Heater core question

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Xltsportfun

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So in the process of cleaning out all the leaves and what not from my hvac system i pulled the heater core out and when i went to dump what was in it all the fluid came out only one side and what little came out the other was full of rust flakes, would a clogged/restricted heater core cause overheating To some degree? I ask because i have a 3 row all aluminum radiator and 180 tstat, new water pump, all new lines, and 4 electric fans (1x16" 3x12") that kick on at 200 and off at 180 but still overheat climbing hills or pulling a small atv trailer, have a vdo temp gauge with the correct sensor. Its really intermittent, ive pulled several other vehicles with it no problem, but then out of the blue itll start overheating and once it starts to itll never come back down until i shut it down and wait for a few hours, any help on this would most definitely be appreciated
 

chrlsful

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4 me? a 3 row is less cooling than the ol guys due to SIZE of tube. Anyway...
I'm unclear on if U had this chrusty ol thing looped into the sys w/the new alu. If so that may have brought gunk into the water jacket in the engine, the alu radiator etc. If this is true have the h. core cleaned (boiled some call it) and serviced - brought up to speed. Meanwhile butt the heater hosed (continious flow w/o h. core there) and flush ur system...several times, 1 even in reverse if possible (up'n out r. cap neck area not just thru/out pet ****/other end. Properly despose of these fluids as they are hazerdous to wild life forms. When water flows clean - drain, put in 'new' h. core & corect amount of antifrez/boil:H2O ratio..HTH.
 

miesk5

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Yo XLT,
As Chris advised.

And by Ford;
"...
  • Engine Overheats
  • Damaged water thermostat.
  • Damaged water pump.
  • Cooling fan inoperative.
  • Plugged radiator.
PINPOINT TEST B: ENGINE OVERHEATS
B1 CHECK COOLANT LEVEL
  • NOTE: If engine is hot, allow engine to cool down before proceeding.


  • Remove radiator cap and check coolant level at radiator coolant recovery reservoir.
Is coolant level OK?
YesNo
GO to B2.REFILL as outlined. REFER to Cooling System, Draining, Filling and Bleeding in the Cleaning and Inspection portion of this section. GO to Pinpoint Test A.
B2 CHECK COOLANT CONDITION
  • Check coolant for contaminants such as rust or corrosion. Also, check for color discoloration.
Is coolant condition OK?
YesNo
GO to B3.FLUSH system. REFER to Cooling System Flush Procedure in the Cleaning and Inspection portion of this section. RETEST system.
B3 CHECK FOR AIRFLOW OBSTRUCTION
  • Visually inspect A/C condenser core and radiator for obstructions, such as leaves or bugs.
Is there any obstruction?
YesNo
REMOVE obstruction and CLEAN A/C condenser core and radiator in the Cleaning and Inspection portion of this section. RETEST system.GO to B4.
B4 CHECK WATER THERMOSTAT OPERATION
  • Allow engine to run for 10 minutes.
  • Feel the inlet and outlet heater water hose and the underside of the upper radiator hose.
Are the upper radiator hose and heater water hoses cold?
YesNo
REPLACE water thermostat. REFER to Thermostat, Water in the Removal and Installation portion of this section. RETEST system.LEAVE engine RUNNING. GO to B5.
B5 CHECK COOLING FAN
  • Check for proper cooling fan clutch operation. Perform Fan Clutch Test. Refer to Component Tests in this section.
Did cooling fan clutch operate OK?
YesNo
CHECK the following:
  • Rust or scale in radiator
  • Water pump shaft and impeller
  • Collapsed lower hose
REPLACE fan clutch. REFER to Cooling Fan Blade and Fan Clutch in the Removal and Installation portion of this section. RETEST system."
 

Skitter302

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I've got a 3 row champion in my Bco with a 190 stat and stock fan. I can run up a 5mile long 7% grade at 90mph with out any issues. I would look into your cooling fans to make sure they are pulling enough air.
 
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Xltsportfun

Xltsportfun

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Had the radiator tested, 2 big hole that the shop cant repair, also did a leak down test on the engine and found out 3 out of the 4 cylinders on the drivers side were pushing air into both the crankcase and water jacket, and leakage into the exhaust during all 4 strokes, so engine is coming out
 

Skitter302

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Bummer. Pull it, use upgraded parts, put it back in and enjoy.
 

GunnySutton

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Dont
So in the process of cleaning out all the leaves and what not from my hvac system i pulled the heater core out and when i went to dump what was in it all the fluid came out only one side and what little came out the other was full of rust flakes, would a clogged/restricted heater core cause overheating To some degree? I ask because i have a 3 row all aluminum radiator and 180 tstat, new water pump, all new lines, and 4 electric fans (1x16" 3x12") that kick on at 200 and off at 180 but still overheat climbing hills or pulling a small atv trailer, have a vdo temp gauge with the correct sensor. Its really intermittent, ive pulled several other vehicles with it no problem, but then out of the blue itll start overheating and once it starts to itll never come back down until i shut it down and wait for a few hours, any help on this would most definitely be appreciated
So in the process of cleaning out all the leaves and what not from my hvac system i pulled the heater core out and when i went to dump what was in it all the fluid came out only one side and what little came out the other was full of rust flakes, would a clogged/restricted heater core cause overheating To some degree? I ask because i have a 3 row all aluminum radiator and 180 tstat, new water pump, all new lines, and 4 electric fans (1x16" 3x12") that kick on at 200 and off at 180 but still overheat climbing hills or pulling a small atv trailer, have a vdo temp gauge with the correct sensor. Its really intermittent, ive pulled several other vehicles with it no problem, but then out of the blue itll start overheating and once it starts to itll never come back down until i shut it down and wait for a few hours, any help on this would most definitely be appreciated
My 90 with a 302 overheated ONCE. I already had a new heater core, therm and housing, hoses etc... I flushed everything and upgraded to heavy duty water pump AND heavy duty fan clutch. No more over heating.
 

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