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help replacing heater core in 85 f150

  • Thread starter Thread starter gingerbreadman
  • Start date Start date Sep 21, 2004

gingerbreadman

Only half-baked
Founding Member
Jan 17, 2002
5,358
0
0
Go ahead, call me cheaky
Sep 21, 2004
#1
  • Sep 21, 2004
  • #1
gotta love them $900 trucks


heres the symptoms:
1. strong coolant smell in the cab with the heat on
2. windows fog up with heat on and on defrost
3. coolant overflow level droping
4. feel coolant under the air vent box under the hood


My guess is leaking heater core.

Its an 85 f150 4x4 300 i6, the big plastic looking thingamajig with the heater core and fan motor has "high output" on it.... Does that mean its a high output heater or a high output engine???

it looks to me like it unbolts from inside the cab,

can someone whose done this or has any input speak up here...


-gbm-
 

Hack

15 Year Member
Mar 23, 2004
1,945
13
69
Minneapolis
Sep 21, 2004
#2
  • Sep 21, 2004
  • #2
I just did it on my '92 this weekend. It took me maybe a couple hours. The hardest part was getting at a couple of the six screws holding the plastic case together.

The glove box snapped right out, no fasteners. The hoses were easy to replace. It was a little difficult getting the core to come out from under the dash, so I just pulled harder.

I hope your repair goes well.
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Sep 21, 2004
#3
  • Sep 21, 2004
  • #3
You have 3 nuts and 2 screws under the cash holding the heater case in, you have to pull the temp cable off the case, and unplug the blower resistor and the case should come right out for you. 1/2 hour for me, 3 hrs with the GBM Curse after putting the fire out
 

gingerbreadman

Only half-baked
Founding Member
Jan 17, 2002
5,358
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0
Go ahead, call me cheaky
Oct 3, 2004
#4
  • Oct 3, 2004
  • #4
Well i got at it today,

It turned out the fitting for one of the heater hoses off the heater core came loose they are just soldered on so i attempted to re solder it ...


Well since my soldering gun wasnt powerfull enough i fired up the propane torch Can you guess where this is going Well i got the fitting soldered back on all pretty like but in the process not realizing it i melted all the solder holding the top cap on so as i did a little bucket full of water air test to see if my solder held i realized as the whole top bubbled away I managed to get the top soldered back on, im not sure how well its gonna hold but it seems ok so far....

trials and tribulations i guess :canflag:


-gbm-
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Oct 3, 2004
#5
  • Oct 3, 2004
  • #5
gingerbreadman said:
Well i got at it today,

It turned out the fitting for one of the heater hoses off the heater core came loose they are just soldered on so i attempted to re solder it ...


Well since my soldering gun wasnt powerfull enough i fired up the propane torch Can you guess where this is going Well i got the fitting soldered back on all pretty like but in the process not realizing it i melted all the solder holding the top cap on so as i did a little bucket full of water air test to see if my solder held i realized as the whole top bubbled away I managed to get the top soldered back on, im not sure how well its gonna hold but it seems ok so far....

trials and tribulations i guess :canflag:


-gbm-
Click to expand...

I'm guessing it's JUNK, shouldn't be using propane on a heater core. I use natural gas, much cooler and easier to control. The heater doesn't have tubes like a radiator, the flat fins are soldiered together and it os almost impossible to clean them properly after you've screwed them up.

Chances are it will hold until it warms up, then sh'll leak like a siv , You may want to buy that new heater now
 

gingerbreadman

Only half-baked
Founding Member
Jan 17, 2002
5,358
0
0
Go ahead, call me cheaky
Oct 3, 2004
#6
  • Oct 3, 2004
  • #6
WORTH said:
I'm guessing it's JUNK, shouldn't be using propane on a heater core. I use natural gas, much cooler and easier to control. The heater doesn't have tubes like a radiator, the flat fins are soldiered together and it os almost impossible to clean them properly after you've screwed them up.

Chances are it will hold until it warms up, then sh'll leak like a siv , You may want to buy that new heater now
Click to expand...



I also hooked the heater core up outside the air box and ran the truck to operating temp with it sitting on the air cleaner, i didnt see any leaks, i also went for a little drive last night and didnt smell any anti freez....

time will tell ill watch the fluid level, maybe ill get lucky..........for once


-gbm-
 

Hack

15 Year Member
Mar 23, 2004
1,945
13
69
Minneapolis
Oct 3, 2004
#7
  • Oct 3, 2004
  • #7
gingerbreadman said:
Well i got at it today,

It turned out the fitting for one of the heater hoses off the heater core came loose they are just soldered on so i attempted to re solder it ...


Well since my soldering gun wasnt powerfull enough i fired up the propane torch Can you guess where this is going Well i got the fitting soldered back on all pretty like but in the process not realizing it i melted all the solder holding the top cap on so as i did a little bucket full of water air test to see if my solder held i realized as the whole top bubbled away I managed to get the top soldered back on, im not sure how well its gonna hold but it seems ok so far....

trials and tribulations i guess :canflag:


-gbm-
Click to expand...
Wow! and I thought I was cheap.. To me $30 or so for a new one is a great deal.

Impressive patience though.
 

gingerbreadman

Only half-baked
Founding Member
Jan 17, 2002
5,358
0
0
Go ahead, call me cheaky
Oct 3, 2004
#8
  • Oct 3, 2004
  • #8
Hack said:
Wow! and I thought I was cheap.. To me $30 or so for a new one is a great deal.

Impressive patience though.
Click to expand...



Well its $40 up north :canflag: for a new one

and i was out just now for a good spin, i dont see any fluid leaking and i still cant smell any antifreez.

i think it may have worked, and ya it did take somne patients,

p.s. worth, i may have exagerated just a tad for stangnet purposes on how bad i screwed the top up



-gbm-
 

gingerbreadman

Only half-baked
Founding Member
Jan 17, 2002
5,358
0
0
Go ahead, call me cheaky
Oct 5, 2004
#9
  • Oct 5, 2004
  • #9
housten we have a problem

-fogged up windshield and the pleasant arroama of preston


I kinda thought it was too good to be true, guess it just took a few days


-gbm-
 
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