Non- LS1 issue plz help
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im not an artist but i did a rough sketch. the red by the heater core is the inlet where i hook up the hose, and it then pushes it through the rad and out the rad cap outlet spout i add.
basically when your back flushing the heater core you are separating the entire heater core system away from the rest of the cooling system. only the hoses directly connected to the heater core are used during the backflush. so disconnect the 2 hoses at the water pump that lead to the heater core.
spray water from a garden hose in one of the lines and watch the other line till its clear water comming out.
switch hoses and reverse the process untill it clear in both directions
reconnect hoses to water pump
fill cooling system
bleed completely!
block off or disconnect any other connections. if your drawing is correct, i may be reading it wrong but instead of 2 hoses at the water pump there is 1 water pump connection and 1 t-stat connection.
spray water from a garden hose in one of the lines and watch the other line till its clear water comming out.
switch hoses and reverse the process untill it clear in both directions
reconnect hoses to water pump
fill cooling system
bleed completely!
block off or disconnect any other connections. if your drawing is correct, i may be reading it wrong but instead of 2 hoses at the water pump there is 1 water pump connection and 1 t-stat connection.
Last edited by doublea87; Dec 6, 2010 at 09:41 PM. Reason: add-on
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basically when your back flushing the heater core you are separating the entire heater core system away from the rest of the cooling system. only the hoses directly connected to the heater core are used during the backflush. so disconnect the 2 hoses at the water pump that lead to the heater core.
spray water from a garden hose in one of the lines and watch the other line till its clear water comming out.
switch hoses and reverse the process untill it clear in both directions
reconnect hoses to water pump
fill cooling system
bleed completely!
block off or disconnect any other connections. if your drawing is correct, i may be reading it wrong but instead of 2 hoses at the water pump there is 1 water pump connection and 1 t-stat connection.
spray water from a garden hose in one of the lines and watch the other line till its clear water comming out.
switch hoses and reverse the process untill it clear in both directions
reconnect hoses to water pump
fill cooling system
bleed completely!
block off or disconnect any other connections. if your drawing is correct, i may be reading it wrong but instead of 2 hoses at the water pump there is 1 water pump connection and 1 t-stat connection.
well the rear defrost is a completely different problem, chances are a fuse
did you try flushing the heater core system seprate from the block and radiator?
one odd problem that i had on my old 3800 firebird after changing the coolant hoses was i didnt tighten them enough (changed to a screw style hose clamp) and leaked coolant very slightly, didnt notice it until i pressure tested the system.
if you got heat then you found the problem. now its just a matter of fixing the problem for good
did you try flushing the heater core system seprate from the block and radiator?
one odd problem that i had on my old 3800 firebird after changing the coolant hoses was i didnt tighten them enough (changed to a screw style hose clamp) and leaked coolant very slightly, didnt notice it until i pressure tested the system.
if you got heat then you found the problem. now its just a matter of fixing the problem for good
If one heater core hose is cold then its plugged. At operating temp on a vehicle that doesnt have a plugged core, both heater hoses will be HOT. As others have stated, flush JUST the heater core. Disconnect both hoses at core. Attach your flushing hoses to the heater core and connect your garden hose to one of them. Put the other one into a buket to catch the water. Flush for 1 minute. Then swap the garden hose to the other hose and flush again for 1 minute. The purpose of putting the end of other hose into bucket is to see what kind of gunk you are getting out. Once flushed, be sure to top off the system and bleed all air out with bleeder. If its still not hot enough, and one of the the heater hoses is still cold, it may be too far plugged and will need to be replaced.
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If one heater core hose is cold then its plugged. At operating temp on a vehicle that doesnt have a plugged core, both heater hoses will be HOT. As others have stated, flush JUST the heater core. Disconnect both hoses at core. Attach your flushing hoses to the heater core and connect your garden hose to one of them. Put the other one into a buket to catch the water. Flush for 1 minute. Then swap the garden hose to the other hose and flush again for 1 minute. The purpose of putting the end of other hose into bucket is to see what kind of gunk you are getting out. Once flushed, be sure to top off the system and bleed all air out with bleeder. If its still not hot enough, and one of the the heater hoses is still cold, it may be too far plugged and will need to be replaced.
