LT1 reverse cooling system not working
Wow... over complicating the **** out of bleeding coolant system going on up in here...
IMO one of the biggest mistakes people make when filling the engine/radiator with coolant is keeping the bleeder screws closed.
IMO one of the biggest mistakes people make when filling the engine/radiator with coolant is keeping the bleeder screws closed.
Haha, This is true. I gave my opinion.. Jack up the frontend and it usually bleeds right out with the bleeders in no time. Only thing I had good luck with in my 95.
Surefire way to have coolant system completely bled w/out having to jack a car up:
Open both bleeder screws
Pour coolant/water into radiator. A hiss will be heard from the bleeder from TB housing
When it starts to dribble coolant, close it.
Pour until radiator is full.
Close both screws
start engine or electric w/p if equipped
keep radiator open and watch coolant return line opening
you will start seeing coolant spit out here and there
keep eye on temp gauge if engine is running
pour coolant/water into radiator keeping it about half full (this way radiator will not overflow when engine starts getting warm)
once you see steady stream out of return line, fill radiator all the way up
close radiator
let system pressurize while still keeping eye on temp gauge (or start engine if all steps were done w/ electric pump)
once system is pressurized, open t-stat bleeder screw until a steady stream of coolant runs out. shut and let system pressurize again if needed
open top bleeder screw screw until steady stream flows
Close screw and drive
keep a container of water/coolant with you because coolant may still have minor air pockets for a few start cycles.
Whatever you do, do not open the top bleeder with the radiator open. That is the highest part of the cooling system. You open that air will get into cooling system and it will overflow the radiator.
easy peasy lemon squeezy
Open both bleeder screws
Pour coolant/water into radiator. A hiss will be heard from the bleeder from TB housing
When it starts to dribble coolant, close it.
Pour until radiator is full.
Close both screws
start engine or electric w/p if equipped
keep radiator open and watch coolant return line opening
you will start seeing coolant spit out here and there
keep eye on temp gauge if engine is running
pour coolant/water into radiator keeping it about half full (this way radiator will not overflow when engine starts getting warm)
once you see steady stream out of return line, fill radiator all the way up
close radiator
let system pressurize while still keeping eye on temp gauge (or start engine if all steps were done w/ electric pump)
once system is pressurized, open t-stat bleeder screw until a steady stream of coolant runs out. shut and let system pressurize again if needed
open top bleeder screw screw until steady stream flows
Close screw and drive
keep a container of water/coolant with you because coolant may still have minor air pockets for a few start cycles.
Whatever you do, do not open the top bleeder with the radiator open. That is the highest part of the cooling system. You open that air will get into cooling system and it will overflow the radiator.
easy peasy lemon squeezy
TECH Apprentice
iTrader: (2)
Joined: Jul 2010
Posts: 394
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From: Oklahoma City, OK/North Long Beach/Paramount, CA
nice to see u got a thread started im sure someone here will help you get it up and running or just take it to the closes shop and have them check it out for you but only if its free cuz i do that sometime when i cant find the problem or better yet check your regional forums and find someone who is close to you that is willing to check it out for you i did that before it wont hurt to ask. gl
i was driving up north to visit my buddy (150 mile drive or so) and a little over half way there i watched my water temp just immediately shoot to the red. pulled over and let it sit. end up the thermostat just magically failed me halfway through my journey in the middle of no where. after i got home i put in in boiling water (180 degree thermostat). wouldn't even budge. went and got a 160 thermostat, problem solved.
thermostat is easy to at least just check, take the elbow off, two bolts, bam. might as well just test it, you'll either find the problem or rule one thing out.
thermostat is easy to at least just check, take the elbow off, two bolts, bam. might as well just test it, you'll either find the problem or rule one thing out.
dude if you were just driving along and the temp shot up like that the water pump probably stopped circulating water......upon that happening it will get really hot really fast usually in under 30 seconds.......pull the radiator cap off and start the car up if there is water squirting out of the little hose that connects right at the top of the radiator (under the cap) then the pump is workign......if not you are not circulating water.......this should be circulating even with the thermostat closed and the engine cold and running............I'm saying its the water pump that took a dump on you....
