Winter Preparation. Radiator flush and heater core back flush
Thread Starter
Member
Joined: Sep 2013
Posts: 124
Likes: 5
From: Etowah, North Carolina
Year: 1999
Model: Cherokee
Engine: Stright 6
Winter is coming preparation and I wanted to flush my radiator and back flush my heater core, what else would be a good idea to do to make it through the winter?
Anyone have a link to good videos showing how to complete the flush and back flush?
Anyone have a link to good videos showing how to complete the flush and back flush?
CF Veteran
Joined: Nov 2009
Posts: 8,172
Likes: 17
From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
How old r cooling system components? Money/time spent on the XJ cooling system can never be considered as money/time wasted.
Flush the heater core, motor and radiator separate from each other. U don't want crud from one clogging another. Disconnect the heater and top rad hoses from the stat cover. Disconnect the bottom rad hose from the water pump. Stick a garden hose in the heater hose and flush. Stick the garden hose in the heater hose nipple on the stat cover and flush. Stick the garden hose in the top rad hose and flush.
Flush the heater core, motor and radiator separate from each other. U don't want crud from one clogging another. Disconnect the heater and top rad hoses from the stat cover. Disconnect the bottom rad hose from the water pump. Stick a garden hose in the heater hose and flush. Stick the garden hose in the heater hose nipple on the stat cover and flush. Stick the garden hose in the top rad hose and flush.
Last edited by djb383; Oct 9, 2014 at 09:49 AM.
Thread Starter
Member
Joined: Sep 2013
Posts: 124
Likes: 5
From: Etowah, North Carolina
Year: 1999
Model: Cherokee
Engine: Stright 6
How old r cooling system components? Money/time spent on the XJ cooling system can never be considered as money/time waisted.
Flush the heater core, motor and radiator separate from each other. U don't want crud from one clogging another. Disconnect the heater and top rad hoses from the stat cover. Disconnect the bottom rad hose from the water pump. Stick a garden hose in the heater hose and flush. Stick the garden hose in the heater hose nipple on the stat cover and flush. Stick the garden hose in the top rad hose and flush.
Flush the heater core, motor and radiator separate from each other. U don't want crud from one clogging another. Disconnect the heater and top rad hoses from the stat cover. Disconnect the bottom rad hose from the water pump. Stick a garden hose in the heater hose and flush. Stick the garden hose in the heater hose nipple on the stat cover and flush. Stick the garden hose in the top rad hose and flush.
I have had the Jeep for about 18 months and have only changed the upper radiator hose. The previous owner used it as a third family car and he cared well for itand it shows.
I am planning on changing thermostat, both heater hoses, lower radiator hoseand coolant.
What am I missing?
CF Veteran
Joined: Sep 2011
Posts: 4,172
Likes: 4
From: Riviera, Texas
Year: 1998 Sport
Model: Cherokee
Engine: 4.0
I have had the Jeep for about 18 months and have only changed the upper radiator hose. The previous owner used it as a third family car and he cared well for itand it shows.
I am planning on changing thermostat, both heater hoses, lower radiator hoseand coolant.
What am I missing?
I am planning on changing thermostat, both heater hoses, lower radiator hoseand coolant.
What am I missing?
CF Veteran
Joined: Nov 2009
Posts: 8,172
Likes: 17
From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
I have had the Jeep for about 18 months and have only changed the upper radiator hose. The previous owner used it as a third family car and he cared well for itand it shows.
I am planning on changing thermostat, both heater hoses, lower radiator hoseand coolant.
What am I missing?
I am planning on changing thermostat, both heater hoses, lower radiator hoseand coolant.
What am I missing?
Unless u enjoy draining/refilling coolant, replace all the cooling system parts at once.The water pump, fan clutch and t-stat r super easy to replace when the old rad is out of the way. Install the new rad last. <$250 buys it all, including a new rad, and doing it on a Saturday afternoon when all the parts stores r open is preferable to doing repairs late at night on the side of the road.
The XJ cooling system is not to be taken lightly and money/time spent on the cooling system can never be considered money/time wasted. There's an echo in here.
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There's no way u can tell how "well cared for" it is inside the cooling system by looking at the outside. Unless the glove box has receipts in it showing a new radiator and water pump, presume they r both 15 years old and on borrowed time. The entire cooling system may be 15 years old......who knows?