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When at operating temp, what do the heater hoses feel like? If one is hot and one is cold then the heater core isnt doing its job OR you arent getting flow through the core.
Try this. With engine cold, remove radiator cap and add coolant till its full. Crack open bleeder(s) and close when coolant begins to come out. Top off again at radiator. Start engine and operate to normal operating temp. Let cool down and recheck coolant level.
Do you have any leaks?
Try this. With engine cold, remove radiator cap and add coolant till its full. Crack open bleeder(s) and close when coolant begins to come out. Top off again at radiator. Start engine and operate to normal operating temp. Let cool down and recheck coolant level.
Do you have any leaks?
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It is 100% topped off, and that is how i bled the system. i kept repeating until nothing but coolant came out of bleeder.
after doing the flush now both heater core hoses are hot, the heat no longer gets cold it stays the same, but it not as hot as it should be.
after doing the flush now both heater core hoses are hot, the heat no longer gets cold it stays the same, but it not as hot as it should be.
couple things you need to bleed system with the car off and prefferabley cold. then tighten the bleeder and start run with cap off until no more air pockets. this is the way i have always bleed any system. you may have to rev motor with cap off to push coolant thru the heater core.
to flush heater core take compressed air at the core and blow thru both sides and make sure there are no restrictions. but it sounds like you have already ruled out the core.
may be a dumb question but did you ever check to see if the t-stat is working. without the t stat working correctly it will take well over an hour for the coolant temp to get hot enough to create heat. most stats are 185 and coolant fans dont come on until 212. make sure that the coolant is at temp when checking this stuff.
if you have good flow thru the core, water pump is cycling coolant, and you aren't getting any air in the system. then the only other possibliliy i can think of is bad intake manifold gaskets or head gaskets. i really doubt it though as the head gaskets never go bad on those and the intakes normally leak externally. i would say you either have air or the t-stat is bad and stuck open.
to flush heater core take compressed air at the core and blow thru both sides and make sure there are no restrictions. but it sounds like you have already ruled out the core.
may be a dumb question but did you ever check to see if the t-stat is working. without the t stat working correctly it will take well over an hour for the coolant temp to get hot enough to create heat. most stats are 185 and coolant fans dont come on until 212. make sure that the coolant is at temp when checking this stuff.
if you have good flow thru the core, water pump is cycling coolant, and you aren't getting any air in the system. then the only other possibliliy i can think of is bad intake manifold gaskets or head gaskets. i really doubt it though as the head gaskets never go bad on those and the intakes normally leak externally. i would say you either have air or the t-stat is bad and stuck open.
What temp is the engine getting up to? Yes you will have to look at this with a scan tool or if possible the DIC may have that parameter when scrolling thru the options. If its getting up to 200 or so then its getting up to temp.
What are the temps of the heater core hoses? Have access to an infrared thermometer? Can you hold your hand on them for a long period of time with engine at operating temp without burning your hand? Is it setting any codes in the PCM such as a P0128? Are you sure the temp door in the HVAC case is operating throughout its full range?
What are the temps of the heater core hoses? Have access to an infrared thermometer? Can you hold your hand on them for a long period of time with engine at operating temp without burning your hand? Is it setting any codes in the PCM such as a P0128? Are you sure the temp door in the HVAC case is operating throughout its full range?
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What temp is the engine getting up to? Yes you will have to look at this with a scan tool or if possible the DIC may have that parameter when scrolling thru the options. If its getting up to 200 or so then its getting up to temp.
What are the temps of the heater core hoses? Have access to an infrared thermometer? Can you hold your hand on them for a long period of time with engine at operating temp without burning your hand? Is it setting any codes in the PCM such as a P0128? Are you sure the temp door in the HVAC case is operating throughout its full range?
What are the temps of the heater core hoses? Have access to an infrared thermometer? Can you hold your hand on them for a long period of time with engine at operating temp without burning your hand? Is it setting any codes in the PCM such as a P0128? Are you sure the temp door in the HVAC case is operating throughout its full range?
Thread Starter
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