Tip & How-To about Dodge Caravan

Unclog heater core, rather than replace it !!

When dealing with a clogged heater core causing poor or no heat situation, I've had good success doing it myself, for about $25-$30 . First thing to look at is if you can get to your heater hoses, as some may be a nightmare, others are easily accessible, but the closer you can get to the heater core, where the hoses go into the firewall, the better. Many will allow you to remove the heater hoses right at the firewall which is ideal.
With engine cool, I simply remove the heater hoses (after draining down the system and making sure I don't spill antifreeze on the ground where animals can get to it, which if ingested could more than likely kill them), and attach a drill pump, and hose to one of the heater core tubes, then get an extra piece of garden hose, and attach it to the other core tube, and cut it long enough to run it back into a pail, as a return line, to recover the cleaning solution. The hose on the suction side of the drill pump also goes in to the pail. Then add 1 or 2 jugs of CLR, (calcium, lime, rust remover) available at most hardware stores, into the pail as my cleaning solution. With pressure side hose from pump attached to heater core tube, and other hose(suction) from pump inside pail to draw liquid, as well as return hose from core in pail, start up the drill pump, which can be driven with electric, or cordless drill. I circulate it through for a while, then stop and let it sit in the core to work at the calcium etc inside the core for a few minutes, longer the better. After running it through a few times that way, I reverse the hoses at the core, and run it through again, like a reverse flush, and repeat as above, letting it sit in there for a while from time to time. I will normally do this when it isn't urgent that the vehicle be used soon, and if at all possible, I will let the CLR sit in the core overnight just to give it that extra time to break things down inside that core. Then next morning, I will run it through again, and reverse hoses again, run it some more, then I'm done. Remove all hoses, re-attach heater hoses to core, and start vehicle, re-fill cooling system, with heater turned on to remove air in system, and your done. I found this quite effective as well on vehicles that tend to blow cooler air when idling, but get warmer when RPM's are increased, just due to less restriction now in heater core, allowing coolant to flow through better at idle as well as higher RPM's. I've saved $100's if not $1000's of dollars this way, not to mention a lot of aggravation trying to change the heater core. Even if it doesn't get you back to the heat you were getting when vehicle was new, if money is tight, or your just trying to make the vehicle last a little longer before your ready to replace it, this will probably get you the heat you need to get you through until it's warmer outside. If you can't get to the hoses at the firewall location, try following them back toward engine to a location that may be easier to work from. There you would want to buy a couple of "Barbed" fittings (Joiners) the proper size to enable you to cut heater hoses, attach hoses from pump, then re-attach heater hoses together when done. Be sure to get good quality fittings, and re-check for leaks after/occasionally, to be sure. Be sure to check also, that there isn't some type of valve restriction or whatever in the hose between where your planning on cutting hose and the heater core where it's attached, that will not allow flow through, as well as out on return hose. Be sure to store or dispose of cleaning solution (CLR) in a safe place. It does have other cleaning abilities, as labeled on the jug, and a simple coffee filter in a funnel, to filter out the debris from core and poured back into jugs will allow you to re-use it elsewhere, but if you do, please remember it has been contaminated with antifreeze, and if re-used for cleaning or whatever, make sure it's not an application where it may be ingested by animals, or humans. Best bet for safety sake, is to dispose of it properly to avoid that risk. Good luck to all who try it, and please keep me/us informed of results.