Mechanical waterpumps just don't up and give out w/out making a retched noise or some sort of tell tale sign. Because of its physical connection to the engine it virtually impossible for the pump to give out unless something snaps. What it reads like is the he reconnected the hose and there was not enough coolant to keep the pump primed.
......if there is any air in the system it gets forced up to the highest point which is at the top of the upper hose and near the thermostat.....hence the bleeder on the top of the water neck i was driving up north to visit my buddy (150 mile drive or so) and a little over half way there i watched my water temp just immediately shoot to the red. pulled over and let it sit. end up the thermostat just magically failed me halfway through my journey in the middle of no where. after i got home i put in in boiling water (180 degree thermostat). wouldn't even budge. went and got a 160 thermostat, problem solved.
thermostat is easy to at least just check, take the elbow off, two bolts, bam. might as well just test it, you'll either find the problem or rule one thing out.
thermostat is easy to at least just check, take the elbow off, two bolts, bam. might as well just test it, you'll either find the problem or rule one thing out.
very well could be........but again doesn't explain the NO CIRCULATION issue........
hey OP.......alot of people think when a thermostat goes bad no water circulates..........and this is not the truth.......water will still circulate just at a very slow rate...........so if there is no water pressure from the crossover on the back of the head and no evidence of any coolant flow then its most likely the water pump........espically after i read this whole thread now I'm 99% its your pump.....
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Verdad Gallardo Mechanical waterpumps just don't up and give out w/out making a retched noise or some sort of tell tale sign. Because of its physical connection to the engine it virtually impossible for the pump to give out unless something snaps. What it reads like is the he reconnected the hose and there was not enough coolant to keep the pump primed.
dude if you were just driving along and the temp shot up like that the water pump probably stopped circulating water......upon that happening it will get really hot really fast usually in under 30 seconds.......pull the radiator cap off and start the car up if there is water squirting out of the little hose that connects right at the top of the radiator (under the cap) then the pump is workign......if not you are not circulating water.......this should be circulating even with the thermostat closed and the engine cold and running............I'm saying its the water pump that took a dump on you....
i originaly had a mechanical pump on my 355 that took a dump on me...........I didn't hear a damn thing and it did exactly this......just stopped working...........turns out the shaft broke off the impellor and spun inside of it and because of the coolant it stayed lubricated and just spun and I didn't hear anything.........that was when i went to electric....
yeah it was definitely my thermostat that went.. 
i've been driving it for 5-6 months daily since then with no issues what so ever.. haha
when you're climbing hills under boost it doesn't take long to heat up with little water circulation!
i've been driving it for 5-6 months daily since then with no issues what so ever.. hahawhen you're climbing hills under boost it doesn't take long to heat up with little water circulation!
Joe, that's 2x in the last month I've heard you disapprove of the nose-up bleed technique. You mentioned the last time "if bled properly..." How do you do it? Maybe there is a step a lot of us are missing, since a lot of folks find it tricky. For me the last 2 (and only) times, the cars just happened to be on ramps for an opti swap and bled them like any other car, bleeders open, never thought about it. Seemed too easy after hearing lots of people talking about what a pain it was. What's the secret? Or is that the secret- don't forget the bleeders, especially the one out of sight under the elbow?
Last edited by Gojira94; Mar 3, 2011 at 02:00 PM.
If the radiator is the lowest point the air definatly wound't be trapped there.......last time I checked air is lighter than water ......if there is any air in the system it gets forced up to the highest point which is at the top of the upper hose and near the thermostat.....hence the bleeder on the top of the water neck
......if there is any air in the system it gets forced up to the highest point which is at the top of the upper hose and near the thermostat.....hence the bleeder on the top of the water neck I tried bleeding mine using the bleeders... Never worked until I jacked up the nose but hey whatever works for you clearly works for you. By the time I could get air pockets out the cooling system would be steam locked and then It's just pointless. I was just offering advice since it bled in no time with the nose up for me when bleeders weren't enough.
I have also used a coolant system pressure tester to bleed the system if you don't want to wait for the coolant to normally pressurize.
The key thing is to keep the bleeders open while you fill the radiator. It's a breeze if this is done.
The key thing is to keep the bleeders open while you fill the radiator. It's a breeze if this is done.