Unless u enjoy draining/refilling coolant, replace all the cooling system parts at once.
The water pump, fan clutch and t-stat r super easy to replace when the old rad is out of the way. Install the new rad last. <$250 buys it all, including a new rad, and doing it on a Saturday afternoon when all the parts stores r open is preferable to doing repairs late at night on the side of the road.
The XJ cooling system is not to be taken lightly and money/time spent on the cooling system can never be considered money/time wasted. There's an echo in here.
Unless u enjoy draining/refilling coolant, replace all the cooling system parts at once.The water pump, fan clutch and t-stat r super easy to replace when the old rad is out of the way. Install the new rad last. <$250 buys it all, including a new rad, and doing it on a Saturday afternoon when all the parts stores r open is preferable to doing repairs late at night on the side of the road.
The XJ cooling system is not to be taken lightly and money/time spent on the cooling system can never be considered money/time wasted. There's an echo in here.

Opinions ?
Seasoned Member
Joined: Aug 2014
Posts: 486
Likes: 1
From: Lehigh Valley PA
Year: 1989
Model: Cherokee
Engine: 4.0 renix
Rockauto.
All day. Every day.
Get them magnets bro.
My fridge is almost filled with them.
If it's fluid, exhaust piping, or gasket - I get them at local shops.
I will also venture to junkyards for spare motors (starters and alternator type stuff) as well as body and interior related stuff.
All day. Every day.
Get them magnets bro.
My fridge is almost filled with them.
If it's fluid, exhaust piping, or gasket - I get them at local shops.
I will also venture to junkyards for spare motors (starters and alternator type stuff) as well as body and interior related stuff.
CF Veteran
Joined: Nov 2009
Posts: 8,172
Likes: 17
From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
I'd recommend your local auto parts stores.....AutoZone, NAPA, Advance, Oreiley, etc. Having a problem with a "mail order" cooling system part takes your XJ down for however long the mail/shipping takes.
Unless u like multiple drain/refills of coolant, do all the parts at the same time. Water pump, fan clutch and t-stat can almost be replaced blindfolded when the old rad is out of the way. The new rad goes in last.
Unless u like multiple drain/refills of coolant, do all the parts at the same time. Water pump, fan clutch and t-stat can almost be replaced blindfolded when the old rad is out of the way. The new rad goes in last.
Last edited by djb383; Oct 9, 2014 at 09:23 PM.
Well I drained and put new coolant in the system today at my buddy's place with his flush machine old coolant was gross gonna see how bad this turns. If it's nasty again soon I'm gonna do a full cleaning with new t stat rad and water pump fan clutch is functioning as it should so I will leave that
CF Veteran
Joined: Nov 2009
Posts: 8,172
Likes: 17
From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
How do u know the fan clutch is functioning as it should? Fan clutch performance degrades with time/miles. Do u know how old the fan clutch is? $35 gets a new one that will perform at 100% (for a while).
Last edited by djb383; Oct 11, 2014 at 07:58 PM.
Thread Starter
Member
Joined: Sep 2013
Posts: 124
Likes: 5
From: Etowah, North Carolina
Year: 1999
Model: Cherokee
Engine: Stright 6
Today I back flushed separately the heater core, radiator, and engine replacing the water pump, thermostat, heater and radiator hoses, and filled with new anti freeze, everything took about 4 hours.
The hardest part of the job was replacing the lower radiator hose to the water pump, expanding the clamp to max you still can not put it on the hose, slip hose on water pump and slide clamp over water pump nipple. Learnt to put clamp on pump nipple first, put hose on, and then slide clamp onto hose.
The thermostat I removed was a 180F, I had all ready bought my parts and bought a 195F, book says 195F, is there an advantage to 180F, perhaps in summer?
All is good and happy now but before summer is here I may swap out the fan clutch.
The hardest part of the job was replacing the lower radiator hose to the water pump, expanding the clamp to max you still can not put it on the hose, slip hose on water pump and slide clamp over water pump nipple. Learnt to put clamp on pump nipple first, put hose on, and then slide clamp onto hose.
The thermostat I removed was a 180F, I had all ready bought my parts and bought a 195F, book says 195F, is there an advantage to 180F, perhaps in summer?
All is good and happy now but before summer is here I may swap out the fan clutch.
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