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low heat in cab of truck but gets hot when i speed up the motor


You may want to take a look at this tip I wrote, likely applies to your situation.

f041a09.jpgWhen dealing with a clogged heater core causing poor or no heat situation, I've had good success doing it myself, for about $25-$30 . First thing to look at is if you can get to your heater hoses, as some may be a nightmare, others are easily accessible, but the closer you can get to the heater core, where the hoses go into the firewall, the better. Many will allow you to remove the heater hoses right at the firewall which is ideal.
With engine cool, I simply remove the heater hoses (after draining down the system and making sure I don't spill antifreeze on the ground where animals can get to it, which if ingested could more than likely kill them), and attach a drill pump, and hose to one of the heater core tubes, then get an extra piece of garden hose, and attach it to the other core tube, and cut it long enough to run it back into a pail, as a return line, to recover the cleaning solution. The hose on the suction side of the drill pump also goes in to the pail. Then add 1 or 2 jugs of CLR, (calcium, lime, rust remover) available at most hardware stores, into the pail as my cleaning solution. With pressure side hose from pump attached to heater core tube, and other hose(suction) from pump inside pail to draw liquid, as well as return hose from core in pail, start up the drill pump, which can be driven with electric, or cordless drill. I circulate it through for a while, then stop and let it sit in the core to work at the calcium etc inside the core for a few minutes, longer the better. After running it through a few times that way, I reverse the hoses at the core, and run it through again, like a reverse flush, and repeat as above, letting it sit in there for a while from time to time. I will normally do this when it isn't urgent that the vehicle be used soon, and if at all possible, I will let the CLR sit in the core overnight just to give it that extra time to break things down inside that core. Then next morning, I will run it through again, and reverse hoses again, run it some more, then I'm done. Remove all hoses, re-attach heater hoses to core, and start vehicle, re-fill cooling system, with heater turned on to remove air in system, and your done. I found this quite effective as well on vehicles that tend to blow cooler air when idling, but get warmer when RPM's are increased, just due to less restriction now in heater core, allowing coolant to flow through better at idle as well as higher RPM's. I've saved $100's if not $1000's of dollars this way, not to mention a lot of aggravation trying to change the heater core. Even if it doesn't get you back to the heat you were getting when vehicle was new, if money is tight, or your just trying to make the vehicle last a little longer before your ready to replace it, this will probably get you the heat you need to get you through until it's warmer outside. If you can't get to the hoses at the firewall location, try following them back toward engine to a location that may be easier to work from. There you would want to buy a couple of "Barbed" fittings (Joiners) the proper size to enable you to cut heater hoses, attach hoses from pump, then re-attach heater hoses together when done. Be sure to get good quality fittings, and re-check for leaks after/occasionally, to be sure. Be sure to check also, that there isn't some type of valve restriction or whatever in the hose between where your planning on cutting hose and the heater core where it's attached, that will not allow flow through, as well as out on return hose. Be sure to store or dispose of cleaning solution (CLR) in a safe place. It does have other cleaning abilities, as labeled on the jug, and a simple coffee filter in a funnel, to filter out the debris from core and poured back into jugs will allow you to re-use it elsewhere, but if you do, please remember it has been contaminated with antifreeze, and if re-used for cleaning or whatever, make sure it's not an application where it may be ingested by animals, or humans. Best bet for safety sake, is to dispose of it properly to avoid that risk. Good luck to all who try it, and please keep me/us informed of results.

