Help!! Lt1 overheating
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Teching In
Joined: Mar 2009
Posts: 10
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From: Indiana
Help!! Lt1 overheating I have a 95 trans am lt1 6 speed car.
I'm having major issues. I bought the car and pulled the motor SMS rebuilt it to a 355. I have had over heating problems ever since i put it all back together. I still havnt been able to drive the car. It's killing me.
I have replaced the thermostat, switched radiator, attempted to flush out the air, water pump seems to be working fine. The low coolant light is on and the fans won't kick on. I know the fans are an issue but I'm thinking it is still an air pocket. But idk. I'm lost. What now. I've tried everything i can think of. Please help. It's my only car now and it's down. Thanks bunches.
I'm having major issues. I bought the car and pulled the motor SMS rebuilt it to a 355. I have had over heating problems ever since i put it all back together. I still havnt been able to drive the car. It's killing me.
I have replaced the thermostat, switched radiator, attempted to flush out the air, water pump seems to be working fine. The low coolant light is on and the fans won't kick on. I know the fans are an issue but I'm thinking it is still an air pocket. But idk. I'm lost. What now. I've tried everything i can think of. Please help. It's my only car now and it's down. Thanks bunches.
The fans should definitely come on...that's the problem, as far as air in the system, try parking it on a steep driveway and bleed the air (if there is any) from the bleeder fittings while the car warms up and radiator cap open....once water is flowing/boiling and the car heats up to operating temp that SHOULD get the air out. Get the fans checked out, sounds like an electrical issue.
How are u bleeding the air out? What did u do to get the fans to work? U could do ur basics . Therm, coolant sensor, and good coolant flush. I hope nothing was installed wrong. Wrong gaskets,engine not cleaned something clogged. To ur basics and start from there
You need to eliminate the air pocket issue before you do anything else; it's not that hard, you just need to be patient while it gets to operating temp and then just let it idle for 15 min or so until hot water is coming out the bleeder valves and keep topping of the coolant until it's overflowing....parking on a 45 degree angle makes this a piece of cake.
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You can either go this route or drain the radiator and block and start all over again w/ the bleeder screws open...
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Yea...45 degrees is a bit extreme; 30 degree hill or just jack up the front of your car does make it easier to get the air out than completely level ground. JMO as I've had to do this more times than I should...every ******* part of the coolant system on BOTH my F-body's has been replaced now
Don't even get me started on the power steering pump cooler issues I had on my Firehawk.
I've never run in to trouble doing this...in fact the LT1 owners "bible" clearly states: "Thou shalt Use a 50/50 mix of coolant to water, fill thou system through the radiator neck (thou bleeder valves shalt remain OPEN). Thou should hear a hiss of air from the bleeder valves as thou pours in the coolant...and it was good. Amen.http://shbox.com/1/4th_gen_tech2.html#radflush
LOL people should read "the bible" more http://shbox.com/page/index.html
95% of the maintenance questions asked here are right here...make a damn favorite everybody
95% of the maintenance questions asked here are right here...make a damn favorite everybody
Smoking the good stuff eh?
You just said: "Those who've run into this before do not open both bleeder screws while filling the cooling system which can cause all kinds of air pocket trouble. "
Then you completely contradicted your self with: "No air pocket problems will happen if the bleeder screws are left open while filling the radiator." (AFTER you read the shbox.com article on it)
So which is it?!.. open them or don't open them when you fill the radiator...LOL
You just said: "Those who've run into this before do not open both bleeder screws while filling the cooling system which can cause all kinds of air pocket trouble. "Then you completely contradicted your self with: "No air pocket problems will happen if the bleeder screws are left open while filling the radiator." (AFTER you read the shbox.com article on it)
So which is it?!.. open them or don't open them when you fill the radiator...LOL
Smoking the good stuff eh? You just said: "Those who've run into this before do not open both bleeder screws while filling the cooling system which can cause all kinds of air pocket trouble. "
Then you completely contradicted your self with: "No air pocket problems will happen if the bleeder screws are left open while filling the radiator." (AFTER you read the shbox.com article on it)
So which is it?!.. open them or don't open them when you fill the radiator...LOL
You just said: "Those who've run into this before do not open both bleeder screws while filling the cooling system which can cause all kinds of air pocket trouble. "Then you completely contradicted your self with: "No air pocket problems will happen if the bleeder screws are left open while filling the radiator." (AFTER you read the shbox.com article on it)
So which is it?!.. open them or don't open them when you fill the radiator...LOL
Comprehension fail.
