which is on the passenger side of the intake, one for each side of the TB hose bibs and, finally, the long one that 'T's into the radiator can just be directed away.
I don't expect you'll lose more than a quart if the radiator cap is loosened to relieve any pressure. There's not much in the TB itself; most of it will come from the hoses and steam pipe.
This is how I'd do it.
Jake
West Point ROCKS!
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From: O'Fallon Missouri
Le Mans Master
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From: Kempner Texas
As far as burping, all I did was what's listed in the Owner's Manual. I loosened the bleed screw on top of the thermostat housing (after placing a heavy towel on top of the Opti). I then began filling the cooling system while watching for coolant flow from the open bleed screw.
I added a quart of coolant then a quart of water, etc. for mixing purposes.
When flow came out of the open screw in a steady stream I tightened the bleed screw and continued filling until coolant was about 1/2" below the top of the fill tank. I then filled the over-flow tank to a little above the COLD level.
Since the engine was completely empty after the heads and cam installation, I needed a over two gallons of Prestone anti-freeze and a similar amount of distilled water.
I then fired the engine at let it fully warm up at idle, 200F. Then shut it down and let the engine cool to ambient temp, 102F in Texas. The cooling system automatically adds or expels coolant as needed. The new valve springs needed this warm-up/cool-down procedure too.
Just how I did it last week.
Jake
West Point ROCKS!
I added a quart of coolant then a quart of water, etc. for mixing purposes.
When flow came out of the open screw in a steady stream I tightened the bleed screw and continued filling until coolant was about 1/2" below the top of the fill tank. I then filled the over-flow tank to a little above the COLD level.
Since the engine was completely empty after the heads and cam installation, I needed a over two gallons of Prestone anti-freeze and a similar amount of distilled water.
I then fired the engine at let it fully warm up at idle, 200F. Then shut it down and let the engine cool to ambient temp, 102F in Texas. The cooling system automatically adds or expels coolant as needed. The new valve springs needed this warm-up/cool-down procedure too.
Just how I did it last week.
Jake
West Point ROCKS!
Le Mans Master
Joined: Feb 2000
Posts: 9,715
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From: Kempner Texas
I guess the principles that same, though - right? Drain it outside the engine bay.
Thanks for that heads-up.
Jake
West Point ROCKS!