Nov 27, 2010 | Dodge Ram 1500 Cars & Trucks

1 Answer

remove fuel tank from trooper


When dealing with a clogged heater core causing poor or no heat situation, I've had good success doing it myself, for about $25-$30 . First thing to look at is if you can get to your heater hoses, as some may be a nightmare, others are easily accessible, but the closer you can get to the heater core, where the hoses go into the firewall, the better. Many will allow you to remove the heater hoses right at the firewall which is ideal.
With engine cool, I simply remove the heater hoses (after draining down the system and making sure I don't spill antifreeze on the ground where animals can get to it, which if ingested could more than likely kill them), and attach a drill pump, and hose to one of the heater core tubes, then get an extra piece of garden hose, and attach it to the other core tube, and cut it long enough to run it back into a pail, as a return line, to recover the cleaning solution. The hose on the suction side of the drill pump also goes in to the pail. Then add 1 or 2 jugs of CLR, (calcium, lime, rust remover) available at most hardware stores, into the pail as my cleaning solution. With pressure side hose from pump attached to heater core tube, and other hose(suction) from pump inside pail to draw liquid, as well as return hose from core in pail, start up the drill pump, which can be driven with electric, or cordless drill. I circulate it through for a while, then stop and let it sit in the core to work at the calcium etc inside the core for a few minutes, longer the better. After running it through a few times that way, I reverse the hoses at the core, and run it through again, like a reverse flush, and repeat as above, letting it sit in there for a while from time to time. I will normally do this when it isn't urgent that the vehicle be used soon, and if at all possible, I will let the CLR sit in the core overnight just to give it that extra time to break things down inside that core. Then next morning, I will run it through again, and reverse hoses again, run it some more, then I'm done. Remove all hoses, re-attach heater hoses to core, and start vehicle, re-fill cooling system, with heater turned on to remove air in system, and your done. I found this quite effective as well on vehicles that tend to blow cooler air when idling, but get warmer when RPM's are increased, just due to less restriction now in heater core, allowing coolant to flow through better at idle as well as higher RPM's. I've saved $100's if not $1000's of dollars this way, not to mention a lot of aggravation trying to change the heater core. Even if it doesn't get you back to the heat you were getting when vehicle was new, if money is tight, or your just trying to make the vehicle last a little longer before your ready to replace it, this will probably get you the heat you need to get you through until it's warmer outside. If you can't get to the hoses at the firewall location, try following them back toward engine to a location that may be easier to work from. There you would want to buy a couple of "Barbed" fittings (Joiners) the proper size to enable you to cut heater hoses, attach hoses from pump, then re-attach heater hoses together when done. Be sure to get good quality fittings, and re-check for leaks after/occasionally, to be sure. Be sure to check also, that there isn't some type of valve restriction or whatever in the hose between where your planning on cutting hose and the heater core where it's attached, that will not allow flow through, as well as out on return hose. Be sure to store or dispose of cleaning solution (CLR) in a safe place. It does have other cleaning abilities, as labeled on the jug, and a simple coffee filter in a funnel, to filter out the debris from core and poured back into jugs will allow you to re-use it elsewhere, but if you do, please remember it has been contaminated with antifreeze, and if re-used for cleaning or whatever, make sure it's not an application where it may be ingested by animals, or humans. Best bet for safety sake, is to dispose of it properly to avoid that risk. Good luck to all who try it, and please keep me/us informed of results.

Apr 15, 2010 | 1996 Isuzu Trooper

1 Answer

no heat


Over heat is caused by poor circulation of coolant. This problem can be: 1- The thermostat is not opening ( bad) causing coolant stagnant. 2- Water pump is bad, not circulate coolant. 3- Radiator is clogging up. It is full but water can not going through small clogging up tubes inside to have heat dissipated through the fines.
Since you also have no heat then I think the bad coolant causing the heater core clogged up also, unless the heater valve has a problem not allowing cooling flowing through the bypass hose to the heater core. Correct all 3 things above then you should be OK. Good luck.

Dec 12, 2009 | 2005 Nissan Sentra

1 Answer

heater blows cold air for 20min then blows hot


There are a few things that can cause this problem. Reason #1 a low coolant level can cause the heater core to receive less coolant flow hence causing the heat to come less quickly. reason #2 sticky heater control valve, if this control valve is stuck closed coolant cant enter the heater core hense wont heat up the cabin, reason #3 clogged heater core, over time some heater cores will clog up even sometimes start to leak in cabin. All these are normal circumstances and should be checked. Good luck

Dec 07, 2009 | 1999 Chevrolet Silverado 1500

1 Answer

overheating


Generally when the heater isn't heating anything and putting out cold air the heater core is bad. I have never worked on a BMW before and have never heard of a heater core causeing overheating, but because they are linked, it maybe a clog in the core causing poor coolant circulation.

Nov 10, 2008 | 1997 BMW 328

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