I thought I made myself clear, however I should have completed that sentence. What I was saying is those who run into problems with air pockets do not open the bleeder screws before trying to fill cooling system. I figured by quoting Knickle89's sentence regarding his air pocket problem it made it clear. I guess I was wrong.
So far I have never opened any of the bleeder screws and I have no overheating problems. I'm afraid if I open one of the bleeder screws I never get it sealed again as the previous owner used a vice grip as a wonder tool. What I do is just let the engine warm up, remove the cap and add water as the engine cools and the level drops and do it again. After two cycles the reservoir does the rest. The "tuner" decided the fans should be on anytime the engine runs so that may be a factor.
(Was tempted to say, "When water runs out of the dipstick tube I quit!" Sorry, I'm twisted.
The other day I pulled the heater hose with the bleeder screw and there was coolant up there, so I guess it works. I'm running about 75% distilled water and 25% green Prestone. (Our track frowns on antifreeze spills or I would run 50/50.)
Al 95 Z28 Frankenstein w/optional mangled fasteners
(Was tempted to say, "When water runs out of the dipstick tube I quit!"
Sorry, I'm twisted. The other day I pulled the heater hose with the bleeder screw and there was coolant up there, so I guess it works. I'm running about 75% distilled water and 25% green Prestone. (Our track frowns on antifreeze spills or I would run 50/50.)
Al 95 Z28 Frankenstein w/optional mangled fasteners
However, every time I've ever had the radiator cap off while running the car, the damn thing just overflows out the neck.
If it's completely empty, I fill the block first through the T-stat opening in the top of the WP, then fill the radiator with both bleeders open. Close bleeders, put radiator cap on, start car, let it warm up, then open T-stat housing bleeder first, then do the heater hose bleeder. Shut the car off, and pull the radiator cap once it's cool. Top off the radiator, and run through a couple more heat cycles until it's full and no top-off is needed. Has worked like a charm for me 6+ times now.
did anybody pick up on the "my oil pressure dropped" statement??? kind of concerning to me.......
also im not sure who built the motor but how about the head gaskets.......builders cound easily get confused between a SBC and an LT1 gasket which will block off water passages and create an overheating problem............not saying this is the issue but it is possible
as for over heating and this whole air pocket deal.........i have never once had an issue bleeding any lt1 system........follow this procedure.....
with the car cold open the radiator cap and fill the radiator to the top with the bleeder screw open.......start the car and continue adding water untill you have a steady stream of water out of the bleeder screw........then hold the car at 1500-2000rpm and top off the radiator again......cap the radiator, close the bleeder and let the car back down to idle........
you don need to park on a hill, lift up the front of the car, do 13 jumping jacks and pat ur self on the head at the same time to get the system to run correctly........the internet loves to over complicate things.......
good luck!!
also im not sure who built the motor but how about the head gaskets.......builders cound easily get confused between a SBC and an LT1 gasket which will block off water passages and create an overheating problem............not saying this is the issue but it is possible
as for over heating and this whole air pocket deal.........i have never once had an issue bleeding any lt1 system........follow this procedure.....
with the car cold open the radiator cap and fill the radiator to the top with the bleeder screw open.......start the car and continue adding water untill you have a steady stream of water out of the bleeder screw........then hold the car at 1500-2000rpm and top off the radiator again......cap the radiator, close the bleeder and let the car back down to idle........
you don need to park on a hill, lift up the front of the car, do 13 jumping jacks and pat ur self on the head at the same time to get the system to run correctly........the internet loves to over complicate things.......
good luck!!
Al 95 Z28 w/frozen cooling system.....